AeroElectric-List Digest Archive

Thu 01/26/12


Total Messages Posted: 15



Today's Message Index:
----------------------
 
     1. 04:30 AM - Re: Larger D-Sub pins (Stuart Hutchison)
     2. 04:47 AM - Re: Re: Fuses instead of breakers (Robert L. Nuckolls, III)
     3. 06:36 AM - Re: Instrument Earth Bus cable size (Eric M. Jones)
     4. 07:01 AM - Re: Re: Fuses instead of breakers (Valovich, Paul)
     5. 07:56 AM - fuses, breakers, and hydraulic pumps (Glen Matejcek)
     6. 09:17 AM - Re: fuses, breakers, and hydraulic pumps (Robert L. Nuckolls, III)
     7. 09:28 AM - Re: Larger D-Sub pins (Robert L. Nuckolls, III)
     8. 09:54 AM - Re: Larger D-Sub pins (Bruce)
     9. 12:07 PM - Re: Fuses instead of breakers (bcondrey)
    10. 12:46 PM - Re: Fuses instead of breakers (Jeff Page)
    11. 12:57 PM - Re: Re: Fuses instead of breakers ()
    12. 03:44 PM - Re: Fuses instead of breakers (Ed Holyoke)
    13. 05:02 PM - Re: Re: Fuses instead of breakers (Robert L. Nuckolls, III)
    14. 05:21 PM - Re: Re: Fuses instead of breakers (Robert L. Nuckolls, III)
    15. 06:57 PM - Re: Larger D-Sub pins (Stuart Hutchison)
 
 
 


Message 1


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    Time: 04:30:22 AM PST US
    From: "Stuart Hutchison" <stuart@stuarthutchison.com.au>
    Subject: Larger D-Sub pins
    Thanks for your help everyone. The current-carrying capacity of the wires isn't a factor in my installation ... they're only carrying signals or minor currents off to relays. The Infinity grips have a mix of 17 different 22AWG and 20AWG wires each, but I have already terminated each of those wires at a 25-pin D-Sub connector. The two grip functions are wired in parallel for the most part, so my aim is to connect both FWD and AFT grips via a "Y" loom terminating at one 25 or 37-pin D-Sub connector to mate with a main central loom. The "Y" loom will be fabricated entirely of 22AWG wires (disgregard the AWG ratings in my pic), but I thought it would be more convenient to use 18AWG pins where the wires come together at the top connector, rather than trim or fold away strands so that 2 x 22AWG wires fit into 20AWG pins. As Bob said, 2 x 22AWG wire insulation won't fit in the connector and makes pin removal difficult, so I thought it would also be more convenient to use 18AWG pins for this reason (but I haven't tried removing them). I found 18AWG pins at this site (bottom of the page), but they're asking $2 each ... http://www.aircraftelectronicssupply.com/garmin_install_supp.htm Cheers, Stu -----Original Message----- From: owner-aeroelectric-list-server@matronics.com [mailto:owner-aeroelectric-list-server@matronics.com] On Behalf Of Robert L. Nuckolls, III Sent: Thursday, January 26, 2012 4:26 AM Subject: RE: AeroElectric-List: Larger D-Sub pins --> <nuckolls.bob@aeroelectric.com> At 10:31 AM 1/25/2012, you wrote: >--> <stein@steinair.com> > >Most every shop has extras laying around because they almost never use >all of them supplied. Gimme a call if you need a few. > >BTW, unless the runs are long an AWG20 wire will work fine in place of >an AWG18. You beat me to it my friend. I will also suggest that it's perfectly okay to peel a few strands out of the "too large" wire to get them all into the 20AWG crimp cup of a standard pin. You'll have to leave the bare strands exposed over a greater length because the insulation will not go down into the wire opening of the connector. Experiment with an extra pin and a chunk of wire to establish the new strip dimensions. When somebody calls for putting overweight wires into a d-sub connector, the design goal is to REDUCE WIRE PATHWAY IMPEDANCE. Putting the larger wire into the pin does not increase the pin's current handling ability. Hence my suggestion for peeling out extraneous strands is not a technically 'evil' thing to do in terms of the physics. It would have an immeasurable impact on design goals that called for the larger wire. I think this is preferable to the FAT pin. It adds no bulk to wiring immediately behind the connector and leaves less exposed conductor. However, pulling this trick in an ISO/FAA/PP driven TC aircraft shop would probably get you fired or at least a 'ding' in your employment record. Bob . . .


