---------------------------------------------------------- AeroElectric-List Digest Archive --- Total Messages Posted Wed 07/27/05: 14 ---------------------------------------------------------- Today's Message Index: ---------------------- 1. 11:58 AM - Noise from strobe PS (Matt Jurotich) 2. 12:02 PM - So where's my award? (Eric M. Jones) 3. 12:20 PM - Re: Noise from strobe PS (Charlie England) 4. 12:29 PM - Re: So where's my award? (Vern W.) 5. 12:45 PM - Re: overvoltage protection false trigger fix (Ken) 6. 12:46 PM - Re: So where's my award? (Hinde, Frank George (Corvallis)) 7. 02:58 PM - Re: So where's my award? (Robert L. Nuckolls, III) 8. 03:10 PM - Re: overvoltage protection false trigger fix (Robert L. Nuckolls, III) 9. 03:40 PM - Re: Noise from strobe PS (Robert L. Nuckolls, III) 10. 05:00 PM - Re: So where's my award? (Paul Messinger) 11. 08:39 PM - Re: PTT coiled cord (Dino Bortolin) 12. 09:06 PM - Re: Re: PTT coiled cord (Robert L. Nuckolls, III) 13. 10:58 PM - Paul Messinger (Gerry Holland) 14. 11:39 PM - Re: So where's my award? (Robert L. Nuckolls, III) ________________________________ Message 1 _____________________________________ Time: 11:58:56 AM PST US From: Matt Jurotich Subject: AeroElectric-List: Noise from strobe PS --> AeroElectric-List message posted by: Matt Jurotich I am part owner of a 1977 Piper Archer. When I turn on the strobes for a ground check I hear a loud variable frequency tone. My partners say it normal, it is just the capacitor charging. They also say it has been there always but I just noticed the noise in the last few flights. It is in the frequency range where my hearing is most degraded so it may have been present at a much lower volume. Is the noise normal? Electrons moving into a capacitor causing noise seems strange. Thanks Matthew M. Jurotich e-mail mail to: phone : 301-286-5919 ________________________________ Message 2 _____________________________________ Time: 12:02:02 PM PST US From: "Eric M. Jones" Subject: AeroElectric-List: So where's my award? --> AeroElectric-List message posted by: "Eric M. Jones" >>> I'm adding a new feature to aeroelectric.com that will showcase this experience as the first of what I hope will become a long series of exchanges between two or more individuals here on the list where a simple (but profound) idea comes to light with benefits to anyone who chooses to exploit it. I'll catalog and archive the posts that describe these experiences as a special new feature. Individual(s) contributions will be acknowledged by addition of the thread to the archive and issuance of Certificates of Recognition issued by the AeroElectric Connection. I'll reserve the right to make final determination and selection of items to be so recognized but I encourage ANY participant on the AeroElectric-List to nominate any simple-idea and discussion participants for special recognition. The first certificate of this series has been posted in your name and may be downloaded from http://www.aeroelectric.com/Awards/Certificates/001_Ken_Lehman.pdf Thank you so much for sharing your insight and skills on the AeroElectric List. Bob . . . >>> Dearest Robert-- Thou hast erred.....you have made the mistake of a loving father who gives a treat to one of his twelve (hundred) children without giving an equivalent treat to the rest. You have put yourself into a predicament with all good intentions, but a predicament nevertheless: 1) What about the ugly child...over there...who is REALLY right but has no social graces? 2) Now your students are going to play for your approval. Reasonable discourse goes out the window. 3) You now carry the risk that people won't want to disagree with you because they will have NO CHANCE of gaining your approval. 4) You have automatically set up the "I stuck it to Bob award". 5) Whenever I got an award at work, I knew the guys upstairs were getting bonuses. How about cutting us in? 6) It cheapens the whole idea of intellectual discussion. 7) You want slow pitches and softballs? You'll get slow pitches and softballs. 8) Every leader worth his salt has one guy who tells him not to pee in the soup. Okay, so now give me an award to suggest that you kill the award system. Permanently. And don't pee in the soup. Regards, Eric M. Jones www.PerihelionDesign.com 113 Brentwood Drive Southbridge MA 01550-2705 (508) 764-2072 " I would have made a good Pope." -- Richard M. Nixon (1913-1994) ________________________________ Message 3 _____________________________________ Time: 12:20:14 PM PST US From: Charlie England Subject: Re: AeroElectric-List: Noise from strobe PS --> AeroElectric-List message posted by: Charlie England Matt Jurotich wrote: >--> AeroElectric-List message posted by: Matt Jurotich > >I am part owner of a 1977 Piper Archer. When I turn on the strobes for a >ground check I hear a loud variable frequency tone. My partners say it >normal, it is just the capacitor charging. They also say it has been there >always but I just noticed the noise in the last few flights. It is in the >frequency range where my hearing is most degraded so it may have been >present at a much lower volume. Is the noise normal? Electrons moving >into a capacitor causing noise seems strange. > >Thanks > > >Matthew M. Jurotich > >e-mail mail to: >phone : 301-286-5919 > What they probably meant (even if they didn't know it) was that you are hearing the artifacts of the oscillator frequency in the switching power supply that charges the capacitor at several hundred volts. ________________________________ Message 4 _____________________________________ Time: 12:29:46 PM PST US From: "Vern W." Subject: Re: AeroElectric-List: So where's my award? --> AeroElectric-List message posted by: "Vern W." C'mon Eric, it looks like you've bought into the Liberal "everyone has to feel good identically" concept. It's clear that all Bob's trying to do is to allow others to learn from other's examples. I don't see any of the rest of the strange things that you suggest might happen, happening. Do you have some kind of obsession with Bob? :-) Vern ----- Original Message ----- From: "Eric M. Jones" Subject: AeroElectric-List: So where's my award? > --> AeroElectric-List message posted by: "Eric M. Jones" > > >>> I'm adding a new feature to aeroelectric.com that will showcase > this experience as the first of what I hope will become a long > series of exchanges between two or more individuals here on > the list where a simple (but profound) idea comes to light > with benefits to anyone who chooses to exploit it. > > I'll catalog and archive the posts that describe these > experiences as a special new feature. Individual(s) > contributions will be acknowledged by addition of the > thread to the archive and issuance of Certificates of > Recognition issued by the AeroElectric Connection. > > I'll reserve the right to make final determination and > selection of items to be so recognized but I encourage > ANY participant on the AeroElectric-List to nominate > any simple-idea and discussion participants for > special recognition. > > The first certificate of this series has been posted in your > name and may be downloaded from > > http://www.aeroelectric.com/Awards/Certificates/001_Ken_Lehman.pdf > > Thank you so much for sharing your insight and skills on > the AeroElectric List. > > Bob . . . >>> > > Dearest Robert-- > > Thou hast erred.....you have made the mistake of a loving father who gives a > treat to one of his twelve (hundred) children without giving an equivalent > treat to the rest. You have put yourself into a predicament with all good > intentions, but a predicament nevertheless: > > 1) What about the ugly child...over there...who is REALLY right but has no > social graces? > > 2) Now your students are going to play for your approval. Reasonable > discourse goes out the window. > > 3) You now carry the risk that people won't want to disagree with you > because they will have NO CHANCE of gaining your approval. > > 4) You have automatically set up the "I stuck it to Bob award". > > 5) Whenever I got an award at work, I knew the guys upstairs were getting > bonuses. How about cutting us in? > > 6) It cheapens the whole idea of intellectual discussion. > > 7) You want slow pitches and softballs? You'll get slow pitches and > softballs. > > 8) Every leader worth his salt has one guy who tells him not to pee in the > soup. > > Okay, so now give me an award to suggest that you kill the award system. > Permanently. And don't pee in the soup. > > Regards, > Eric M. Jones > www.PerihelionDesign.com > 113 Brentwood Drive > Southbridge MA 01550-2705 > (508) 764-2072 > > " I would have made a good Pope." > -- Richard M. Nixon (1913-1994) > > ________________________________ Message 5 _____________________________________ Time: 12:45:58 PM PST US From: Ken Subject: Re: AeroElectric-List: overvoltage protection false trigger fix --> AeroElectric-List message posted by: Ken Well that made my day! We are going to have to start using the spell checker if such prestigious awards are on the line now though ;) Glad I could return something useful to the group. I'm humbled - as no one has been more generous with his time and efforts here than Bob and it is Bob who has put his designs in the public domain for us... There was also a one liner buried in that post. When I realized that the OVM with a 2.5 amp C/B was not blowing a 10 amp fuse despite numerous activations, it put to rest any minor concerns I might have had about extraordinary crowbar trip currents. I rather expected that the fuses would blow but I was using 18 awg wire and before making up fuselinks I thought I'd try feeding it off fuses and using the 2.5 amp breakers. I will leave it that way. Ken snip >> Interestingly both >>C/B's are in series with a 10 amp ATO fuse and despite many dozens of >>2.5 amp C/B trips I've yet to pop a 10 amp fuse. >> ________________________________ Message 6 _____________________________________ Time: 12:46:01 PM PST US Subject: RE: AeroElectric-List: So where's my award? From: "Hinde, Frank George (Corvallis)" --> AeroElectric-List message posted by: "Hinde, Frank George (Corvallis)" Oh I dunno Eric...Personally I would be honoured to get a "Bob award". I also know the likelyhood of getting one is practically zero...Then again as a Mechanical Engineer it's a goal I aspire too...:) Frank Do not archive -----Original Message----- From: owner-aeroelectric-list-server@matronics.com [mailto:owner-aeroelectric-list-server@matronics.com] On Behalf Of Eric M. Jones Subject: AeroElectric-List: So where's my award? --> AeroElectric-List message posted by: "Eric M. Jones" --> >>> I'm adding a new feature to aeroelectric.com that will showcase this experience as the first of what I hope will become a long series of exchanges between two or more individuals here on the list where a simple (but profound) idea comes to light with benefits to anyone who chooses to exploit it. I'll catalog and archive the posts that describe these experiences as a special new feature. Individual(s) contributions will be acknowledged by addition of the thread to the archive and issuance of Certificates of Recognition issued by the AeroElectric Connection. I'll reserve the right to make final determination and selection of items to be so recognized but I encourage ANY participant on the AeroElectric-List to nominate any simple-idea and discussion participants for special recognition. The first certificate of this series has been posted in your name and may be downloaded from http://www.aeroelectric.com/Awards/Certificates/001_Ken_Lehman.pdf Thank you so much for sharing your insight and skills on the AeroElectric List. Bob . . . >>> Dearest Robert-- Thou hast erred.....you have made the mistake of a loving father who gives a treat to one of his twelve (hundred) children without giving an equivalent treat to the rest. You have put yourself into a predicament with all good intentions, but a predicament nevertheless: 1) What about the ugly child...over there...who is REALLY right but has no social graces? 2) Now your students are going to play for your approval. Reasonable discourse goes out the window. 3) You now carry the risk that people won't want to disagree with you because they will have NO CHANCE of gaining your approval. 4) You have automatically set up the "I stuck it to Bob award". 5) Whenever I got an award at work, I knew the guys upstairs were getting bonuses. How about cutting us in? 6) It cheapens the whole idea of intellectual discussion. 7) You want slow pitches and softballs? You'll get slow pitches and softballs. 