---------------------------------------------------------- AeroElectric-List Digest Archive --- Total Messages Posted Sat 08/21/10: 26 ---------------------------------------------------------- Today's Message Index: ---------------------- 1. 04:34 AM - Re: Battery cables and Firewall Penetrations (Harley) 2. 07:05 AM - Re: Plane Power IR Alternator Implementation in Z-13/8 (Jared Yates) 3. 07:36 AM - New operations model for the AeroElectric Connection (Robert L. Nuckolls, III) 4. 07:36 AM - Re: Jasco Alternator and Panel Ground Questions (stearman456) 5. 08:51 AM - Re: Plane Power IR Alternator Implementation in Z-13/8 (Robert L. Nuckolls, III) 6. 08:56 AM - Re: New operations model for the AeroElectric Connection (Richard Girard) 7. 09:06 AM - Re: New operations model for the AeroElectric Connection (Roger) 8. 09:35 AM - Re: New operations model for the AeroElectric Connection (James Robinson) 9. 09:44 AM - Re: New operations model for the AeroElectric Connection (Robert L. Nuckolls, III) 10. 09:44 AM - Re: New operations model for the AeroElectric Connection (Robert L. Nuckolls, III) 11. 09:45 AM - Re: New operations model for the AeroElectric Connection (Robert L. Nuckolls, III) 12. 09:52 AM - New operations model for the AeroElectric Connection (Dave) 13. 11:28 AM - Re: Tray Connectors...A Bad Idea. (Robert L. Nuckolls, III) 14. 12:02 PM - Re: Tray Connectors...A Bad Idea. (Ralph & Maria Finch) 15. 12:36 PM - Re: Tray Connectors...A Bad Idea. (Bill Mauledriver Watson) 16. 01:59 PM - Tray Connectors...OOPS. (Robert L. Nuckolls, III) 17. 02:03 PM - Re: Tray Connectors...A Bad Idea. (BobsV35B@aol.com) 18. 02:11 PM - Lowrance Airmap GPS Updates (David & Elaine Lamphere) 19. 02:16 PM - Re: Tray Connectors...A Bad Idea. (Robert L. Nuckolls, III) 20. 02:55 PM - Aircraft radios of yesteryear (Robert L. Nuckolls, III) 21. 03:48 PM - Re: Aircraft radios of yesteryear (BobsV35B@aol.com) 22. 04:35 PM - Re: Aircraft radios of yesteryear (Bruce B. Bell) 23. 06:53 PM - Re: Vertex VXA700 information needed (rparigoris) 24. 07:44 PM - Re: New operations model for the AeroElectric Connection (MLWynn@aol.com) 25. 08:16 PM - Re: Re: Vertex VXA700 information needed (Richard Girard) 26. 10:17 PM - Re: Vertex VXA700 information needed (rparigoris) ________________________________ Message 1 _____________________________________ Time: 04:34:17 AM PST US From: Harley Subject: Re: AeroElectric-List: Battery cables and Firewall Penetrations Tim... (if I may interrupt here, Bob...) Those ACS fittings you are referring to, Tim, are designed to take grommets inside the holes (except the small one which already has a rubber backing) to prevent damage to the wire. From the description on the ACS page: /Both types of shield ... accommodate rubber grommets up to outside diameter. Actual hole size in 2 piece shields is slightly larger than indicated to prevent chafing cable...Use grommets that fit tightly around the cable or wire to insure a good seal./ Harley ----------------------------------------------------------------- On 8/21/2010 12:02 AM, Tim Andres wrote: > > These: > http://www.aircraftspruce.com/catalog/appages/firewallshields.php > > I like the idea of the 90 bend but have not seen anything close. > > Tim > > ----------------------------------------------------------------- > > *From:* owner-aeroelectric-list-server@matronics.com > [mailto:owner-aeroelectric-list-server@matronics.com] *On > Behalf Of *Robert L. Nuckolls, III > *Sent:* Friday, August 20, 2010 7:15 PM > *To:* aeroelectric-list@matronics.com > *Subject:* RE: AeroElectric-List: Battery cables and Firewall > Penetrations > > At 09:06 PM 8/20/2010, you wrote: > > Any idea where you can get such a fitting Bob? The ones I see > at ACS look like they would cut insulation. > Thanks, Tim > > > Which ACS catalog number are you looking at? > > Bob . . . > > * * > * * > ** > ** > ** > *http://www.matronics.com/Navigator?AeroElectric-List* > ** > ** > *http://forums.matronics.com* > ** > ** > *http://www.matronics.com/contribution* > * * > > Checked by AVG - www.avg.com > 11:35:00 > > * > > > * ________________________________ Message 2 _____________________________________ Time: 07:05:00 AM PST US Subject: Re: AeroElectric-List: Plane Power IR Alternator Implementation in Z-13/8 From: Jared Yates Bob, thanks for your help! Your answer clarifies many of my questions. I was surprised by your answer about the test. Did I understand correctly that there is never a time to intentionally turn off the primary alternator and battery for the purpose of testing the SD-8 and it's associated circuitry's ability to supply the Ebus? On Fri, Aug 20, 2010 at 3:02 PM, Robert L. Nuckolls, III < nuckolls.bob@aeroelectric.com> wrote: > nuckolls.bob@aeroelectric.com> > > > At 10:27 AM 8/20/2010, you wrote: > I'm thinking about using one of these as the belt driven alternator in > Z-13/8: > > http://www.plane-power.com/AL12-EI60.htm > > It's their experimental, internally regulated alternator that also comes > with built in crowbar over voltage protection. I'm not sure that I have a > full understanding of the OV protection and control issues of IR alternators > and how they pertain to this unit. > > I have 3 primary questions- one for the AEC and two for Plane Power, though > I welcome any insight about all three from the AEC readers. > > So first, is it correct to say that Z24, Z24A, and the associated text on > page Z-5 apply to IR alternators as they come off of the auto parts shelf, > and not really to this unit? > > Correct . . . The P-P devices are not off-the-shelf > automotive. > > > Based on their conceptual wiring picture here: > http://www.plane-power.com/images/AL12_EI60%20Installation.pdf > > Primary Question 1: How would I make the wiring connections in Z13/8 with > this unit? Should their field enable lead go to the 2-3 DC Power Master > Switch with the 5A crowbar in the same place as Z13/8 depicts it? Also, > what about that other optional alternator off lead (see 3 below)? > > I think I understand that the battery dump issue (described at > http://www.aeroelectric.com/articles/Adapting_IR_Alternators_to_Aircraft.pdf) > is a problem in Z13/8 because we would like to occasionally (preflight, > first flight of the day, etc?) turn the primary alternator and master off, > and turn the ebus alternate feed on to test those associated switching > systems. Is that correct? > > No. "Battery Dump" is defined as the sudden reduction > of heavy alternator loads wherein the major portion > of that load included battery recharge current and > it's the BATTERY that's being disconnected. There > are no operational procedures that call for such > a "test". Further, the way the Z-figures are drawn, > such a test could not be conducted for the battery > is always disconnected AFTER the alternator is shut down. > > > Primary Question 2: Will it do any physical damage to anything to turn off > the 2-3 DC Power Master Switch while the engine is running (assuming that I > need to)? > > It has been a legacy design goal for all TC aircraft > to configure the system such that an alternator (or > generator) may be turned on or off at any time under > any conditions without hazard to other components > in the system. An alternator that is controlled > by breaking the field lead without breaking the > b-lead MEETS this design goal. So, no . . . the P-P > alternator may be turned on or off at anytime without > concern for hazard to any compoent. > > > Primary Question 3: Does opening their Alternator Field Enable Switch fully > shut down the alternator field? > > > Yes > > If the crowbar protection circuit pops that 5A CB, I should hope that > opening that switch > > "switch"??? Do you mean "breaker"? Yes, opening that > breaker offers a quiet, orderly and benign disabling > of the alternator. > > . . . would completely shut down the alternator field too. If so, then > what does that other "optional alternator off" lead do? > > That's not a control, it's an indicator light which > has some limited ability to annunciate alternator failure > and has been used in cars for decades. However, active > notification of low voltage by an independent sensing > system is the legacy approach to watching for and > announcing alternator failure. > > > Would I need to hook it up at all, and/or would I need to still hook it up > with a switch in the line? Is there a failure mode in the other circuit > that would require me to turn off a switch in the second line to shut the > alternator off? > > You can drop the P-P product directly into any > of the z-figures by simply eliminating any illustrated > external regulators