    Message 2


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    Time: 04:47:21 AM PST US
    From: "Robert L. Nuckolls, III" <nuckolls.bob@aeroelectric.com>
    Subject: Re: Fuses instead of breakers
    At 09:47 PM 1/25/2012, you wrote: Bob, please do. In the meantime, for those of us just getting to wiring, would this be reasonable, or overkill? P.S. to previous post. I too would like to see an ignition system power from the battery bus. NOT for reasons of noise but for reasons of risk mitigation. When I have smoke in the cockpit, I'd like to KILL the entire electrical system without causing the engine to stop. This is why I've advocated that ANY electrically dependent engine get power directly from battery busses. This philosophy is illustrated in the Z-figures. Bob . . .


    Message 3


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    Time: 06:36:47 AM PST US
    Subject: Re: Instrument Earth Bus cable size
    From: "Eric M. Jones" <emjones@charter.net>
    (partial repost) I sell lots of Copper-Clad Aluminum cable to 300 mph fuel dragster and racecar builders, and weird groups doing strange things where the weight is important. I even sell the stuff to the companies building remote-controlled drones. Predator drones and the more advance secret stuff... Airbus and Boeing use similar CCA configurations, and they won't sell you any. I sell Super-2-CCA, Super-4-CCA, AWG-6-CCA (same dimensions as AWG-6 but CCA with Tefzel insulation), and Super-CCA RG+142 See my website. CCA is 60% the weight of copper for the same conductivity. If you have the battery on the firewall, you are okay. Otherwise, use CCA. Also see Bob's most excellent article, http://www.aeroelectric.com/articles/economics_of_weight_reduction.html and on my website: http://www.periheliondesign.com/fatwires_files/Coppercables.pdf -------- Eric M. Jones www.PerihelionDesign.com 113 Brentwood Drive Southbridge, MA 01550 (508) 764-2072 emjones@charter.net Read this topic online here: http://forums.matronics.com/viewtopic.php?p=364872#364872


    Message 4


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    Time: 07:01:20 AM PST US
    From: "Valovich, Paul" <pvalovich@dcscorp.com>
    Subject: Re: Fuses instead of breakers
    I built my RV-8A referencing Z13/8: forward mounted battery, one LSI, one m ag. Three fuze blocks in fwd baggage compartment inaccessible in flight. Th ree panel mounted CBs - Alt Field, Aux Alt Field and LSI. I do not feel that a fuze-blowing event for most circuits would benefit fro m restable CBs - something caused the initial overvoltage and chances that the fix is a reset CB are very slim. Design redundant systems, include inte rnal avionics batteries where it makes sense, execute proper failure proced ures, land as soon as practicable - or as soon as possible - and sort it ou t on the ground. For the normal and backup alternators - and LSI - I felt that there was ben efit from a reset capability. Nuisance trips, one time spikes, intermittent short, etc. I just might need the few minutes (perhaps) between trigger ev ents to land. 140 hours of trouble-free electrons so far. Paul Valovich N192NM


    Message 5


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    Time: 07:56:43 AM PST US
    From: Glen Matejcek <aerobubba@earthlink.net>
    Subject: fuses, breakers, and hydraulic pumps
    Hi Jeff- With regard to: >How about another example ? The popular approach is to use a pullable >breaker for the hydralic pump for the amphibious landing gear. If I >use a switch and a fuse, what size fuse ? I appreciate that I can >always install a bigger fuse if nuisance pops occur, ..... ......Are there any other reasons why a pullable circuit breaker would be >preferred for this situation ? There are two seperate potential issues here. First, is there an alternate source of hydraulic pressure? If you have a practical hand pump available, then the nuisance trip issue is just that. If the electric pump is your only practical source of hydraulic power, then things are a little different. I could envision a scenario where the motor for the hydraulic pump has degraded such that the current draw trips the circuit protection, leaving you with a gear up landing, or potentially worse, a partial gear landing. Personally, I would prefer resettable circuit protection in that scenario. FYI, YMMV, ETC, ETC Glen Matejcek