8) Every leader worth his salt has one guy who tells him not to pee in the soup. Okay, so now give me an award to suggest that you kill the award system. Permanently. And don't pee in the soup. Regards, Eric M. Jones www.PerihelionDesign.com 113 Brentwood Drive Southbridge MA 01550-2705 (508) 764-2072 " I would have made a good Pope." -- Richard M. Nixon (1913-1994) ________________________________ Message 7 _____________________________________ Time: 02:58:29 PM PST US From: "Robert L. Nuckolls, III" Subject: Re: AeroElectric-List: So where's my award? --> AeroElectric-List message posted by: "Robert L. Nuckolls, III" At 03:01 PM 7/27/2005 -0400, you wrote: >--> AeroElectric-List message posted by: "Eric M. Jones" > > >>> I'm adding a new feature to aeroelectric.com that will showcase > this experience as the first of what I hope will become a long > series of exchanges between two or more individuals here on > the list where a simple (but profound) idea comes to light > with benefits to anyone who chooses to exploit it. > >Dearest Robert-- > >Thou hast erred.....you have made the mistake of a loving father who gives a >treat to one of his twelve (hundred) children without giving an equivalent >treat to the rest. You have put yourself into a predicament with all good >intentions, but a predicament nevertheless: > >1) What about the ugly child...over there...who is REALLY right but has no >social graces. If it WERE a contest about so subjective a quality as beauty, then I would agree. But then, this isn't even a contest. It's my way of expressing my excitement over being made privy to a simple but profound idea. An idea that brought forward by the volunteer effort of an objective and skilled thinker. I have no idea how he would place in a Mr. Universe contest and it doesn't matter. I DO know how he places in the universe of teachers. >2) Now your students are going to play for your approval. Reasonable >discourse goes out the window. I'm mystified as to your reasoning. Throughout my career I've had tens of thousands of hours of reasonable discourse with hundreds of individuals wherein most shared a goal of improving on the common lot. Some of us have been rewarded from time to time for what a supervisor deemed an extra ordinary achievement. I once received a raise from $25k/yr to $35k/yr for my work that fixed a trim system problem on the entire fielded fleet of 30 series Lears. In times since, I sincerely hope I've not conducted myself in any way as to degrade my ability to participate in reasonable discourse. Further, I've not worked a job at any time since with a feeling of disappointment for not having achieved that kind of recognition again. Had I never received that reward, I cannot imagine that it would have influenced my career much. My greatest rewards come from the satisfaction of practicing my craft and the feedback I get from builders describing their satisfaction with the performance of their airplanes. Some individuals go through their educational efforts gleaning perfectly ordinary but still useful benefits from their experience . . . a few will graduate with honors for having demonstrated both and ability and a willingness to excel. How does bestowing honors on exemplary performance degrade reasonable discourse amongst those who are not so rewarded? >3) You now carry the risk that people won't want to disagree with you >because they will have NO CHANCE of gaining your approval. Anyone participating on this list with a goal of gaining my "approval" would be well advised to examine their return on investment for spending time here. There are over 1300 folks who watch this list and only a small fraction of those EVER hit the "send" button. Are they here to get my approval or are they here to build better understanding of a collection of simple-ideas by reading the words of the teachers among us? You ARE correct in that I don't foresee a flood of awards going up on the website . . . that WOULD cheapen the concept. But if folks are here on the List just to get a gold star on their fanny, they're going to have to seek it from somebody besides me. The whole purpose of the award was to illustrate exactly what constitutes a simple-idea and how such seemingly insignificant facts can be so important. I've worked problems in my career where missed opportunities to understand a one-dollar, simple-idea cost my company $millions$. I'm working two such problems right now. Perhaps it seems silly and self-serving to you that I would make such a fuss over Ken's little dissertation but it was a light-bulb-moment for me and I'm grateful that he took the time to explore it and to make us all aware. >4) You have automatically set up the "I stuck it to Bob award". How so? I don't visualize the mechanism at work here. Please do me the honor of "sticking it to Bob", I'd be grateful for the education. >5) Whenever I got an award at work, I knew the guys upstairs were getting >bonuses. How about cutting us in? What kind of "bonuses" are we talking about here? Mr. Lehman has received nothing more than my enthusiastic appreciation for illuminating something I missed when offering a design up to my readers for crafting a useful accessory to their electrical system. Paul (and to some extent you too) have commented on the "tendency to nuisance trip" for that circuit and have branded it unworthy of consideration by the prudent designer. B&C and I have sold thousands of those systems with an exceeding low rate of difficulty so I was mystified as to why your and/or Paul's experiences were so unrewarding. I had no way of knowing how many folks had tried the roll-yer-own but I DID receive what had to be a disproportionate number of unhappy feedback. Ken's work showed us exactly WHY the circuit as offered from my website is especially dv/dt vulnerable. It also prompted a study on my part to discover the differences between what we've sold and what numerous others have built. I would have been just as enthusiastic if you or Paul would have caught the design flaw and brought it to light. I have invited you both repeatedly to participate in the discovery, explanation and distribution of simple-ideas that help us move our craft forward. I have a standing invitation on my website for anyone to document any useful contribution for addition to the collective pile. I don't have anything from you or Paul to post there yet but I DO have something from Mr. Leyman. Ken's contribution is quite simple but profoundly