and/or crowbar ov protection > modules. > > I was going to call plane power to ask them a few of these questions but I > need to make sure that I know what to ask about. Thanks in advance. > > I've discussed Plane-Power design philosophy with > them at length. It's a certainty that their answers > will be along the same lines as that which I've offered > above. > > Bob . . . > > ________________________________ Message 3 _____________________________________ Time: 07:36:10 AM PST US From: "Robert L. Nuckolls, III" Subject: AeroElectric-List: New operations model for the AeroElectric Connection Last year we made the decision to make the 'Connection more utilitarian and accessible by offering electronic versions. This was not done without some considerations of risk. In the Internet age, a popular/useful file "released into the wild" may suddenly propagate with amazing speed. Such is the case with the AeroElectric Connection. The .pdf version has been picked up on a host of file-sharing services and now enjoys circulation numbers in the tens of thousands of copies. There's an obvious down-side. This means that the publication side of the AeroElectric Connection ceases to be as strong source of revenue. The up-side is that the simple-ideas and recipes for success described therein enjoy much wider circulation to the benefit of the OBAM aviation community as a whole. Coincidentally, I have just read a book called "The Future of a Radical Price - Free" wherein the author describes economic and marketing models that exploit giving certain value away in order to promote the exchange of other value. This business model has been operating on the Internet for years and continues to grow . . . which demonstrates its value. Consideration of his advice combined with previous events cited marks a milestone in my own experiences and prompts a new modus operandi for the AeroElectric Connection. Beginning immediately, the printed copy price of the 'Connection will drop to $23 postage paid (media mail) in the us. $30 overseas (priority mail). Buying the printed book will be more convenient and probably less expensive than printing 300+ pages on your own printer. The PDF file has been loaded to the website for download at no charge. The Revision 13 to the 'Connection will offer a complete update and re-formatting of the book. Most chapters including the Z-figures will make direct references to a range of products and services offered by the AeroElectric Connection. There are big plans for expanding our design, manufacturing and consulting services on behalf of the OBAM aviation community. We will probably bring Appendix C (catalog and source-book of products) back. Anyone who has recently purchased a book or CD at current prices who feels short changed by the price reduction is encouraged to drop us a line. Our warranty offers a guarantee of perceived value for the lifetime of any product. Drop us a note and we'll make it right with you. All of our dealers will be getting shipments of additional books equal to 1/2 their present inventory to adjust their return on investment for having purchased quantities of the book. Bob . . . ________________________________ Message 4 _____________________________________ Time: 07:36:10 AM PST US Subject: AeroElectric-List: Re: Jasco Alternator and Panel Ground Questions From: "stearman456" Thanks, Bob. Your book sure takes alot of the mystery out of the wiring process - I'm already on my second highlighter! Dan Read this topic online here: http://forums.matronics.com/viewtopic.php?p=309623#309623 ________________________________ Message 5 _____________________________________ Time: 08:51:22 AM PST US From: "Robert L. Nuckolls, III" Subject: Re: AeroElectric-List: Plane Power IR Alternator Implementation in Z-13/8 At 09:02 AM 8/21/2010, you wrote: >Bob, thanks for your help! Your answer clarifies many of my >questions. I was surprised by your answer about the test. Did I >understand correctly that there is never a time to intentionally >turn off the primary alternator and battery for the purpose of >testing the SD-8 and it's associated circuitry's ability to supply the Ebus? Sure, you can do that. BATTERY DUMP is dependent upon sequences of events. First you have to have a heavily loaded alternator (engine rpm high, discharged battery that is demanding and receiving most of the alternator's output). Then you unhook the battery while leaving the alternator on line. The effect is much like the tug of war game where one of the opposing sides suddenly releases their grip on the rope when the other side is concentrating on a max effort. There's no way that the other side can keep from falling on their butts. The folks who design regulators must strive for a magic compromise between stability (SLOW response) and and accuracy (HIGH gain). In engineering-speak this is often referred to as "damping ratio". See: http://www.aeroelectric.com/Pictures/Curves/damping_ratio.gif Here you see the time versus temperature plots for various servo-systems tailored to hold a mass at some constant temperature. Raising the temperature of a large mass takes a lot of watts. But the device controlling the heater has to be fitted with some anticipatory features. If you're pouting out kilojoules of heat into kilograms of mass, you'd better start throttling things back as the system approaches the desired temperature. You can slow things way down and have an "over damped" system that is free of oscillations and overshoot. On the other hand, a high gain/ fast response characteristic may bring the temperature to the set point faster and with more accuracy, but tendency to overshoot and "wiggle" about the set-point is greater. This system is said to be "under damped". Now, imagine a controller that is optimally damped (middle curve). Consider what happens if the heater is turned on but sometime along the temperature rise cycle, you suddenly reduce the mass being heated by say 90%. What's a poor controller to do? Now unable to detect the loss of mass, the probability for overshoot and oscillation is huge. The battery is electrical "mass" which your regulator expects to be in place all the time. Hence the design goal that calls for alternators not to be switched on/off without a battery being on line too. If you study what happens while sitting at the controls and flipping switches, there's no way you can produce that sudden reduction of "mass". Alternators are never switched on/off without a battery being tied to the bus. Hence the design goals are satisfied and risks to the system are reduced to insignificance. Bob . . . ________________________________ Message 6 _____________________________________ Time: 08:56:06 AM PST US Subject: Re: AeroElectric-List: New operations model for the AeroElectric Connection From: Richard Girard If you don't mind a suggestion. Look at the Rotax model for distributing its engine manuals. They are free, but they are locked. You cannot cut or copy text out of them. If you want to send some significant point to someone, you have to re-type it. I think it assures that the manuals will not be corrupted either by accident or malicious intent. Just a thought. Rick Girard On Sat, Aug 21, 2010 at 9:35 AM, Robert L. Nuckolls, III < nuckolls.bob@aeroelectric.com> wrote: > *Last year we made the decision to make the 'Connection more utilitarian > and accessible by > offering electronic versions. This was not done without some considerations > of risk. > > In the Internet age, a popular/useful file "released into the wild" may > suddenly propagate with > amazing speed. Such is the case with the AeroElectric Connection. The .pdf > version has been > picked up on a host of file-sharing services and now enjoys circulation > numbers in the tens of > thousands of copies. > > There's an obvious down-side. This means that the publication side of the > AeroElectric Connection ceases > to be as strong source of revenue. The up-side is that the simple-ideas and > recipes for success described > therein enjoy much wider circulation to the benefit of the OBAM aviation > community as a whole. > > Coincidentally, I have just read a book called "The Future of a Radical > Price - Free" wherein > the author describes economic and marketing models that exploit giving > certain value away in > order to promote the exchange of other value. This business model has been > operating on the > Internet for years and continues to grow . . . which demonstrates its > value. Consideration of his > advice combined with previous events cited marks a milestone in my own > experiences and > prompts a new modus operandi for the