    Message 6


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    Time: 09:17:28 AM PST US
    From: "Robert L. Nuckolls, III" <nuckolls.bob@aeroelectric.com>
    Subject: Re: fuses, breakers, and hydraulic pumps
    There are two separate potential issues here. First, is there an alternate source of hydraulic pressure? If you have a practical hand pump available, then the nuisance trip issue is just that. If the electric pump is your only practical source of hydraulic power, then things are a little different. I could envision a scenario where the motor for the hydraulic pump has degraded such that the current draw trips the circuit protection, leaving you with a gear up landing, or potentially worse, a partial gear landing. Personally, I would prefer resettable circuit protection in that scenario. Cogent thoughts my friend. In spite of the fact that a Beech Sierra was a pig with wings, I appreciated the fact that the standby-gear extension system was a simple valve on the floor that allowed gear-up pressure to be relieved allowing the wheels to fall free. Personally, I would prefer resettable circuit protection in that scenario. I would offer the notion that if power to the motor is sufficiently robust (current limiter style protection) then a nuisance trip is entirely out of the picture. Any time you open a current limiter, something is REALLY BAD WRONG and being able to "give 'er one more try" is an incalculable long shot. Bob . . .


    Message 7


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    Time: 09:28:01 AM PST US
    From: "Robert L. Nuckolls, III" <nuckolls.bob@aeroelectric.com>
    Subject: Larger D-Sub pins
    At 06:24 AM 1/26/2012, you wrote: >Thanks for your help everyone. > >I thought it would also be more convenient to use 18AWG pins for this >reason (but I haven't tried removing them). Hmmm . . . hadn't thought about that. I'm not sure they CAN be removed with the legacy extraction tools. Given the complexity of your stick grip wiring I think I would give serious thought to building an etched circuit board for the relay-deck and stick-grip-junction- box. Your mating connectors then solder to the board. The board can mount the relays and perhaps a speed adjustment system. the mating connectors get 'really clean' with respect to materials and techniques. Express PCB has free software and really reasonable prices on double-sided, plated-thru boards laid up and ordered via your computer. Emacs! Bob . . .


    Message 8


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    Time: 09:54:52 AM PST US
    From: "Bruce" <BGray@glasair.org>
    Subject: Larger D-Sub pins
    Stu, On a personal preference note, it's generally not a good idea to put any function on a control stick that, if inadvertently activated, would in danger the aircraft. In your particular application, I would put engine start and flaps in that category. Bruce WWW.Glasair.org -----Original Message----- From: owner-aeroelectric-list-server@matronics.com [mailto:owner-aeroelectric-list-server@matronics.com] On Behalf Of Stuart Hutchison Sent: Thursday, January 26, 2012 7:24 AM Subject: RE: AeroElectric-List: Larger D-Sub pins Thanks for your help everyone. The current-carrying capacity of the wires isn't a factor in my installation ... they're only carrying signals or minor currents off to relays. The Infinity grips have a mix of 17 different 22AWG and 20AWG wires each, but I have already terminated each of those wires at a 25-pin D-Sub connector. The two grip functions are wired in parallel for the most part, so my aim is to connect both FWD and AFT grips via a "Y" loom terminating at one 25 or 37-pin D-Sub connector to mate with a main central loom. The "Y" loom will be fabricated entirely of 22AWG wires (disgregard the AWG ratings in my pic), but I thought it would be more convenient to use 18AWG pins where the wires come together at the top connector, rather than trim or fold away strands so that 2 x 22AWG wires fit into 20AWG pins. As Bob said, 2 x 22AWG wire insulation won't fit in the connector and makes pin removal difficult, so I thought it would also be more convenient to use 18AWG pins for this reason (but I haven't tried removing them). I found 18AWG pins at this site (bottom of the page), but they're asking $2 each ... http://www.aircraftelectronicssupply.com/garmin_install_supp.htm Cheers, Stu


    Message 9


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    Time: 12:07:07 PM PST US
    Subject: Re: Fuses instead of breakers
    From: "bcondrey" <bob.condrey@baesystems.com>
    FWIW, this subject has been discussed before on the AeroElectric list. Use the search function for the words "Klaus" and "crowbar" and you'll find a couple threads from early 2009. Turns out that it's not just over-voltage events that will cause them to crowbar but apparently over-temp. This was posted on Feb 1, 2009: "I have had to do one inflight reset on the Plasma III on one system once. The reset was successful and power was restored to the unit. I removed the unit and sent it back to Klaus for inspection. The fault was determined to be an overheat situation. That unit was located in an area without any real ventilation and without an form of cooling while operation in Arizona during the summer. the compartment temp was estimated to have exceeded 200 deg. F. The unit was modified to the latest version (lower heat output components and a ventilation port. The aircraft was modified to provide air circulation in that compartment. After 300+ hours on that unit no faults noted. The point, when the unit faulted it tripped the CB and was then reset and provided service throughout the remainder of that flight. " Without getting into the discussion of whether the design should or shouldn't be modified, my purpose on posting (now and back in early 2009) is simply to make those with dual LSE ignition setups aware that fuses can't be arbitrarily substituted for CBs in this case. Bob C Read this topic online here: http://forums.matronics.com/viewtopic.php?p=364895#364895