significant in solving a years-old mystery concerning my implementation of the crowbar ov protection philosophy. >6) It cheapens the whole idea of intellectual discussion. Forgive me sir but for the life of me I cannot understand why. The List isn't a Loto, a contest or even a Madison Avenue approach to persuading anyone to purchase anything. This is a classroom where we all have opportunities to share the best we know how to do with others and help each other over the sand burrs and gravel piles. I'm sorry if you are insulted or find it objectionable for me (as one of many teachers on the List) to express enthusiasm over a "light-bulb-moment" and then encourage others to watch for similar events in their own thought processes. To me, this is the ULTIMATE example of intellectual success. The only way I can see to cheapen a discussion is to offer faulty reasoning, bad data or ideas un-supported by the repeatable experiment. These are dishonorable activities that cheapen everything they touch INCLUDING intellectual discussion. Please explain how the extra-ordinarily enthusiastic response to a good idea trashes intellectual discussion, I'd be pleased to know it. >7) You want slow pitches and softballs? You'll get slow pitches and >softballs. > >8) Every leader worth his salt has one guy who tells him not to pee in the >soup. > >Okay, so now give me an award to suggest that you kill the award system. >Permanently. And don't pee in the soup. I presume these are artful euphemisms for something profound but they escape me at the moment. Where's your award? Hmmmm . . . okay, since you asked. I'd like to see a piece published that describes the mechanism by which the alternator load-dump event occurs. We need to know how much energy the event is capable of delivering which means a discovery and discussion of amplitude, duration and waveshape of the load-dump event under various conditions of alternator speed and pre-load. I'd be pleased to offer a test plan that describes a suite of test conditions. I'd also like to see a discussion on where the energy comes from. Many have written on this list and elsewhere that it comes from a collapse of the magnetic field in the alternator's stator winding. If this were true, then the ordinary Transorb approach to load-dump mitigation would suffice and George wouldn't have popped any Transorbs in his experiments. My hypothesis suggests the pulse is generated by conversion of mechanical energy to electrical energy in an under-damped servo response of the voltage regulator. If my hypothesis prevails, then there are going to be cases where the simple Transorb approach are bound to fail due to designer's misidentification and miscalculation of the mechanism involved. The article should at least propose ways that the load-dump event can be controlled. For the moment I'll suggest that a combination of Transorbs and judicious tailoring of the alternator regulator response are called for. This was what I hypothesized several years ago and what I thought that you and Paul were going to go off and explore. We'll publish the piece on the List and invite critical review by anyone who can contribute to the "intellectual discussion". Of course, success of this effort depends on participant enthusiasm for discussion NOT being damped by your expectation of award. I presume that all the experiments you've conducted yielded data that would allow you to blow away the fog of mystery surrounding this phenomenon. Ken got a measly little Word-generated certificate and his name carved in the wall at the AeroElectric Hall of Fame. I'll cut you both certificates -AND- pay $500 for an article that cuts through the mystery of this oft discussed but never explained phenomenon. Please sir, "stick it to me". Bob . . . ________________________________ Message 8 _____________________________________ Time: 03:10:45 PM PST US From: "Robert L. Nuckolls, III" Subject: Re: AeroElectric-List: overvoltage protection false trigger fix --> AeroElectric-List message posted by: "Robert L. Nuckolls, III" At 03:45 PM 7/27/2005 -0400, you wrote: >--> AeroElectric-List message posted by: Ken > >Well that made my day! We are going to have to start using the spell >checker if such prestigious awards are on the line now though ;) oops! is there a spelling error on the certificate? I checked again and didn't see one. >Glad I could return something useful to the group. I'm humbled - as no >one has been more generous with his time and efforts here than Bob and >it is Bob who has put his designs in the public domain for us... > >There was also a one liner buried in that post. When I realized that the >OVM with a 2.5 amp C/B was not blowing a 10 amp fuse despite numerous >activations, it put to rest any minor concerns I might have had about >extraordinary crowbar trip currents. I rather expected that the fuses >would blow but I was using 18 awg wire and before making up fuselinks I >thought I'd try feeding it off fuses and using the 2.5 amp breakers. I >will leave it that way. That's another simple idea that I'd not had time to touch on. I recommend the fusible link upstream of a crowbar breaker because very early tests on a variety of breakers showed that SOME products had a I-squared*T constant much larger than a fuse several times the size. I've had builders report opening a 20A fuse upstream of a 5A breaker. The fusible link seemed the best one-solution-fits-all approach. I'm not surprised that your 10A fuse upstream of the 2.5 amp breaker is stable . . . a typical 2.5A miniature breaker has about .28 ohms max internal resistance while the 5A is only 0.07 ohms max and typically .04 ohms. It should be noted that not EVERYONE can expect the same results given variability of breakers offered but if you're using the miniature devices common to modern aircraft fabrication, odds are that your experiences will parallel Ken's. Bob . . . ________________________________ Message 9 _____________________________________ Time: 03:40:54 PM PST US From: "Robert L. Nuckolls, III" Subject: Re: AeroElectric-List: Noise from strobe PS --> AeroElectric-List message posted by: "Robert L. Nuckolls, III" At 02:19 PM 7/27/2005 -0500, you wrote: >--> AeroElectric-List message posted by: Charlie England > Charlie is right on. The transistorized power supply in your strobe system steps low voltage DC from