AeroElectric Connection. > > Beginning immediately, the printed copy price of the 'Connection will drop > to $23 postage > paid (media mail) in the us. $30 overseas (priority mail). Buying the > printed book will be > more convenient and probably less expensive than printing 300+ pages on > your own printer. > The PDF file has been loaded to the website for download at no charge. > > The Revision 13 to the 'Connection will offer a complete update and > re-formatting of the book. > Most chapters including the Z-figures will make direct references to a > range of products and services > offered by the AeroElectric Connection. There are big plans for expanding > our design, manufacturing > and consulting services on behalf of the OBAM aviation community. We will > probably bring Appendix C > (catalog and source-book of products) back. > > Anyone who has recently purchased a book or CD at current prices who feels > short changed by the > price reduction is encouraged to drop us a line. Our warranty offers a > guarantee of perceived > value for the lifetime of any product. Drop us a note and we'll make it > right with you. All of > our dealers will be getting shipments of additional books equal to 1/2 > their present inventory > to adjust their return on investment for having purchased quantities of the > book. > > > Bob . . . > * > > * > > * > > -- Zulu Delta Kolb Mk IIIC 582 Gray head 4.00 C gearbox 3 blade WD Thanks, Homer GBYM ________________________________ Message 7 _____________________________________ Time: 09:06:15 AM PST US From: "Roger" Subject: Re: AeroElectric-List: New operations model for the AeroElectric Connection Anyone who has recently purchased a book or CD at current prices who feels short changed by the price reduction is encouraged to drop us a line. Our warranty offers a guarantee of perceived value for the lifetime of any product. Drop us a note and we'll make it right with you Bob . . . As I recall, I paid $35 for my book, which is a $12 difference from todays price. I feel that I have gotten at least an order of magnitude more in value from this forum and the Aeroelectric website, so... lets call it even. What you do is much appreciated, hope you stay with us for a long time to come. Roger ________________________________ Message 8 _____________________________________ Time: 09:35:22 AM PST US From: James Robinson Subject: Re: AeroElectric-List: New operations model for the AeroElectric Connection Bob I just wanted to pass on my thanks for all you do for our community. I followed your diagrams and ideas on my Glasair and the electrical has been a non issue for the years I have been flying. Exactly what I wanted. The info and assistance I recieved was worth far more than the cost of your book. Thanks again Jim James Robinson Glasair lll N79R Spanish Fork UT U77 ________________________________ From: "Robert L. Nuckolls, III" Sent: Sat, August 21, 2010 8:35:25 AM Subject: AeroElectric-List: New operations model for the AeroElectric Connection Last year we made the decision to make the 'Connection more utilitarian and accessible by offering electronic versions. This was not done without some considerations of risk. In the Internet age, a popular/useful file "released into the wild" may suddenly propagate with amazing speed. Such is the case with the AeroElectric Connection. The .pdf version has been picked up on a host of file-sharing services and now enjoys circulation numbers in the tens of thousands of copies. There's an obvious down-side. This means that the publication side of the AeroElectric Connection ceases to be as strong source of revenue. The up-side is that the simple-ideas and recipes for success described therein enjoy much wider circulation to the benefit of the OBAM aviation community as a whole. Coincidentally, I have just read a book called "The Future of a Radical Price - Free" wherein the author describes economic and marketing models that exploit giving certain value away in order to promote the exchange of other value. This business model has been operating on the Internet for years and continues to grow . . . which demonstrates its value. Consideration of his advice combined with previous events cited marks a milestone in my own experiences and prompts a new modus operandi for the AeroElectric Connection. Beginning immediately, the printed copy price of the 'Connection will drop to $23 postage paid (media mail) in the us. $30 overseas (priority mail). Buying the printed book will be more convenient and probably less expensive than printing 300+ pages on your own printer. The PDF file has been loaded to the website for download at no charge. The Revision 13 to the 'Connection will offer a complete update and re-formatting of the book. Most chapters including the Z-figures will make direct references to a range of products and services offered by the AeroElectric Connection. There are big plans for expanding our design, manufacturing and consulting services on behalf of the OBAM aviation community. We will probably bring Appendix C (catalog and source-book of products) back. Anyone who has recently purchased a book or CD at current prices who feels short changed by the price reduction is encouraged to drop us a line. Our warranty offers a guarantee of perceived value for the lifetime of any product. Drop us a note and we'll make it right with you. All of our dealers will be getting shipments of additional books equal to 1/2 their present inventory to adjust their return on investment for having purchased quantities of the book. Bob . . . ________________________________ Message 9 _____________________________________ Time: 09:44:21 AM PST US From: "Robert L. Nuckolls, III" Subject: Re: AeroElectric-List: New operations model for the AeroElectric Connection At 10:55 AM 8/21/2010, you wrote: >If you don't mind a suggestion. Look at the Rotax model for >distributing its engine manuals. They are free, but they are locked. >You cannot cut or copy text out of them. If you want to send some >significant point to someone, you have to re-type it. I think it >assures that the manuals will not be corrupted either by accident >or malicious intent. Just a thought. Yeah, I'll be doing that. But by the next time a new revision hits the www, there will be uncountable opportunities for accidental or malicious adventure for what's already out there. Such is the risk of being an inhabitant of our planet! Interestingly enough, I had several experiences at OSH many years ago where somebody walked up to the booth with a binder that contained a 'Connection that was obviously copied. Many of the pages were not "square". I never bothered to inquire and it really didn't matter. Knowing the circumstances would not have altered the reality. Best thing was to move on and build good airplanes. Bob . . . ________________________________ Message 10 ____________________________________ Time: 09:44:40 AM PST US From: "Robert L. Nuckolls, III" Subject: Re: AeroElectric-List: New operations model for the AeroElectric Connection At 11:05 AM 8/21/2010, you wrote: >Anyone who has recently purchased a book or CD at current prices who >feels short changed by the >price reduction is encouraged to drop us a line. Our warranty offers >a guarantee of perceived >value for the lifetime of any product. Drop us a note and we'll make >it right with you > >Bob . . . > >As I recall, I paid $35 for my book, which is a $12 difference from >todays price. I feel that I have gotten at least an order of >magnitude more in value from this forum and the Aeroelectric >website, so... lets call it even. > >What you do is much appreciated, hope you stay with us for a long >time to come. Thank you my friend. That's the plan. Bob . . . ________________________________ Message 11 ____________________________________ Time: 09:45:55 AM PST US From: "Robert L. Nuckolls, III" Subject: Re: AeroElectric-List: New operations model for the AeroElectric Connection At 11:34 AM 8/21/2010, you wrote: >Bob >I just wanted to pass on my thanks for all you do for our >community. I followed your diagrams and ideas on my Glasair and the >electrical has been a non issue for the years I have been >flying. Exactly what I wanted. The info and assistance I recieved >was worth far more than the cost of your book. >Thanks again Thank YOU! I'm pleased that the work is useful. Bob . . . ________________________________ Message 12 ____________________________________ Time: 09:52:40 AM PST US From: "Dave" Subject: AeroElectric-List: New operations model for the AeroElectric Connection Bob, I purchased your book a few years back for 35 dollars. I am currently updated