---------------------------------------------------------- AeroElectric-List Digest Archive --- Total Messages Posted Tue 12/12/17: 9 ---------------------------------------------------------- Today's Message Index: ---------------------- 1. 07:50 AM - Re: Bose ANR Jacks and Grounding, Alternator AC Limits (Airdog77) 2. 07:55 AM - Re: stacking ring terminals or ? (user9253) 3. 08:58 AM - Re: diode vs snapjack (Robert L. Nuckolls, III) 4. 09:31 AM - Re: Re: stacking ring terminals or ? (Ken Ryan) 5. 09:38 AM - Re: diode vs snapjack (Ken Ryan) 6. 10:09 AM - Re: diode vs snapjack (Robert L. Nuckolls, III) 7. 10:51 AM - Re: stacking ring terminals or ? (user9253) 8. 05:38 PM - Re: AeroElectric-List Digest: Garmin SL-30 (Dean Psiropoulos) 9. 08:25 PM - Re: Constructing an automatic RCA video camera feed splitter (Eric Page) ________________________________ Message 1 _____________________________________ Time: 07:50:58 AM PST US Subject: AeroElectric-List: Re: Bose ANR Jacks and Grounding, Alternator AC Limits From: "Airdog77" Roger... Thanks Don! I'm attempting to keep good notes on what you have done for possible troubleshooting later on. -------- Airdog Wade Parton Building Long-EZ N916WP www.longezpush.com Read this topic online here: http://forums.matronics.com/viewtopic.php?p=476356#476356 ________________________________ Message 2 _____________________________________ Time: 07:55:22 AM PST US Subject: AeroElectric-List: Re: stacking ring terminals or ? From: "user9253" Ken, The rectifier/regulator output will be unstable without a battery. The voltage will fluctuate plus and minus about one volt. At least it did in my Rotax powered RV-12 without the battery connected. Maybe your Silent-Hektik regulator will do better. Even if the voltage is unstable, chances are that the fuel pump will still operate normally. The capacitor does not seem to help much. -------- Joe Gores Read this topic online here: http://forums.matronics.com/viewtopic.php?p=476357#476357 ________________________________ Message 3 _____________________________________ Time: 08:58:35 AM PST US From: "Robert L. Nuckolls, III" Subject: Re: AeroElectric-List: diode vs snapjack At 03:54 PM 12/11/2017, you wrote: >Which is better for use on relays, the "standard" diode or the >"snapjack" (bi-directional zener transient voltage suppressor)? > >Ken Diodes are fine . . . there were some lengthy discussions on the 'advantages' of voltage compliant spike suppression about 10 years. A great deal of homage was paid to a document published by Tyco no less wherein the author claimed that hard clamping of the coil spike by diode slowed contact spreading velocity and increased wear and tear on the relay. Yes, the diode causes a DELAY in the first motion of the opening contacts . . . but before the contacts start to move, an AIR GAP is introduced into the magnetic circuit that generates the closing force. This air gap has many times more effect on contact spreading velocity than does the decay rate of current in the coil. The Tyco author laid all his eggs in the magnetic force decay due to current in the coil and totally ignored the air gap effects. A simple workbench experiment would have illuminated his attribution error for cause/effect. I spent a few years sifting the sands of relay performance and failures at Beech. Many of the young bucks wearing the boots of their predecessors as engineering reps for relay and contactor manufacturers were glaringly deficient in mentorship by those predecessors . . . Bob . . . ________________________________ Message 4 _____________________________________ Time: 09:31:56 AM PST US From: Ken Ryan Subject: Re: AeroElectric-List: Re: stacking ring terminals or ? Joe, I followed your testing. Most people I have talked to agree with you that the fuel pump should perform normally even with the unstable voltage. It will be interesting to see what happens. The Silent-Hektik calls for a larger 33000 capacitor. I wonder if a larger capacitor might smooth out the Ducati. Speaking of capacitors, I spent some time yesterday trying to figure out which one to buy for the Silent-Hektik reg/rect. The selection is mind boggling. I currently have a 22000 purchased from B&C. It is a Mallory which apparently is made by Cornell Dubilier. Based on that I came up with this one for the Silent-Hektik: [link to mouser]. Do you think this is the right one? Is there any reason that I could not use the 33000 with the Ducati reg/rect? For those interested in the Silent-Hektik, it looks like they have changed the charging profile to be more friendly with lithium batteries. Here is a google translation of some text from their website talking about this new charging profile: The Silent Hustle 5Step charging technology for lithium-ion batteries The new controller can be used by the 5Step charging technology as well as for previous lead batteries, but especially for the modern ion batteries. The ion batteries have the advantage of delivering a very high starting current for small hubs and low weight. However, this low battery