ship's power up to the several hundreds of volts necessary to light up the tubes. The power supply's operating frequency is affected by load which is heaviest while recharging the flash capacitor and tapers off just before the next flash. This explains the upward sweep of the perceived noise synchronized with the flash rate of your strobe lights. Yes, this noise is VERY common in far too many airplanes and on behalf of my fellow engineers in the aircraft business, I apologize. If you owned an OBAM aircraft, the addition of some form of noise filter at the strobe supply might help. Also, insulating your headset and microphone jacks from the airframe ground at the panel might be useful. Bottom line is that it was easy to avoid by original design and not terribly hard to fix except for the regulatory roadblocks on your certified ship. If you're interested in the "outlaw fix", contact me directly at http://www.aeroelectric.com/bob.nuckolls/ Otherwise, you're required to submit your airplane and pocketbook to a properly authorized technician who may or may not know how to fix it . . . but you could have him give me a call and I'll try to help. Bob . . . >Matt Jurotich wrote: > > >--> AeroElectric-List message posted by: Matt Jurotich > > > > >I am part owner of a 1977 Piper Archer. When I turn on the strobes for a > >ground check I hear a loud variable frequency tone. My partners say it > >normal, it is just the capacitor charging. They also say it has been there > >always but I just noticed the noise in the last few flights. It is in the > >frequency range where my hearing is most degraded so it may have been > >present at a much lower volume. Is the noise normal? Electrons moving > >into a capacitor causing noise seems strange. > > > >Thanks > > > > > >Matthew M. Jurotich > > > >e-mail mail to: > >phone : 301-286-5919 > > >What they probably meant (even if they didn't know it) was that you are >hearing the artifacts of the oscillator frequency in the switching power >supply that charges the capacitor at several hundred volts. > > >-- > > >-- incoming mail is certified Virus Free. Bob . . . -------------------------------------------------------- < Throughout history, poverty is the normal condition > < of man. Advances which permit this norm to be > < exceeded -- here and there, now and then -- are the > < work of an extremely small minority, frequently > < despised, often condemned, and almost always opposed > < by all right-thinking people. Whenever this tiny > < minority is kept from creating, or (as sometimes > < happens) is driven out of a society, the people > < then slip back into abject poverty. > < > < This is known as "bad luck". > < -Lazarus Long- > <------------------------------------------------------> http://www.aeroelectric.com ________________________________ Message 10 ____________________________________ Time: 05:00:30 PM PST US From: "Paul Messinger" Subject: Re: AeroElectric-List: So where's my award? --> AeroElectric-List message posted by: "Paul Messinger" Bob: You are correct I never told you "exactly" why the OVP was prone to tripping. I did repeatedly point out under what conditions it did (and at least once you agreed that my specific condition could cause false tripping) BUT you never seemed follow up on that tip. I showed the circuit to two other qualified electronic engineers and they both immediately saw several problems(the same ones I saw). I thus assumed you were not interested in my findings as below you continue repeat the "mantra" :-) of the past "sold thousands and neglable feedback". I have dozens of false tripping reports as does Eric and for the most part the builder simply throws the OVP away as for the cost of dealing with "infamous verbose hassle" you show the poster on the web its simply not worth it. Ever really wonder why with all the people who listen why so few post??? No mystery to many of us :-) You as the designer needs to prove its a good design NOT the other way around where the detractor must prove you wrong. Never heard of that (your) approach anywhere else but from you. MY total design experience is that, when the design is questioned, the designer must prove the questioner is wrong (assuming there is some semblance of credibility in the questioner and in my career that was always a given). It has been my experience that telling someone how to spot a design problem has large educational value in teaching how to design in the future, to detail the specific fix to the problem has little educational value. Thus I simply pointed out where to look and assumed that if you were interested you would follow up. In this case its not hard to see the problem(s) but so far not all the design issues (in the OVP) have been properly looked at and corrected. One source of false tripping has been defined but there is another to be corrected. Finally please do not lay back and think the OVP is now bug free. Far from it, it still has another design issue that causes false tripping as well as severe overstress in one part under reasonable application conditions. Worst case design is worst on worst case over part tolerance and temperature conditions (a max value and a min value some times produce the worst case so its not a simple all max or all min values that are really worst case conditions) and also the so called "RSS" is not worst case and while it is often used to get a marginal design to show its valid when its really not. A straight forward worst case circuit analysis using real bus voltage level transients (fast and slow) will immediately show another design short coming. In my case the patched design (my version) worked most of the time under DO-160 and failed all of the time under the harder to pass automotive design requirement conditions. My test conditions were nominal components under typical modern aircraft designs NOT some "wild worst case approach" to try to prove a design wrong. In fact I had no idea that the OVP had a design problem until I tried to use it in the Load Dump testing of 1 1/2 years ago. There it failed 100% of the time and so did a second unit. I was forced to find and fix the design. As I feel its not a good design approach I simply patched it and pressed on. I do not feel its my place to spend time trying to prove to you that the details are defective when the concept is defective in my opinion. IS