through rev 12 (I think). I appreciate what you do for the OBAM community so much that I will probably buy your new format and rev 13 book just to do my part in helping keep the revenue stream flowing. Thanks for everything Dave ________________________________ Message 13 ____________________________________ Time: 11:28:01 AM PST US From: "Robert L. Nuckolls, III" Subject: Re: AeroElectric-List: Tray Connectors...A Bad Idea. At 07:44 AM 8/18/2010, you wrote: > >I am sure the notion of sliding a piece of electronics into a tray >with the connector on the back has some informative design history, >but it is a horrible idea for aircraft (and even cars). In general >you should avoid it and replace the connector with a hanging one >where the connections aren't attached to two separately moving bodies. It's true that connectors at the rear of slide-in accessories mating with connectors on captive trays have extra-ordinary design requirements. And there were a few radios wherein the designers had to learn the weaknesses in the worst way - field experience. Many of the first radios for GA aircraft didn't even mount on the panel. Take this cute little feller . . . http://tinyurl.com/29sfmdd This radio was battery powered and not intended to be mounted solidly to the airplane. See the leather carrying handle? One sat it in the seat, plugged in an antenna, headphones and mic and voila! You had an airborne radio communications system. The antenna was in fact, a device adapted from a car radio installation. You talked on a VHF frequency determined by which crystal you plugged into the panel (see slots for two other frequencies) and listened for the ground facility to reply over the local radio range, LF beacon or marker transmitter. Not too many years after, folks began to find ways to mount these new fangled devices to the panel and it didn't take long to realize that it was MUCH easier to do installation and maintenance if the mounting tray and harness was captive to the airplane and the radio simply slides into the tray. Exemplar radios included this device. http://tinyurl.com/29hm578 You can see the head of the radio-to-tray jackscrew at the upper edge of the LF receiver bezel. http://tinyurl.com/2c5hu4w The other end of the jackscrew can be seen here along with the Cinch-Jones connectors that mated with connectors captive to the tray. These connectors are still in production. http://tinyurl.com/yhm37ow At the same time, other manufacturers elected not to participate in that adventure. As I recall, this radio's installation tray http://tinyurl.com/3xklhct did not capture the mating connectors. The maintenance person had to crawl under the panel to mate/de-mate harnesses with the radio. Even today, the installed size and wire-count of some radios . . . http://tinyurl.com/2u58jrb doesn't offer practical tray designs and their mating harness connectors are captive directly to the radio chassis. Aircraft radios did suffer a sort of "dark ages" when connectors intended to engage card- edge fingers were pressed into service on new designs. King radio (and others) built a LOT of devices that used this genre' of wire to board connector: Emacs! That accepted pins looking like this: Emacs! At Cessna in 1963 or so, we did an audio distribution board that mounted some relays and provided a sort of junction box for integrating a stack of radios into the single-engine product line. The card-edge connector was imply not designed to perform well in the aircraft environment. The in-house experiment only lasted a few years. Recall that good connection science calls for low surface area, high-pressure contact between pin and socket. The thin, gold-plated fingers of soft copper and the wide, low pressure springs in the pins simply did not rise to the task. Further, these connectors are probably the most fragile interconnect devices ever. They are entirely suited for SOME limited applications and are still made . . . but you won't (or at least shouldn't) find them in a product destined for use in an airplane. These connectors are not well contained. Dust laden with moisture, oils, and grit can accumulate over time. There's no wire support to keep harness wiggles from "working" the pins in their housings. I'd venture a guess that 90+ percent of my observations of "connector grief" with panel mounted radios in light aircraft have involved a variant of a card-edge-to-wire product. Having said that, I'm not sure I'd recommend a great migration to modifying any radio that's still in service utilizing this connector style. It would probably be useful to install new pins in all the holes. Clean the card edge fingers with a solvent wetted swab (resist any temptation to buff with ANY form of abrasive), that gold plating is VERY thin! Then provide bundle support for the wires close to where they exit the connector housing. Beyond this example of mis-applied technologies, I think the researcher will find that tray mounted harness connectors have enjoyed secure, happy and long lived associations with their radio mounted mates. The design has been widely practiced over the full range of avionics from the present day descendant of the Mitchell Airboy up to and including electro-whizzies in military and spacecraft. The magic happens when the connector pin-socket combinations are truly crafted to the task, harnesses don't hang from the pin's insulation grip, housings do a good job of shielding pins from the environmental crud, and finally, the radio is properly captive in the tray by proper tightening of the retaining hardware. By the way, if any of you are interested in a little museum trip down Avionics Lane, I'll invite you to look over the collection of pictures here: http://aeroelectric.com/Pictures/Radios/ Some of us grey beards have had the pleasure of cranking on a few of these very same knobs. My first flying lesson in a rudder-pedal fitted included a how-to session on one of these: http://tinyurl.com/3xklhct Bob . . . ________________________________ Message 14 ____________________________________ Time: 12:02:04 PM PST US From: "Ralph & Maria Finch" Subject: RE: AeroElectric-List: Tray Connectors...A Bad Idea. Bob-you are the man. Your knowledge and *understanding* of both electrical issues and their history of development is truly remarkable and seldom seen nowadays in any field. Old School of the best kind. A tip-of-the-hat from Ralph Finch Davis, California, USA RV-9A QB-SA ________________________________ Message 15 ____________________________________ Time: 12:36:22 PM PST US From: Bill Mauledriver Watson Subject: Re: AeroElectric-List: Tray Connectors...A Bad Idea. I knew when this was posted it would generate an interesting dialog but didn't expect an avionics history lesson. Great stuff! Thanks Bob and Eric. Robert L. Nuckolls, III wrote: > At 07:44 AM 8/18/2010, you wrote: >> >> >> I am sure the notion of sliding a piece of electronics into a tray >> with the connector on the back has some informative design history, >> but it is a horrible idea for aircraft (and even cars). In general >> you should avoid it and replace the connector with a hanging one >> where the connections aren't attached to two separately moving bodies. > > It's true that connectors at the rear of > slide-in accessories mating with connectors > on captive trays have extra-ordinary design > requirements. And there were a few radios > wherein the designers had to learn the > weaknesses in the worst way - field experience. > > Many of the first radios for GA aircraft didn't > even mount on the panel. Take this cute little > feller . . . > > * http://tinyurl.com/29sfmdd* > > This radio was battery powered and not intended > snippety snip ________________________________ Message 16 ____________________________________ Time: 01:59:03 PM PST US From: "Robert L. Nuckolls, III" Subject: AeroElectric-List: Tray Connectors...OOPS. Somehow the image for the card-edge-finger pin got replace by a second housing image. Here's the corrected piece. B . . . >I am sure the notion of sliding a piece of electronics into a tray >with the connector on the back has some informative design history, >but it is a horrible idea for aircraft (and even cars). In general >you should avoid it and replace the connector with a hanging one >where the connections aren't attached to two separately moving bodies. It's true that connectors at the rear of slide-in accessories mating with connectors on captive trays have extra-ordinary design requirements. And there were a few radios wherein the designers had to learn the weaknesses in the worst way - field experience. Many of the first radios for