    Message 10


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    Time: 12:46:40 PM PST US
    From: Jeff Page <jpx@qenesis.com>
    Subject: Re: Fuses instead of breakers
    At 04:27 PM 1/25/2012, you wrote: > The reference to the FARs regarding battery bus circuits was useful. > My design doesn't exceed those specifications. Fortunately, with an > amateur-built aircraft, no bureaucrat can claim that a 5A circuit > protective device would be the size of both the fuse and the circuit > breaker. > Who said anything about regulations? Just because it's > in a holy-watered book doesn't mean it's not a > valuable ingredient in a recipe for success. I merely meant that a 5A fuse and a 5A breaker behave differently, but since the protection type is not specified, the rule could be interpreted as a maximum of a 5A fuse. > Are there any other reasons why a pullable circuit breaker would be > preferred for this situation ? > What controls the pump motor . . . a contactor? > Is it tailored for intermittent duty, hi-inrush > service like a starter-contactor? Sticking of this > device might pose an in-flight concern. However, > if you have a dual path e-bus, you can kill the > main bus and shut down a runaway pump motor while > retaining the electro-whizzies needed for comfortable > completion of flight. The float manufacturer (Montana) supplies the pump and control circuitry already mounted. The relays are Bosch 12V/20A 0 332 209 137 The diagram shows a 25A pullable breaker feeding the relays. A 1A fuse protects the relay control wiring. So a pullable breaker would be a convenient way to deal with a stuck relay or a defective pressure switch. That is perhaps what I should do. I will be interested in the results of your discussions with Klaus about powering the Lightspeed ignition. I know two people who are about to install these. Thanks again for all the great advice. Even while lurking, I learn something new and useful every week ! Jeff Page Dream Aircraft Tundra #10


    Message 11


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    Time: 12:57:00 PM PST US
    From: <longg@pjm.com>
    Subject: Re: Fuses instead of breakers
    I tried the "fuse" test once. The test was to install the P-III with a fuse and see if I could guess where I might be when it fails. Mine failed on the run-up pad. I promptly pulled up to the hangar and wired it directly to the battery per Klaus's instructions. I always figured he wrote them for a reason. Been working ever since. I mounted mine upside down on the bottom of the avionics panel where they get plenty of fresh air. Best Wishes, Glenn -----Original Message----- From: owner-aeroelectric-list-server@matronics.com [mailto:owner-aeroelectric-list-server@matronics.com] On Behalf Of bcondrey Sent: Thursday, January 26, 2012 3:01 PM Subject: AeroElectric-List: Re: Fuses instead of breakers FWIW, this subject has been discussed before on the AeroElectric list. Use the search function for the words "Klaus" and "crowbar" and you'll find a couple threads from early 2009. Turns out that it's not just over-voltage events that will cause them to crowbar but apparently over-temp. This was posted on Feb 1, 2009: "I have had to do one inflight reset on the Plasma III on one system once. The reset was successful and power was restored to the unit. I removed the unit and sent it back to Klaus for inspection. The fault was determined to be an overheat situation. That unit was located in an area without any real ventilation and without an form of cooling while operation in Arizona during the summer. the compartment temp was estimated to have exceeded 200 deg. F. The unit was modified to the latest version (lower heat output components and a ventilation port. The aircraft was modified to provide air circulation in that compartment. After 300+ hours on that unit no faults noted. The point, when the unit faulted it tripped the CB and was then reset and provided service throughout the remainder of that flight. " Without getting into the discussion of whether the design should or shouldn't be modified, my purpose on posting (now and back in early 2009) is simply to make those with dual LSE ignition setups aware that fuses can't be arbitrarily substituted for CBs in this case. Bob C Read this topic online here: http://forums.matronics.com/viewtopic.php?p=364895#364895