a better design approach available YES. Is it more reliable YES. Does it eliminate the unintended side affects of the current design YES. So why do we continue to stick our head in the sand and refuse to use more modern technology? Beats me :-) I have never seen any worst case analysis on any of your designs. If I missed one please send me the link. I have been considering posting more details on this general subject and I may in the near future limited to the specific subject of OVP and internally regulated alternators as there are some industry wide truths (facts that is) that seem to be missing from posts on this list that directly contradict what is frequently posted as truths etc. Paul ----- Original Message ----- From: "Robert L. Nuckolls, III" Subject: Re: AeroElectric-List: So where's my award? > --> AeroElectric-List message posted by: "Robert L. Nuckolls, III" > > > What kind of "bonuses" are we talking about here? Mr. Lehman has > received nothing more than my enthusiastic appreciation for > illuminating > something I missed when offering a design up to my readers for > crafting a useful accessory to their electrical system. Paul > (and to some extent you too) have commented on the "tendency > to nuisance trip" for that circuit and have branded it unworthy > of consideration by the prudent designer. B&C and I have sold > thousands > of those systems with an exceeding low rate of difficulty so I > was mystified as to why your and/or Paul's experiences were so > unrewarding. I had no way of knowing how many folks had tried > the roll-yer-own but I DID receive what had to be a disproportionate > number of unhappy feedback. > > Ken's work showed us exactly WHY the circuit as offered from > my website is especially dv/dt vulnerable. It also prompted a > study on my part to discover the differences between what > we've sold and what numerous others have built. I would have > been just as enthusiastic if you or Paul would have caught > the design flaw and brought it to light. I have invited > you both repeatedly to participate in the discovery, explanation > and distribution of simple-ideas that help us move our craft > forward. > > I have a standing invitation on my website for anyone > to document any useful contribution for addition to the collective > pile. I don't have anything from you or Paul to post there yet > but I DO have something from Mr. Leyman. Ken's contribution > is quite simple but profoundly significant in solving a years-old > mystery concerning my implementation of the crowbar ov protection > philosophy. > ________________________________ Message 11 ____________________________________ Time: 08:39:20 PM PST US From: Dino Bortolin Subject: AeroElectric-List: Re: PTT coiled cord --> AeroElectric-List message posted by: Dino Bortolin I think every dollar store I've been in has replacement coiled phone cords for sale. Dino Bortolin 601XL/Corvair (0.1%) ________________________________ Message 12 ____________________________________ Time: 09:06:54 PM PST US From: "Robert L. Nuckolls, III" Subject: Re: AeroElectric-List: Re: PTT coiled cord --> AeroElectric-List message posted by: "Robert L. Nuckolls, III" At 11:37 PM 7/27/2005 -0400, you wrote: >--> AeroElectric-List message posted by: Dino Bortolin > > >I think every dollar store I've been in has >replacement coiled phone cords for sale. Not house telephone cords. Most if not all of these use copper "tinsel" conductors for extreme flexibility. The cords I'm suggesting are offered on cigar lighter adapters for cell phones. The two I've cut up had real wire inside that offered reasonable expectations of durable termination. The tinsel in telephone handset cords is VERY difficult to work with. Bob . . . ________________________________ Message 13 ____________________________________ Time: 10:58:19 PM PST US Subject: AeroElectric-List: Paul Messinger From: Gerry Holland --> AeroElectric-List message posted by: Gerry Holland I apologise up front to the group for being long winded. Paul Messinger Why have YOU not lived up to your commitment to the rest of the Group as quoted below from your dramatically delivered e-mail of April 23rd 2005. I Quote: I apologize to the group and I do not expect to ever post here again and I will ask that no one else forwards a press release of mine to this group. Why have you not taken your own advice as stated in YOUR e-mail of July 15th 2005. I quote: NO this not mean a return to posting but I will respond to what I feel are misstatements of my words. NO one has misstated your words. In this case you just jump on a bandwagon after Eric Jones e-mail regarding an award and snipe away and pontificate. Eric's comments although sometimes on the edge of rudeness for me are normally scattered with some respectful comments and his product knowledge has been turned into a product range that is always a good consideration or use. He is one of life's character and long may he remain. Whether you intend it or not, and allowing for the smallest mitigation of misinterpretation due to e-mail syntax your input to this group is nothing short of a whinging tirade of self importance. Quoting you again from 23rd April 2005 and using your verbal dexterity to amend words: I quote: What part of private do you not understand?? What part of committing to leave the Group do YOU not understand! Please give us your technical solution, turn it into a product and then expose it to the vagaries of use by hundreds of Home builders around the world with their own particular and varied levels of expertise. Eric is doing it, Bob is doing it and both know they are open to criticism and product failure. The vast amount of criticism and comment on this group is balanced and valid. Products do get modified to remove or improve points of failure. Yours is a tirade based on I dont agree because it isn't what I want or believe. You have a right to object, should be able to object but not as a series of guerrilla attacks on this Forum as and when you feel like hearing your own voice. Do me a favour at least please. Give us 24 hours email notice that you are building up for a sanctimonious outburst and I can adjust my spam filter to remove the inevitable following tirade from you. Paul. Either keep quiet as you keep threatening or build us this perfect product you have in your mind based on the often