GA aircraft didn't even mount on the panel. Take this cute little feller . . . http://tinyurl.com/29sfmdd This radio was battery powered and not intended to be mounted solidly to the airplane. See the leather carrying handle? One sat it in the seat, plugged in an antenna, headphones and mic and voila! You had an airborne radio communications system. The antenna was in fact, a device adapted from a car radio installation. You talked on a VHF frequency determined by which crystal you plugged into the panel (see slots for two other frequencies) and listened for the ground facility to reply over the local radio range, LF beacon or marker transmitter. Not too many years after, folks began to find ways to mount these new fangled devices to the panel and it didn't take long to realize that it was MUCH easier to do installation and maintenance if the mounting tray and harness was captive to the airplane and the radio simply slides into the tray. Exemplar radios included this device. http://tinyurl.com/29hm578 You can see the head of the radio-to-tray jackscrew at the upper edge of the LF receiver bezel. http://tinyurl.com/2c5hu4w The other end of the jackscrew can be seen here along with the Cinch-Jones connectors that mated with connectors captive to the tray. These connectors are still in production. http://tinyurl.com/yhm37ow At the same time, other manufacturers elected not to participate in that adventure. As I recall, this radio's installation tray http://tinyurl.com/3xklhct did not capture the mating connectors. The maintenance person had to crawl under the panel to mate/de-mate harnesses with the radio. Even today, the installed size and wire-count of some radios . . . http://tinyurl.com/2u58jrb doesn't offer practical tray designs and their mating harness connectors are captive directly to the radio chassis. Aircraft radios did suffer a sort of "dark ages" when connectors intended to engage card- edge fingers were pressed into service on new designs. King radio (and others) built a LOT of devices that used this genre' of wire to board connector: [] That accepted pins looking like this: [] At Cessna in 1963 or so, we did an audio distribution board that mounted some relays and provided a sort of junction box for integrating a stack of radios into the single-engine product line. The card-edge connector was imply not designed to perform well in the aircraft environment. The in-house experiment only lasted a few years. Recall that good connection science calls for low surface area, high-pressure contact between pin and socket. The thin, gold-plated fingers of soft copper and the wide, low pressure springs in the pins simply did not rise to the task. Further, these connectors are probably the most fragile interconnect devices ever. They are entirely suited for SOME limited applications and are still made . . . but you won't (or at least shouldn't) find them in a product destined for use in an airplane. These connectors are not well contained. Dust laden with moisture, oils, and grit can accumulate over time. There's no wire support to keep harness wiggles from "working" the pins in their housings. I'd venture a guess that 90+ percent of my observations of "connector grief" with panel mounted radios in light aircraft have involved a variant of a card-edge-to-wire product. Having said that, I'm not sure I'd recommend a great migration to modifying any radio that's still in service utilizing this connector style. It would probably be useful to install new pins in all the holes. Clean the card edge fingers with a solvent wetted swab (resist any temptation to buff with ANY form of abrasive), that gold plating is VERY thin! Then provide bundle support for the wires close to where they exit the connector housing. Beyond this example of mis-applied technologies, I think the researcher will find that tray mounted harness connectors have enjoyed secure, happy and long lived associations with their radio mounted mates. The design has been widely practiced over the full range of avionics from the present day descendant of the Mitchell Airboy up to and including electro-whizzies in military and spacecraft. The magic happens when the connector pin-socket combinations are truly crafted to the task, harnesses don't hang from the pin's insulation grip, housings do a good job of shielding pins from the environmental crud, and finally, the radio is properly captive in the tray by proper tightening of the retaining hardware. By the way, if any of you are interested in a little museum trip down Avionics Lane, I'll invite you to look over the collection of pictures here: http://aeroelectric.com/Pictures/Radios/ Some of us grey beards have had the pleasure of cranking on a few of these very same knobs. My first flying lesson in a rudder-pedal fitted included a how-to session on one of these: http://tinyurl.com/3xklhct Bob . . . ________________________________ Message 17 ____________________________________ Time: 02:03:33 PM PST US From: BobsV35B@aol.com Subject: Re: AeroElectric-List: Tray Connectors...A Bad Idea. Good Afternoon 'Lectric Bob. And prior to that ultra modern Mitchel VHF set, we used Bill Lear's portable in a small suitcase which transmitted on 3105kc and allowed us to receive the "Beam" on low frequency. It even had a built in loop antenna. We could rotate the whole radio and get a bearing to or from the station. With a little judicious maneuvering, we could figure out whether the station was ahead or behind us in a as little as ten minutes or so. The biggest problem with it was finding a long wire antenna. With such an antenna, we could talk to a tower from as far as fifteen miles away. Great stuff. Happy Skies, Old Bob In a message dated 8/21/2010 1:29:29 P.M. Central Daylight Time, nuckolls.bob@aeroelectric.com writes: At 07:44 AM 8/18/2010, you wrote: --> AeroElectric-List message posted by: "Eric M. Jones" I am sure the notion of sliding a piece of electronics into a tray with the connector on the back has some informative design history, but it is a horrible idea for aircraft (and even cars). In general you should avoid it and replace the connector with a hanging one where the connections aren't attached to two separately moving bodies. It's true that connectors at the rear of slide-in accessories mating with connectors on captive trays have extra-ordinary design requirements. And there were a few radios wherein the designers had to learn the weaknesses in the worst way - field experience. Many of the first radios for GA aircraft didn't even mount on the panel. Take this cute little feller . . . _http://tinyurl.com/29sfmdd_ (http://tinyurl.com/29sfmdd) This radio was battery powered and not intended to be mounted solidly to the airplane. See the leather carrying handle? One sat it in the seat, plugged in an antenna, headphones and mic and voila! You had an airborne radio communications system. The antenna was in fact, a device adapted from a car radio installation. You talked on a VHF frequency determined by which crystal you plugged into the panel (see slots for two other frequencies) and listened for the ground facility to reply over the local radio range, LF beacon or marker transmitter. Not too many years after, folks began to find ways to mount these new fangled devices to the panel and it didn't take long to realize that it was MUCH easier to do installation and maintenance if the mounting tray and harness was captive to the airplane and the radio simply slides into the tray. Exemplar radios included this device. _http://tinyurl.com/29hm578_ (http://tinyurl.com/29hm578) You can see the head of the radio-to-tray jackscrew at the upper edge of the LF receiver bezel. _http://tinyurl.com/2c5hu4w_ (http://tinyurl.com/2c5hu4w) The other end of the jackscrew can be seen here along with the Cinch-Jones connectors that mated with connectors captive to the tray. These connectors are still in production. _http://tinyurl.com/yhm37ow_ (http://tinyurl.com/yhm37ow) At the same time, other manufacturers elected not to participate in that adventure. As I recall, this radio's installation tray _http://tinyurl.com/3xklhct_ (http://tinyurl.com/3xklhct) did not capture the mating connectors. The maintenance person had to crawl under the panel to mate/de-mate harnesses with the radio. Even today, the installed size and wire-count of some radios . . . _http://tinyurl.com/2u58jrb_ (http://tinyurl.com/2u58jrb) doesn't offer practical tray designs and their mating harness connectors are captive directly to the radio chassis. Aircraft radios did suffer a sort of "dark ages" when connectors intended to engage card- edge fingers