impedance has a serious disadvantage when charging. After starting the battery is dead and it can float well over 20A. Therefore, the ion battery is initially pre-charged with 13V, which significantly reduces the initial charging current and overheating. Then with five steps in about 30 minutes to 14.2V gently recharged. After 90 minutes, then on trickle loading switched. This is a perfect ion battery charging management with charging current control that reduces overheating and overcharging to 90%. The development of the new regulator was carried out in our house with A123 LiFePO4 cells, 14V 7.5Hh, and is recommended as a very reliable lithium-ion starter battery. Ken On Tue, Dec 12, 2017 at 6:54 AM, user9253 wrote: > > Ken, The rectifier/regulator output will be unstable without a battery. > The voltage will fluctuate plus and minus about one volt. At least it did > in my Rotax powered RV-12 without the battery connected. Maybe your > Silent-Hektik regulator will do better. Even if the voltage is unstable, > chances are that the fuel pump will still operate normally. The capacitor > does not seem to help much. > > -------- > Joe Gores > > > Read this topic online here: > > http://forums.matronics.com/viewtopic.php?p=476357#476357 > > ________________________________ Message 5 _____________________________________ Time: 09:38:52 AM PST US From: Ken Ryan Subject: Re: AeroElectric-List: diode vs snapjack Thanks Bob. Is there any disadvantage to the snapjacks? On Tue, Dec 12, 2017 at 7:57 AM, Robert L. Nuckolls, III < nuckolls.bob@aeroelectric.com> wrote: > At 03:54 PM 12/11/2017, you wrote: > > Which is better for use on relays, the "standard" diode or the "snapjack" > (bi-directional zener transient voltage suppressor)? > > Ken > > > Diodes are fine . . . there were some lengthy discussions > on the 'advantages' of voltage compliant spike suppression > about 10 years. A great deal of homage was paid > to a document published by Tyco no less wherein the author > claimed that hard clamping of the coil spike by diode > slowed contact spreading velocity and increased wear and > tear on the relay. > > Yes, the diode causes a DELAY in the first motion > of the opening contacts . . . but before the contacts > start to move, an AIR GAP is introduced into the > magnetic circuit that generates the closing force. > This air gap has many times more effect on contact > spreading velocity than does the decay rate of current > in the coil. > > The Tyco author laid all his eggs in the magnetic > force decay due to current in the coil and totally > ignored the air gap effects. A simple workbench > experiment would have illuminated his attribution > error for cause/effect. > > I spent a few years sifting the sands of relay performance > and failures at Beech. Many of the young bucks wearing the > boots of their predecessors as engineering reps for relay > and contactor manufacturers were glaringly deficient in > mentorship by those predecessors . . . > > Bob . . . > ________________________________ Message 6 _____________________________________ Time: 10:09:19 AM PST US From: "Robert L. Nuckolls, III" Subject: Re: AeroElectric-List: diode vs snapjack At 11:37 AM 12/12/2017, you wrote: >Thanks Bob. Is there any disadvantage to the snapjacks? costs more Bob . . . ________________________________ Message 7 _____________________________________ Time: 10:51:53 AM PST US Subject: AeroElectric-List: Re: stacking ring terminals or ? From: "user9253" I am not an expert on capacitors, so maybe someone more knowledgeable will chime in. I do not think replacing the 22,000 microfarad capacitor with a 33000 will affect the Ducati regulator. I don't know how much good a capacitor does in smoothing out the voltage. A capacitor would have to accept and store a whole lot of electrons being pushed out by the dynamo voltage peaks. And then the capacitor would have to supply that stored energy to the pump motor during voltage sags. The capacitor just doesn't seem big enough compared to the size of dynamo and motor. If the capacitor is big enough, then why is the voltage unstable when the battery is disconnected? -------- Joe Gores Read this topic online here: http://forums.matronics.com/viewtopic.php?p=476364#476364 ________________________________ Message 8 _____________________________________ Time: 05:38:31 PM PST US From: "Dean Psiropoulos" Subject: AeroElectric-List: RE: AeroElectric-List Digest: Garmin SL-30 Andy: I bought an SL-30 brand new when I was building my RV but it sat on the shelf for 5 years before the airplane flew. I did the wiring of the airplane, which has a full IFR stack of UPS AT gear. The radio received well but had a bit of scratchy transmission and there were a couple times that I noticed it causing my electric pitch trim to move when I keyed the Mike. Also, I have a comant dual element VOR/ILS antenna under the vertical stabilizer on the bottom of the fuselage. While this would seem like a good place to put it, my VOR reception has not been great out past 25 miles or so from a