    Message 12


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    Time: 03:44:22 PM PST US
    From: Ed Holyoke <bicyclop@pacbell.net>
    Subject: Re: Fuses instead of breakers
    I'll try and find it. I know that Klaus is adamant about having a breaker and not a fuse. Ed On 1/25/2012 9:56 AM, Robert L. Nuckolls, III wrote: > At 11:24 AM 1/25/2012, you wrote: > Just one more thing to think about if you are doing this with a > Lightspeed ignition. From what I've read, there is some sort of > crowbar inside the ignition module to protect it from an overvoltage > event. If a fuse is fitted and the crowbar kicks it, you'll not be > able to reset it as easily as with a breaker - if you can reach the > fuse at all. I've heard of at least one case where an airplane was > brought down because it was wired differently than the installation > instructions in that regard. > > Can you elaborate on what you've read and give us sources? > I'm unaware of any crowbar ov protection built into the > LSE system. Is this called out in any of their published > literature? I found this on the Lightspeed site: > ------------------------ > Electrical System Requirements > > All Plasma CDI systems can be used with 12 or 24 volt electrical > systems. Input voltages above 35 volts or reversed polarity can cause > system damage. > > For this reason it is mandatory that all aircraft using Plasma CD > Ignitions are equipped with over-voltage protection in their > alternator charging system(s). Over-voltage protection is a > requirement for certified aircraft. Power connection must be directly > to the battery terminals to avoid voltage spikes and electrical > noise. Aluminum should never be used as an electrical conductor for > the Plasma CDI. Use only the supplied aircraft quality stranded wire. > > Minimum supply voltage for starting is 6.5 Volts. > > Minimum operating voltage is 5.5 Volts. > -------------------------- > This statement argues against any built-in ov > protection. At the same time, the very wide operating > voltage for the system guarantees that a properly > designed 14v system will NEVER offer a threat to > the LSE system. > > I am presently participating in an analysis of > cause and effect for simultaneous failure of > dual LSE systems. Root cause for that event > was a failure to craft a failure tolerant > architecture . . . a design goal which is foundation > for all efforts here on the AeroElectric-List. > > It's a certainty that no builder who participates > here on the List will suffer such an event. > > Bob . . . > > * > > > *


    Message 13


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    Time: 05:02:14 PM PST US
    From: "Robert L. Nuckolls, III" <nuckolls.bob@aeroelectric.com>
    Subject: Re: Fuses instead of breakers
    At 02:43 PM 1/26/2012, you wrote: At 04:27 PM 1/25/2012, you wrote: I merely meant that a 5A fuse and a 5A breaker behave differently, but since the protection type is not specified, the rule could be interpreted as a maximum of a 5A fuse. Oh absolutely. The fact that such a level was given without an accompanying I(squared)T time constant goes to suggest the arbitrary nature of the value. As we've discussed here before, seeing a 5A number on a protective device is a small bit of knowledge about how the device performs. I'd have to go arm-wrestle with dragons to get a 10A fuse attached to a battery bus in a TC aircraft . . . but you and I know that a 10A ATC fuse is faster than a miniature 5A breaker and is . . . therefore . . . a rational crash safety substitute for always-hot feeders. What controls the pump motor . . . a contactor? The float manufacturer (Montana) supplies the pump and control circuitry already mounted. The relays are Bosch 12V/20A 0 332 209 137 The diagram shows a 25A pullable breaker feeding the relays. A 1A fuse protects the relay control wiring. So a pullable breaker would be a convenient way to deal with a stuck relay or a defective pressure switch. That is perhaps what I should do. Agreed. Those relays are not specifically crafted for motor control service. Having a crew-operated means by which a runaway can be controlled seems prudent. I will be interested in the results of your discussions with Klaus about powering the Lightspeed ignition. I know two people who are about to install these. There are no doubt many hundreds if not thousands of these flying. To the best of my knowledge, they are not "special" devices deserving of extra-ordinary attention. Discussions not withstanding, the published current draw values for LSE products say that the greatest current draw for a 6-cylinder system is 2.1A at 13.8 volts. Emacs! Given that the device features a switchmode power supply with a wide range of operating voltages, we know that this is a constant-power mode of operation. So 2.1 x 13.8 sez the critter needs right at 30 watts for operation at MAX RPM. One can expect the current to climb as voltage goes down . . . so if you're operating battery only and the battery is down on that 11-volt-slide- to-darkness, the ignition system current will have risen to something around 2.7 amps. Likewise, operating current on a 29 volt bus will be down around 1.0 amps. The 4-Cylinder systems are still more frugal in their demands on the electrical system. Thanks again for all the great advice. Even while lurking, I learn something new and useful every week ! Thanks for getting involved and asking. It's through EXCHANGES of observation and events that I learn useful things too. Folks have often asked why the 'Connection is up to Revision 12 in "just 23 years of publication". I tell them that my education came from a collaboration with colleagues who spoke engineereze. And we hammered on a different class of airplane. When I sat down to do the first chapters of the 'Connection, I realized that I could not answer questions without knowing what the questions are. Further, they needed to be written in OBAMeze. It's the collective participation of all the builders on the List/emails/telephone/ seminars that drive what goes into the next revision. It's truly a work in progress that would not have happened without this join venture arena. Bob . . .