were pressed into service on new designs. King radio (and others) built a LOT of devices that used this genre' of wire to board connector: That accepted pins looking like this: At Cessna in 1963 or so, we did an audio distribution board that mounted some relays and provided a sort of junction box for integrating a stack of radios into the single-engine product line. The card-edge connector was imply not designed to perform well in the aircraft environment. The in-house experiment only lasted a few years. Recall that good connection science calls for low surface area, high-pressure contact between pin and socket. The thin, gold-plated fingers of soft copper and the wide, low pressure springs in the pins simply did not rise to the task. Further, these connectors are probably the most fragile interconnect devices ever. They are entirely suited for SOME limited applications and are still made . . . but you won't (or at least shouldn't) find them in a product destined for use in an airplane. These connectors are not well contained. Dust laden with moisture, oils, and grit can accumulate over time. There's no wire support to keep harness wiggles from "working" the pins in their housings. I'd venture a guess that 90+ percent of my observations of "connector grief" with panel mounted radios in light aircraft have involved a variant of a card-edge-to-wire product. Having said that, I'm not sure I'd recommend a great migration to modifying any radio that's still in service utilizing this connector style. It would probably be useful to install new pins in all the holes. Clean the card edge fingers with a solvent wetted swab (resist any temptation to buff with ANY form of abrasive), that gold plating is VERY thin! Then provide bundle support for the wires close to where they exit the connector housing. Beyond this example of mis-applied technologies, I think the researcher will find that tray mounted harness connectors have enjoyed secure, happy and long lived associations with their radio mounted mates. The design has been widely practiced over the full range of avionics from the present day descendant of the Mitchell Airboy up to and including electro-whizzies in military and spacecraft. The magic happens when the connector pin-socket combinations are truly crafted to the task, harnesses don't hang from the pin's insulation grip, housings do a good job of shielding pins from the environmental crud, and finally, the radio is properly captive in the tray by proper tightening of the retaining hardware. By the way, if any of you are interested in a little museum trip down Avionics Lane, I'll invite you to look over the collection of pictures here: _http://aeroelectric.com/Pictures/Radios/ _ (http://aeroelectric.com/Pictures/Radios/) Some of us grey beards have had the pleasure of cranking on a few of these very same knobs. My first flying lesson in a rudder-pedal fitted included a how-to session on one of these: _http://tinyurl.com/3xklhct_ (http://tinyurl.com/3xklhct) Bob . . . ________________________________ Message 18 ____________________________________ Time: 02:11:41 PM PST US From: "David & Elaine Lamphere" Subject: AeroElectric-List: Lowrance Airmap GPS Updates I was asked to forward this information on in case you guys hadn't heard.... Please be advised - not only does Lowrance NOT make/sell any more Aviation GPS units, you cannot get a Jeppeson navdata update for them either! I just looked at the LEI site - no updates since April. I then sent a note to Jeppeson to see if they would supply any data updates for Lowrance units. Below is the query and dismal answer: ======== Subject: Data updates It appears that Lowrance no longer supplies the Jepp updates for their 1000 and 2000C GPS units. Will these updates be supplied by you for downloading? ======== Their response: Thank you for contacting us. We apologize for the long delay in responding to you Unfortunately, we have stopped all support on all Lowrance Units Lowrance has shut down there Aviation Group and we have no further word if they will continue! When they shut down, we stopped all Navdata Production for those units. I myself, have the Airmap 2000c and now it's a good paperweight! I'm forced to buy a Garmin Sorry Sir ======================= ________________________________ Message 19 ____________________________________ Time: 02:16:48 PM PST US From: "Robert L. Nuckolls, III" Subject: RE: AeroElectric-List: Tray Connectors...A Bad Idea. At 02:01 PM 8/21/2010, you wrote: > > >Bob-you are the man. Your knowledge and *understanding* of both electrical >issues and their history of development is truly remarkable and seldom seen >nowadays in any field. Old School of the best kind. Thank you Ralph. Unfortunately, it just may be 'old school'. Now that I'm "out in the wild" myself I'm observing what might just be a cultural shift in the reverence for history. Most folks exposures to the study of history involves the memorization of names, places, dates and events. I've benefited from the study of practical history. What recipes for success have been demonstrated in the past . . . and what can we glean from those stories for (1) not having to re-invent the wheel, (2) discovery of those timeless, simple-ideas that are equally applicable but perhaps in a different recipe? A sort of connect-the-dots exercise that improves upon one's situational awareness. To forsake an understanding the past leads to a sort of intellectual entropy. Even as the magnitude of activity increases, so does the quantity of smoke and steam. Smoke from by-products of combustion, steam as a manifestation of energy needed to convert water to vapor. Both byproducts representing value expended never to be recovered. Sharing of practical history amongst folks on this and similar lists goes a long way to the reduction of smoke and steam while maximizing the value of what happens in our workshops. It's my pleasure to exercise these talents but without the list, that exercise is at risk of becoming only more smoke and steam. I thank you all for being there. Bob . . . ________________________________ Message 20 ____________________________________ Time: 02:55:00 PM PST US From: "Robert L. Nuckolls, III" Subject: AeroElectric-List: Aircraft radios of yesteryear At 04:02 PM 8/21/2010, you wrote: >Good Afternoon 'Lectric Bob. > >And prior to that ultra modern Mitchel VHF set, we used Bill Lear's >portable in a small suitcase which transmitted on 3105kc and allowed >us to receive the "Beam" on low frequency. It even had a built in >loop antenna. We could rotate the whole radio and get a bearing to >or from the station. With a little judicious maneuvering, we could >figure out whether the station was ahead or behind us in a as little >as ten minutes or so. If you ever run across any pictures, literature or stories about that era, I'd be pleased to get links/sources. > >The biggest problem with it was finding a long wire antenna. With >such an antenna, we could talk to a tower from as far as fifteen >miles away. Great stuff. Yeah, I wrote and illustrated an Accessory Kit for Cessna to put a Sun H.F. transceiver . . . http://www.aeroelectric.com/Pictures/Radios/Sun_Air_2.jpg in the Military 185 (U17) aircraft at the Pawnee Plant. We had a fixed wire that ran from cabin top to vertical fin and then out to the right wing tip. Then a trailing wire in the tailcone. For folks interested in such things you can see the kit instructions at: http://www.aeroelectric.com/Reference_Docs/Misc_PDF/AK-U-17-3B.pdf I'd forgotten about a ground adjustable loading coil installation behind the baggage compartment for making the fixed wire match the various installed crystals. Of course, if one was flying in a situation that allowed use of the trailing wire, you could run it out and tune it by watching the panel mounted antenna ammeter. Pretty heady stuff for HF in a small airplane in 1968. Bob . . . ________________________________ Message 21 ____________________________________ Time: 03:48:55 PM PST US From: BobsV35B@aol.com Subject: Re: AeroElectric-List: Aircraft radios of yesteryear Good Evening 'Lectric Bob, You may have recalled that most of the early straight 35 Bonanzas came from the factory with an automatically extending and retracting trailing antenna. It extended at around 100 MPH and retracted at the same speed when slowing down. It can be seen on some of the advertising copy for the early machines. It had a small wind sock cone that mounted between the stabilators on a mast about six inches high. Next time you see a 1947 or 48 Bonanza take a look back there. Chances are you will see the remnants of the mast where