VOR. Spotty between 20 and 25 but rock solid below 20 miles out (3500 MSL). Since most VORs are supposed to be good for about 40 miles out and I live in the flat lands of Florida this is a bit disconcerting. The radio display quit working around 200 hours and Garmin fixed it, only to have it crap out again about 6 months later (Garmin fixed it free the second time). Later I did find that the coax connector to my bent whip (com) antenna was not crimped well and replaced it, seemed to cure the pitch trim interference but transmission still scratchy. VOR reception about the same, I inspected both ends of the coax and connectors but can't see anything obvious. I assume if the COAX or connectors were shorted I wouldn't get any reception on the Nav at all. I did use RG-58 and it's a long run from the instrument panel down the firewall and the length of the fuselage to the VOR antenna so maybe there is a bit too much attenuation there to get a full 40 mile reception range. I'm going to rework the radio stack to put in a new ADS-B out transponder and I think I'll replace the RG-58 with RG-400 to see if that helps. My GX-65 GPS/COM radio works fine and it also uses RG-58 to the bent whip and has an Icom splitter box in the line (for plugging a handheld into the bent whip when an electrical or complete COM radio failure occurs). So...I use the SL-30 for AWOS/ATIS reception and ground control and the GX-65 for air to air/ground. Given what the SL-30 cost it's a little disappointing but the avionic shop (Gulf Coast avionics in Lakeland FL has a test fixture for UPS AT gear) plugged it into their test fixture and said that there is nothing wrong with the radio so all I can think is that the wiring may be the issue. Have not tried installing an SWR meter in the line, might give a better clue but the bent whip has no way to adjust SWR so I don't know how I would fix that if it was a problem (the GX-65 uses the same brand of bent whip for COM so I don't know why the SL-30 would have a problem). Just some data points from my experience, let me know if you find out anything on your setup. Regards Dean Psiropoulos RV-6A N197DM Tarpon Springs, FL ________________________________ Message 2 _____________________________________ Time: 08:04:30 AM PST US From: "Andy Elliott" Subject: AeroElectric-List: Debug plan for flaky NavCom operation? I have recently purchased an RV with an SL-30 as the #2 radio. Operation of this radio is very inconsistent. Typically on the ground on battery power I get good reception and transmission on local frequencies. Sometime after engine start, I pick up a *lot* of background static on some, but not all, frequencies. At least on the ground, I can still talk and receive on these frequencies, overcoming the static. But in the air, this radio is very flaky, both com and nav. Sometimes it seems to work OK, but sometimes I can't receive the local ATIS from 10 miles away when it is clear on the #1 radio. The static sometimes is there and sometimes not. Sometimes the VOR reception is good and correct, and sometimes it loses lock or report an obviously wrong radial. (I haven't tried the ILS yet.) My first thought was that there must be a bad ground somewhere, but before going in with the flashlight and meter (which is not a trivial process, of course), and before considering pulling the radio and having it tested (Garmin's flat repair prices are $$$.), I thought I would try to get a debug plan from the group here. Basically, I need a sequence of things to check in order, hopefully going from simple to more difficult, which would lead to (a) resolution of the problem or (b) a decision to send the radio for check/repair. Anyone have such a plan?? Thanks, Andy Elliott -------------------------- Andy Elliott, RV-8, N303RV CL: 480-695-9568 ________________________________ Message 9 _____________________________________ Time: 08:25:31 PM PST US Subject: AeroElectric-List: Re: Constructing an automatic RCA video camera feed splitter From: "Eric Page" Components for the video mux arrived today. The DB-25 backshell has four small plastic bosses inside each half to locate the included cable clamp; these are easily removed with a small flush cutter or X-Acto blade. I made a CAD template for the PCB to fit this backshell and the DB-25 connector, then printed it at 100% and cut it out to verify fitment. Pads for the connector's solder cups align well and the PCB fills the shell nicely. Drawing is attached. My PCB layout for the mux will need a little finessing to fit this board outline, which I'll do in the next couple of days. I expect to have boards ordered by Fri, then I'll assemble one and send it to Alec for firmware testing. Eric Read this topic online here: http://forums.matronics.com/viewtopic.php?p=476370#476370 Attachments: http://forums.matronics.com//files/norcomp_956_025_010r031_191.jpg http://forums.matronics.com//files/db_25_pcb_blank_106.pdf ------------------------------------------------------------------------------------- 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.