quoted experience you have and put in on the market. Again. My apologies to the rest of the group for my obvious irritated outburst. Regards Gerry How much free photo storage do you get? Store your holiday ________________________________ Message 14 ____________________________________ Time: 11:39:35 PM PST US From: "Robert L. Nuckolls, III" Subject: Re: AeroElectric-List: So where's my award? --> AeroElectric-List message posted by: "Robert L. Nuckolls, III" At 04:58 PM 7/27/2005 -0700, you wrote: >--> AeroElectric-List message posted by: "Paul Messinger" > >Bob: You are correct I never told you "exactly" why the OVP was prone to >tripping. I did repeatedly point out under what conditions it did (and at >least once you agreed that my specific condition could cause false tripping) >BUT you never seemed follow up on that tip. That's cheesy Paul. Look at all the work I did in response to your salvos of cabbages and all you have to offer now is that I "seemed uninterested" in following up on a TIP? If you KNEW, why keep it a secret? >I showed the circuit to two other qualified electronic engineers and they >both immediately saw several problems(the same ones I saw). If they KNEW, why keep it a secret? >I thus assumed you were not interested in my findings as below you continue >repeat the "mantra" :-) of the past "sold thousands and neglable feedback". That "mantra" was data based on experience. Do you belive I was lying to you? If you're accusing me of dishonorable behavior, then we have nothing more to discuss. Delete this message but do drop me a note that describes your true beliefs. >I have dozens of false tripping reports as does Eric and for the most part >the builder simply throws the OVP away as for the cost of dealing with >"infamous verbose hassle" you show the poster on the web its simply not >worth it. I have never chased off anyone who was having a problem with one of my products. At the minimum, he/she can expect to get their money back no questions asked. How is it that YOU TWO know of all these disgruntled customers but they never bothered to contact me? I don't buy it. I offered to give cash refunds + nuisance bonus to anyone you knew that had a problem with a product I supplied if they would simply tell me of their personal experiences. How can I gather field data if everyone claiming that my "mantra" is just marketing propaganda but at the same time, is unwilling to help me identify and fix real problems. It's equally mystifying that these same individuals ARE willing to add his/her name to the growing list of Bob'a unhappy customers maintained by Eric and Paul. That's bull hockey sir. >Ever really wonder why with all the people who listen why so few >post??? No mystery to many of us :-) >You as the designer needs to prove its a good design NOT the other way >around where the detractor must prove you wrong. Sorry sir but that miserable bucket just doesn't hold water. If the folks I work with at my day job had your attitude with respect to the engineering profession, we'd have crashed and burned years ago. How many times have I extolled the virtues of good critical design review? When you're a customer oriented supplier of goods and services, we help each other out . . . not stand off and toss tomatoes and cabbages at each other. >Never heard of that (your) approach anywhere else but from you. MY total >design experience is that, when the design is questioned, the designer must >prove the questioner is wrong (assuming there is some semblance of >credibility in the questioner and in my career that was always a given). I went off and researched every incoming cabbage and tomato you pitched when you started claiming 700A faults and breakers that would go belly up at interrupts more than 10x rated trip current. I started a white paper to demonstrate fault currents very benign compared to your claimed "killer cabbages". When I produced feedback from Eaton/Cutler-Hammer, Klixon, and a stack of spec documents that debunked your claim about breakers, you countered with, "Well, the breakers I was using won't tolerate that abuse and I've got golden specs to prove it." I asked you for brand and part number of any breaker that was so limited but I've yet to see any such spec. After the effort to field your cabbages without learning anything useful, I didn't have the energy to address any "hints" you might have made on the circuitry. Besides, after 10+ hours of work proved two of your salvos to be hogwash, I was hard pressed to assign any credibility to any other claims you might have made . . . especially when unaccompanied by supporting simple-ideas . . . only cabbages. >It has been my experience that telling someone how to spot a design problem >has large educational value in teaching how to design in the future, to >detail the specific fix to the problem has little educational value. Thus I >simply pointed out where to look and assumed that if you were interested you >would follow up. In this case its not hard to see the problem(s) but so far >not all the design issues (in the OVP) have been properly looked at and >corrected. One source of false tripping has been defined but there is >another to be corrected. Boy, am I glad I never had any teachers with your teaching style. Besides, which was more important (1) teach that ol' fart in Wichita how to design or (2) expose the details of a problem that was being repeated many times over by readers of my work? I'm beginning to belive you're more interested in whacking me than in helping folks on this List. It appears that the more poor saps who built the circuit as-published and had problems with it, the happier you are. You seem to have collected quite a list of names for which only you are aware. >Finally please do not lay back and think the OVP is now bug free. Far from >it, it still has another design issue that causes false tripping as well as >severe overstress in one part under reasonable application conditions. Worst >case design is worst on worst case over part tolerance and temperature >conditions (a max value and a min value some times produce the worst case so >its not a simple all max or all min values that are really worst case >conditions) and also the so called "RSS" is not worst case and while it is >often used to get a marginal design to show its valid when its really not. I assume nothing. I'm