    Message 14


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    Time: 05:21:48 PM PST US
    From: "Robert L. Nuckolls, III" <nuckolls.bob@aeroelectric.com>
    Subject: Re: Fuses instead of breakers
    >Without getting into the discussion of whether the design should or >shouldn't be modified, my purpose on posting (now and back in early >2009) is simply to make those with dual LSE ignition setups aware >that fuses can't be arbitrarily substituted for CBs in this case. I would agree that when the installed system is at risk for an event triggered by conditions of installation and/or manufacturing mod levels then the system is indeed still 'experimental'. Now that the 'student installer' has graduated from the lab to the working environment, I'll suggest that the risk for substitution is microscopically low. This is something that we must always keep in mind. Instructions and ratings are important. When in doubt, go measure it. It's entirely possible that the builder who experienced this event might not have survived to give us his particular dark-n-stormy-night narrative. We wouldn't be having this discussion about that particular event . . . indeed we wouldn't even know the details. But the fact is that he DID experience a trip in a critical system power feeder which prompted further investigation and he shared his discovery with the rest of us. That information goes to making us MORE confident, not less. I recall a discussion here on the list a some time back where wires in the wreckage were found pulled out of the terminal crimps. Hmmm . . . we'll never know if this failure-to-follow the instructions precipitated the event . . . but the overt evidence of failure in craftsmanship does raise valid questions. So if one chooses to explore departures from published instructions, any such departure needs to be considered carefully. It's not difficult, just rigorous. Get on the List and let's talk about it. Bundle all the concerns together and develop a plan to morph an experiment into a recipe for success. But if you don't want to be an explorer or crafter of new recipes, that's fine too. The vast majority of our brothers building OBAM aircraft are not explorers and the last thing they want to do is experiment. This venue for acquiring a personally owned aircraft recognizes that too. Most never frequent this List and don't need to . . . their relationship with their airplane's electrical system is no different than the average spam can driver in a 172 . . . and that's okay. Bob . . .


    Message 15


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    Time: 06:57:24 PM PST US
    From: "Stuart Hutchison" <stuart@stuarthutchison.com.au>
    Subject: Larger D-Sub pins
    Thanks Bob, Good idea. I think I'll go ahead and make a parallel wire loom now, then replace it with a PCB later (when I have more time) ... after all, we never really stop working on our boys toys do we !! :) Thanks Bruce, My circuit tracks out to a TCW Safety Trim and TCW Intelligent Flap Controller, so the flaps can't be oversped (i.e. they can't be extended above 95kts) and my stick grip start button is off to the right where it's out of the way of my fat fingers A taildragger F1 Rocket is capable of dragging itself across the ground (braked) at about 2000 RPM and is relatively easy to tip over, so I want one hand on the throttle and one hand holding the stick right back during start. All of the copilot stick functions can be turned off by the pilot to avoid back seat embarrassments. Cheers, Stu _____ From: owner-aeroelectric-list-server@matronics.com [mailto:owner-aeroelectric-list-server@matronics.com] On Behalf Of Robert L. Nuckolls, III Sent: Friday, January 27, 2012 4:25 AM Subject: RE: AeroElectric-List: Larger D-Sub pins At 06:24 AM 1/26/2012, you wrote: Thanks for your help everyone. I thought it would also be more convenient to use 18AWG pins for this reason (but I haven't tried removing them). Hmmm . . . hadn't thought about that. I'm not sure they CAN be removed with the legacy extraction tools. Given the complexity of your stick grip wiring I think I would give serious thought to building an etched circuit board for the relay-deck and stick-grip-junction- box. Your mating connectors then solder to the board. The board can mount the relays and perhaps a speed adjustment system. the mating connectors get 'really clean' with respect to materials and techniques. Express PCB has free software and really reasonable prices on double-sided, plated-thru boards laid up and ordered via your computer. Emacs! Bob . . .




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