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JC <Chipbee40_SpamNo@yahoo.com>: Jul 17 07:27PM -0400 So, hoped to have left all this mechanical error measurement stuff behind me back in the 80's but I guess with the renewed interest in vinyl its all coming out of the woodwork. Leader LFM=3610 W&F meter, customer wants it calibrated or at least verified. don't have schematics or full cal manual. Manual I do have suggests use of Leader LFM-7000 W&F calibrator, don't have that either.   So........ How can I reproduce some of the cal signals, for example JIS, 1%, 4Hz modulation at 1vrms?   JIS is 3KHz sine, so no problem, but how to add the 4Hz modulation? FM obviously, (AM would be easy), but how? Can't be a 4Hz sweep on 3Khz, can't be a 4Hz burst? Superimposed 4Hz on 3Khz? How to quantify 1%?   I have a wide range of hardware and software signal gens available but no idea how to mimic this accurately.   Any of you audio guys have digital waveforms/ test cd's handy you can share? Help! TIA

Clifford Heath <no.spam@please.net>: Jul 18 11:35AM +1000 On 18/07/16 09:27, JC wrote: > can't be a 4Hz burst? Superimposed 4Hz on 3Khz? How to quantify 1%?   > I have a wide range of hardware and software signal gens available but > no idea how to mimic this accurately.   AD9851 module and an Arduino? It probably wouldn't even be necessary to calibrate the primary crystal source, or switch to a TCXO.

Phil Allison <pallison49@gmail.com>: Jul 17 08:08PM -0700 JC wrote:   > JIS is 3KHz sine, so no problem, but how to add the 4Hz modulation? FM > obviously, (AM would be easy), but how? Can't be a 4Hz sweep on 3Khz, > can't be a 4Hz burst? Superimposed 4Hz on 3Khz? How to quantify 1%?   ** 1% is the frequency deviation, 4Hz is the rate.   So +/- 30Hz deviation four times a second.   ( The ear is most sensitive to a 4Hz rate)     > I have a wide range of hardware and software signal gens available but > no idea how to mimic this accurately.   ** Some function generators have an external modulation input.   Set the generator to 3kHz and use a small DC input to get 3030 Hz.   A 4Hz sine wave with the same peak value is then required.       ... Phil

Black Iccy <Daedelus@whereamIinvalid.com>: Jul 18 02:10PM +1000 >Any of you audio guys have digital waveforms/ test cd's handy you can >share? Help! >TIA   Phil just clarified your requirements. You can generate a waveform tone via Adobe Audition (Ver 3 or earlier) assuming you can find a copy (Win). Save as Wav or whatever.   Base Mod by Mod freq (rate) 3Khz +/- 'x'Hz @ rate 'y' 3000 30 4

DaveC <not@home.cow>: Jul 17 01:13PM -0700 http://imgur.com/a/6qeua   (The images of the plug are stills from a video. I don't have it in my possession.)   The header measures approx.: pin dia: 0.6 mm,0.024 in spacing: 3.85 mm, 0.152 in     How can I identify the type of shell and pin used in this connector?   Thanks.

axolotyl <axolotyl@axolotyl.com>: Jul 18 11:51AM +0800 On 18-Jul-16 4:13 AM, DaveC wrote:   > How can I identify the type of shell and pin used in this connector?   > Thanks.   Could it be 3.81mm / 0.150" pitch?   mouser 87221- TE Connectivity / AMP Connectors http://au.mouser.com/Search/Refine.aspx?Keyword=87221-

"Danny D." <dannydiamico@yahoo.com>: Jul 12 12:23AM On Tue, 12 Jul 2016 00:08:49 -0000 (UTC), Danny D. wrote:   > One problem is that I can't tell what's going on from the sound, but when I > hooked all the old parts back, it kicked off again as it did when I started > this thread.   The main problem I have is that I don't know what a good compressor humming sounds like, compared to a bad compressor humming.   Is it safe to leave the test jig in place for an hour or three to see if the lines get cold?

"tom" <tmiller11147@verizon.net>: Jul 11 08:33PM -0400 "Danny D." <dannydiamico@yahoo.com> wrote in message news:nm1d9e$bgh$1@news.mixmin.net... > sounds like, compared to a bad compressor humming.   > Is it safe to leave the test jig in place for an hour or three to see if > the lines get cold?   If the compressor is running, the discharge line (the smaller copper tube) will get warm (hot).

"Danny D." <dannydiamico@yahoo.com>: Jul 12 12:28AM On Mon, 11 Jul 2016 20:06:03 -0400, tom wrote:   > Just for the hell of it can you take an ohmmeter measurement from any of the > three terminals to the case? It should show open (very high resistance). If > it measures any resistance, the compressor is bad.   Thanks for that advice, as I'm at a loss as to how to know the humming sounds of a good versus bad compressor.   I did check the resistance when I was trying to figure the pinout of the compressor three pins, and all are insulated.   But thank you for that idea as I had not mentioned that test.