it was sawed off after the trailing antenna was an abandoned. Unfortunately, an awful lot of them got ripped off by catching on an airport fence when folks made their approach just a bit too fast. The FCC did take away our 3105 frequency and designated 3023.5 in lieu thereof. Not sure just when that was but I think it was about 1948. Back when we were using 3105, the air carriers were using 6210. When we went to 3023.5 the frequency for air carriers was changed as well but I have forgotten what that frequency was. I will see what I can locate in some of my WWII text books. Happy Skies, Old Bob In a message dated 8/21/2010 4:55:53 P.M. Central Daylight Time, nuckolls.bob@aeroelectric.com writes: At 04:02 PM 8/21/2010, you wrote: Good Afternoon 'Lectric Bob. And prior to that ultra modern Mitchell VHF set, we used Bill Lear's portable in a small suitcase which transmitted on 3105kc and allowed us to receive the "Beam" on low frequency. It even had a built in loop antenna. We could rotate the whole radio and get a bearing to or from the station. With a little judicious maneuvering, we could figure out whether the station was ahead or behind us in a as little as ten minutes or so. If you ever run across any pictures, literature or stories about that era, I'd be pleased to get links/sources. The biggest problem with it was finding a long wire antenna. With such an antenna, we could talk to a tower from as far as fifteen miles away. Great stuff. Yeah, I wrote and illustrated an Accessory Kit for Cessna to put a Sun H.F. transceiver . . . _http://www.aeroelectric.com/Pictures/Radios/Sun_Air_2.jpg _ (http://www.aeroelectric.com/Pictures/Radios/Sun_Air_2.jpg) in the Military 185 (U17) aircraft at the Pawnee Plant. We had a fixed wire that ran from cabin top to vertical fin and then out to the right wing tip. Then a trailing wire in the tailcone. For folks interested in such things you can see the kit instructions at: _http://www.aeroelectric.com/Reference_Docs/Misc_PDF/AK-U-17-3B.pdf _ (http://www.aeroelectric.com/Reference_Docs/Misc_PDF/AK-U-17-3B.pdf) I'd forgotten about a ground adjustable loading coil installation behind the baggage compartment for making the fixed wire match the various installed crystals. Of course, if one was flying in a situation that allowed use of the trailing wire, you could run it out and tune it by watching the panel mounted antenna ammeter. Pretty heady stuff for HF in a small airplane in 1968. Bob . . . (http://www.matronics.com/Navigator?AeroElectric-List) (http://www.matronics.com/contribution) ________________________________ Message 22 ____________________________________ Time: 04:35:08 PM PST US From: "Bruce B. Bell" Subject: Re: AeroElectric-List: Aircraft radios of yesteryear My A-35 1949 Bonanza (D-1730) had one. Came out the factory door June 1948. ; From: BobsV35B@aol.com Sent: Saturday, August 21, 2010 5:47 PM Subject: Re: AeroElectric-List: Aircraft radios of yesteryear Good Evening 'Lectric Bob, You may have recalled that most of the early straight 35 Bonanzas came from the factory with an automatically extending and retracting trailing antenna. It extended at around 100 MPH and retracted at the same speed when slowing down. It can be seen on some of the advertising copy for the early machines. It had a small wind sock cone that mounted between the stabilators on a mast about six inches high. Next time you see a 1947 or 48 Bonanza take a look back there. Chances are you will see the remnants of the mast where it was sawed off after the trailing antenna was an abandoned. Unfortunately, an awful lot of them got ripped off by catching on an airport fence when folks made their approach just a bit too fast. The FCC did take away our 3105 frequency and designated 3023.5 in lieu thereof. Not sure just when that was but I think it was about 1948. Back when we were using 3105, the air carriers were using 6210. When we went to 3023.5 the frequency for air carriers was changed as well but I have forgotten what that frequency was. I will see what I can locate in some of my WWII text books. Happy Skies, Old Bob In a message dated 8/21/2010 4:55:53 P.M. Central Daylight Time, nuckolls.bob@aeroelectric.com writes: At 04:02 PM 8/21/2010, you wrote: Good Afternoon 'Lectric Bob. And prior to that ultra modern Mitchell VHF set, we used Bill Lear's portable in a small suitcase which transmitted on 3105kc and allowed us to receive the "Beam" on low frequency. It even had a built in loop antenna. We could rotate the whole radio and get a bearing to or from the station. With a little judicious maneuvering, we could figure out whether the station was ahead or behind us in a as little as ten minutes or so. If you ever run across any pictures, literature or stories about that era, I'd be pleased to get links/sources. The biggest problem with it was finding a long wire antenna. With such an antenna, we could talk to a tower from as far as fifteen miles away. Great stuff. Yeah, I wrote and illustrated an Accessory Kit for Cessna to put a Sun H.F. transceiver . . . http://www.aeroelectric.com/Pictures/Radios/Sun_Air_2.jpg in the Military 185 (U17) aircraft at the Pawnee Plant. We had a fixed wire that ran from cabin top to vertical fin and then out to the right wing tip. Then a trailing wire in the tailcone. For folks interested in such things you can see the kit instructions at: http://www.aeroelectric.com/Reference_Docs/Misc_PDF/AK-U-17-3B.pdf I'd forgotten about a ground adjustable loading coil installation behind the baggage compartment for making the fixed wire match the various installed crystals. Of course, if one was flying in a situation that allowed use of the trailing wire, you could run it out and tune it by watching the panel mounted antenna ammeter. Pretty heady stuff for HF in a small airplane in 1968. Bob . . . List href="http://www.matronics.com/Navigator?AeroElectric-List">http://www. matronics.com/Navigator?AeroElectric-List ms.matronics.com/">http://forums.matronics.com tp://www.matronics.com/contribution">http://www.matronics.com/contributio n ________________________________ Message 23 ____________________________________ Time: 06:53:46 PM PST US Subject: AeroElectric-List: Re: Vertex VXA700 information needed From: "rparigoris" Hi Vern We purchased an adapter cable and an external PTT switch when we purchased our VXA700. We ohmed out the harness and it indeed has two separate switches, one connects mic high when you push PTT, and the other switch grounds PTT high. I have a schematic for VXA 700 that Vertex support sent us, it does not include enough information to figure out why the harness would use two switches to do what they are doing. After several calls and finally cornered the support guy, he bowed out by saying Vertex doesn't make the harness and can't comment on it. He said the VXA 700 is not intended to be hooked up to an audio panel. I know that when we hook up the VXA 700 to our PMA4000 audio panel and use the harness I have with external PTT switch it works fine. I talked to PS Engineering and told him I wanted to use the mini DPDT relay as you can see on the right side near coin on second pic I posted to replicate two mechanical switches. I asked him if he thought it was OK to supply power to the coil of relay and have PMA4000 do the grounding when I push the PTT that is located on sticks and he thought that would be fine. Someone knows why my harness uses two separate switches to transmit. Vertex support does not know why. PS Engineering does not know why. I do not know why. I do know that the two switch arrangement works fine. My partner is an EE and thinks it best we replicate what we do know. His gut feeling is leaving mic connected all the time may not be a good thing to do. Perhaps someone could speculate why they may do this? Built into unit is a speaker and mic. Anyway there's our reasoning how and why we connected the four wire Vertex plug to our audio panel. You mention it may be a good idea to install a diode across the relay coil. We already finished harness and it would be a big effort to open up harness and get close to relay to install diode. You can see size of relay against a penny on the right side: http://www.europaowners.org/forums/gallery2.php?g2_itemId=81445&g2_imageViewsIndex=1 You can enlarge the pic to full size by selecting full size on top right of screen. The specifics are listed on schematic about the relay we are using. There is no mA draw of coil on information we have but it is not very much of a draw. Could get information off the data sheet. My question to you is what potential problem or problems could be caused by not using a