still waiting for data but I quit holding my breath months ago . . . >A straight forward worst case circuit analysis using real bus voltage level >transients (fast and slow) will immediately show another design short >coming. In my case the patched design (my version) worked most of the time >under DO-160 and failed all of the time under the harder to pass automotive >design requirement conditions. My test conditions were nominal components >under typical modern aircraft designs NOT some "wild worst case approach" to >try to prove a design wrong. In fact I had no idea that the OVP had a design >problem until I tried to use it in the Load Dump testing of 1 1/2 years ago. >There it failed 100% of the time and so did a second unit. I was forced to >find and fix the design. As I feel its not a good design approach I simply >patched it and pressed on. I do not feel its my place to spend time trying >to prove to you that the details are defective when the concept is defective >in my opinion. >IS a better design approach available YES. Is it more reliable YES. Does it >eliminate the unintended side affects of the current design YES. So why do >we continue to stick our head in the sand and refuse to use more modern >technology? Beats me :-) Who is refusing anything? I wrote just a few weeks ago that I welcome anything new and better. The only thing you've offered so far is a demonization of my field proven products and zero suggestions of anything different or better. How many happy customers are flying your designs sir? I agree that applying OVP protection to the internally regulated alternator wasn't well conceived . . . that wasn't a fault of the crowbar ov protection system but a lack of capability in the style of contactor selected -AND- a lack of confidence with respect to characteristics of the constellation of designs. The same basic problems persist IRRESPECTIVE of how you chose to sense and react to the OV event. The "thousands of happy customers" I've referred to are all flying aircraft alternators. Yes, there is work to be done with respect to the internally regulated alternator and I thought that's what you an Eric were offering to help with when this discussion was started over a year ago. But instead of a collaborative effort utilizing data I thought you were going to acquire, I've wasted a lot of time fielding tossed cabbages . . . and we've yet to see any data. >I have never seen any worst case analysis on any of your designs. If I >missed one please send me the link. > >I have been considering posting more details on this general subject and I >may in the near future limited to the specific subject of OVP and internally >regulated alternators as there are some industry wide truths . . . Give us links to your "industry wide truths" . . . >. . . (facts that is) >that seem to be missing from posts on this list that directly contradict >what is frequently posted as truths etc. When Ken revealed his discovery earlier this week the light bulb went on. "Gee, that's what's causing problems for Paul and several others with the DIY circuit." The effect turns out to be unique to the DIY circuit as published and not relevant to the thousands of products we've fielded over the years. So while I was offering the only DATA I had based on experience with the marketplace, you were holding SECRETS close to the chest to the torment of myself and others who had also built the DIY circuit. For years, the tag line on my e-mail signature was //// (o o) ===========o00o=(_)=o00o========= < Go ahead, make my day . . . > < show me where I'm wrong. > ================================= This wasn't a joke. It's still applicable. When we had an issue come up with the crowbar system in Bonanzas, we jumped on it and got it fixed in jig time because we had the cooperation of everyone who was concentrating on the CUSTOMER. The benefits of that discovery were incorporated across the product line. Well, readers of this list are my customers, who are yours? I'm through proving anything to you Paul. I'm just worn out. If you want to make a contribution to this discussion, do it with schematics, bills of materials, maufacturer's data sheets and repeatable experiments that I or ANYONE here on the list can duplicate, evaluate and exploit. Help me take care of the customers and quit wasting my time. The offer still stands. Give us some simple-ideas worthy of induction into the AeroElectric Hall of Fame (while sticking it to Bob). Let the List decide. You give them something they say addresses the issues of my offer (doesn't even mention OV protection) and my check will be in the mail the same day. Let's figure out why George blew up his Transorbs. Let's see if Transorbs alone can be reasonably expected to mitigate load dump and/or ov effects for every style of alternator a builder might pull off a car. Let's see if there are reasonable approaches to regulator design that will mitigate if not eliminate the effects of a load-dump event. You'd better not wait too long. I've got a 2 h.p. variable speed drive and some other goodies that will eventually be assembled into a test stand for proving a whole new line of processor based electrical system management products. However, if I'm forced to answer all the questions I've posed without your help, then the results will be published here on the List. After that, the only way I'm going to let you "stick it to Bob" is to "make my day and show me where I'm wrong." I am mystified as to how you can KNOW the specifics of a design error, allow the numbers of victims to grow because of your silence, compile secret lists of victims of the error as manifest evidence of the incompetence of the designer, and then claim to be helping the designer grow in stature by offering "hints" of your secret buried in a avalanche of unsupported allegations. You'd think I was seeking confirmation to the Supreme Court or something. Ken has let at least one of your secrets out of the bag. It's well on the way to being corrected and I've made my thanks for his participation in good critical review well known. His contribution to this discussion far outweighs anything I've seen from you sir. The only appreciation I can muster for our conversation thus far are the benefits of having reviewed a lot of specs that supported what I've understood for the past 20+ years. Bob . . .