diode across the coil of this mini relay? Do you think I should try harness as it is wired and if we experience a problem/s you describe, then install a diode? Or perhaps go half way between the two and install a diode about 6" away from the relay? BTW we are supplying power to the relay coil through a 324 wire that is about 20# long. I also have some snapjacks on hand if you think that a better choice. Ron Parigoris Read this topic online here: http://forums.matronics.com/viewtopic.php?p=309694#309694 ________________________________ Message 24 ____________________________________ Time: 07:44:26 PM PST US From: MLWynn@aol.com Subject: Re: AeroElectric-List: New operations model for the AeroElectric Connection Gee Bob, I would have to second that. Your book and this web site are worth a lot more than I paid for it. I would be more inclined to send a donation than ask for a refund. The service you render here has undoubtedly saved lives and airframes. I think that referencing back to B & C is a really reasonable idea. Regards, Michael Wynn RV 8 Finishing San Ramon, CA Do Not Archive In a message dated 8/21/2010 9:07:25 A.M. Pacific Daylight Time, mrspudandcompany@verizon.net writes: Anyone who has recently purchased a book or CD at current prices who feels short changed by the price reduction is encouraged to drop us a line. Our warranty offers a guarantee of perceived value for the lifetime of any product. Drop us a note and we'll make it right with you Bob . . . As I recall, I paid $35 for my book, which is a $12 difference from todays price. I feel that I have gotten at least an order of magnitude more in value from this forum and the Aeroelectric website, so... lets call it even. What you do is much appreciated, hope you stay with us for a long time to come. Roger (http://www.matronics.com/Navigator?AeroElectric-List) (http://www.matronics.com/contribution) ________________________________ Message 25 ____________________________________ Time: 08:16:02 PM PST US Subject: Re: AeroElectric-List: Re: Vertex VXA700 information needed From: Richard Girard Ron, I don't know why either, exactly, except that the PTT switch that Icom sold me for my A22 is set up the same way with two switches. Somewhere I got the idea is that one switch is NC and the other is NO. The NC is connected to the transmitter, the NO to the reciever. When the button is just sitting there doin' nothin', the transmitter is grounded and the receiver is open. Push the switch and the opposite happens the receiver is grounded out and the transmitter is open. The idea is to prevent the receiver and the transmitter from forming a feedback loop. Feel free to tell me I don't know what I'm talking about, there's a good chance I don't, but I seem to remember someone on this forum 'splainin' it that way somewhere in the distant past. Interesting that the VXA 220 uses a single switch in exactly the manner Bob described when I wrote in asking for help just this last May. Rick On Sat, Aug 21, 2010 at 8:52 PM, rparigoris wrote: > rparigor@suffolk.lib.ny.us> > > Hi Vern > > We purchased an adapter cable and an external PTT switch when we purchased > our VXA700. > > We ohmed out the harness and it indeed has two separate switches, one > connects mic high when you push PTT, and the other switch grounds PTT high. > > I have a schematic for VXA 700 that Vertex support sent us, it does not > include enough information to figure out why the harness would use two > switches to do what they are doing. > > After several calls and finally cornered the support guy, he bowed out by > saying Vertex doesn't make the harness and can't comment on it. He said the > VXA 700 is not intended to be hooked up to an audio panel. > > I know that when we hook up the VXA 700 to our PMA4000 audio panel and use > the harness I have with external PTT switch it works fine. > > I talked to PS Engineering and told him I wanted to use the mini DPDT relay > as you can see on the right side near coin on second pic I posted to > replicate two mechanical switches. I asked him if he thought it was OK to > supply power to the coil of relay and have PMA4000 do the grounding when I > push the PTT that is located on sticks and he thought that would be fine. > > Someone knows why my harness uses two separate switches to transmit. Vertex > support does not know why. PS Engineering does not know why. I do not know > why. > > I do know that the two switch arrangement works fine. My partner is an EE > and thinks it best we replicate what we do know. His gut feeling is leaving > mic connected all the time may not be a good thing to do. Perhaps someone > could speculate why they may do this? Built into unit is a speaker and mic. > > Anyway there's our reasoning how and why we connected the four wire Vertex > plug to our audio panel. > > You mention it may be a good idea to install a diode across the relay coil. > We already finished harness and it would be a big effort to open up harness > and get close to relay to install diode. > > You can see size of relay against a penny on the right side: > > http://www.europaowners.org/forums/gallery2.php?g2_itemId=81445&g2_imageViewsIndex=1 > > You can enlarge the pic to full size by selecting full size on top right of > screen. The specifics are listed on schematic about the relay we are using. > There is no mA draw of coil on information we have but it is not very much > of a draw. Could get information off the data sheet. > > My question to you is what potential problem or problems could be caused by > not using a diode across the coil of this mini relay? > > Do you think I should try harness as it is wired and if we experience a > problem/s you describe, then install a diode? > > Or perhaps go half way between the two and install a diode about 6" away > from the relay? BTW we are supplying power to the relay coil through a 324 > wire that is about 20# long. > > I also have some snapjacks on hand if you think that a better choice. > > Ron Parigoris > > > Read this topic online here: > > http://forums.matronics.com/viewtopic.php?p=309694#309694 > > -- Zulu Delta Kolb Mk IIIC 582 Gray head 4.00 C gearbox 3 blade WD Thanks, Homer GBYM It is not bigotry to be certain we are right; but it is bigotry to be unable to imagine how we might possibly have gone wrong. - G.K. Chesterton ________________________________ Message 26 ____________________________________ Time: 10:17:44 PM PST US Subject: AeroElectric-List: Re: Vertex VXA700 information needed From: "rparigoris" Hi Rick If your Icom has two switches and is making one connection and breaking another when you push the PTT, it is different than my Vertex that makes two connections. On my Vertex VXA700 when you push the PTT one switch connects the mic high to pin 3 (mic high), this is a normal opened switch. The other switch connects mic low to pin 2 (PTT high), this is a normal opened switch. Thus my single relay is a double pole relay that just makes two connections when the PTT is depressed. My double pole relay is doing exactly the same thing as pressing the premade harness PTT I have, when the PTT is depressed, two individual single pole switches make. Would you mind taking an ohm meter to your set up and report back if in fact one switch is making and one breaking? If it is in fact like my Vertex where both switches make, I will give Icom and pick their brains! Ron Parigoris Read this topic online here: http://forums.matronics.com/viewtopic.php?p=309709#309709 ------------------------------------------------------------------------------------- Other Matronics Email List Services ------------------------------------------------------------------------------------- Post A New Message aeroelectric-list@matronics.com UN/SUBSCRIBE http://www.matronics.com/subscription List FAQ http://www.matronics.com/FAQ/AeroElectric-List.htm Web Forum Interface To Lists http://forums.matronics.com Matronics List Wiki http://wiki.matronics.com Full Archive Search Engine http://www.matronics.com/search 7-Day List Browse http://www.matronics.com/browse/aeroelectric-list Browse Digests http://www.matronics.com/digest/aeroelectric-list Browse Other Lists http://www.matronics.com/browse Live Online Chat! http://www.matronics.com/chat Archive Downloading http://www.matronics.com/archives Photo Share http://www.matronics.com/photoshare Other Email Lists http://www.matronics.com/emaillists Contributions http://www.matronics.com/contribution ------------------------------------------------------------------------------------- These Email List Services are sponsored solely by Matronics and through the generous Contributions of its members.