"Danny D." <dannydiamico@yahoo.com>: Jul 11 10:13PM On Mon, 11 Jul 2016 15:02:16 -0700 (PDT), Uncle Monster wrote:   > A 12uf 5,000 volt capacitor charged up could hurt you. ^_^   The markings on this cap are: http://i.cubeupload.com/QBVskg.jpg 1. 12uF 2. 180VAC (it was charged to 120VAC) 3. 10,000AFC (I presume this is cycles?) 4. 50/60Hz   Can that 120VAC 12uF zap kill me? Is it safe (to the cap) to short the terminals?

Bob Engelhardt <BobEngelhardt@comcast.net>: Jul 12 11:46AM -0400 On 7/12/2016 10:59 AM, Danny D. wrote: ... > Is the inlet on the right and the outlet on the left in this picture? > http://i.cubeupload.com/9ZZ7fw.jpg   I can't help you there. Tom? > C. START to RUN = slightly less than 10 ohms   > Given all that, I tentatively assume that the motor is working fine > electrically; but that mechanically, it seems to be locked up.   That sounds right.   > However, I would have expected 17.6 Amps if the motor were locked up, so, > I'm curious why I get 12 Amps instead - but maybe that's because it never > started?   If the motor isn't starting, that is "locked rotor". That it's 12A & not 17.6 is not particularly useful. 12A is still way more than running current. That's 1440 watts & I'd guess the operating power to be 400W (4A), maybe, probably less. 400W is about 1/3hp, which seems like a lot for a fridge.   Bob

Stormin Mormon <cayoung61@hotmail.com>: Jul 12 10:53PM -0400 On 7/12/2016 10:47 PM, Danny D. wrote: >> my hints and reminders.   > You mean this? > http://i.cubeupload.com/VD0haS.jpg   I added a g to the end of the URL, and got a picture. I can't comment on that, until you answer my question. -- . Christopher A. Young learn more about Jesus . www.lds.org . .

"Danny D." <dannydiamico@yahoo.com>: Jul 13 02:46AM On Tue, 12 Jul 2016 18:33:27 -0400, Stormin Mormon wrote:   > After the inspection, weld the compressor using a gas tight "bead" of weld. > Replace the refrigerant.   > No problem for you, right?   :)

Stormin Mormon <cayoung61@hotmail.com>: Jul 12 10:51PM -0400 On 7/12/2016 10:47 PM, Danny D. wrote: >> my hints and reminders.   > You mean this? > http://i.cubeupload.com/VD0haS.jp   "not found" is what the web page says.   -- . Christopher A. Young learn more about Jesus . www.lds.org . .

"tom" <tmiller11147@verizon.net>: Jul 12 05:26PM -0400 "Danny D." <dannydiamico@yahoo.com> wrote in message news:nm3jg9$d0q$1@news.mixmin.net... > tools for $100, where the tool either fixes the problem or the tool tells > me exactly what that problem is.   > But, in this case, I don't think there is that $100 tool option, is there?   Apart from this problem, a good Fluke DMM would be on my immediate acquire list. And never loan it out if you want to be able to trust it.   There are "hard start" compressor starters available that might be worth looking at.   Can you take some more pictures of the start relay? From different angles?

Jon Elson <jmelson@wustl.edu>: Jul 12 05:23PM -0500 Danny D. wrote:     > While the capacitor has been tested, I understand what you're saying, > which is to pay a bit less than $100 to replace the cap and starter, > essentially throwing parts at the problem.   You should be able to get a replacement start cap for MUCH less than $100, and just bypass the starting relay. You will hear instantly if the compressor starts. If it does, the compressor is OK, and the only piece left is the relay. Some time ago I got a run cap from a refrigeration supply for $6. I expected it to be more.   And, if the compressor does not start with the new cap and the relay bypassed, then you can be fairly sure the compressor cannot be salvaged.   Jon

"Danny D." <dannydiamico@yahoo.com>: Jul 17 09:18PM On Fri, 8 Jul 2016 23:22:01 -0000 (UTC), Danny D. wrote:   > Debugging advice requested.   I ran out of options. I can't think of anything else to do to debug.   One of the rare times in my life where I lost the battle to even *diagnose* something, let alone fix it.

Stormin Mormon <cayoung61@hotmail.com>: Jul 17 06:28PM -0400 On 7/17/2016 5:18 PM, Danny D. wrote: > I can't think of anything else to do to debug.   > One of the rare times in my life where I lost the battle to even *diagnose* > something, let alone fix it.   You might (simply) answer Stormy's simple question. I have a bit of a guess what is going on.   -- . Christopher A. Young learn more about Jesus . www.lds.org . .

"Danny D." <dannydiamico@yahoo.com>: Jul 17 11:33PM On Sun, 17 Jul 2016 18:28:30 -0400, Stormin Mormon wrote:   > You might (simply) answer Stormy's > simple question. I have a bit of a > guess what is going on.   I have no idea *what question* you are asking. In response to *this* post, would you kindly just ask the question? Is it the polygamy question?

Stormin Mormon <cayoung61@hotmail.com>: Jul 17 08:14PM -0400 On 7/17/2016 7:33 PM, Danny D. wrote:   > I have no idea *what question* you are asking. > In response to *this* post, would you kindly just ask the question? > Is it the polygamy question?   I asked it two or three times. I repeated, changed the subject line to indicate there is a question. You quoted it, my very simple question (at least) three times in your twenty post rehash. I've kindly asked, reminded, reposted, encouraged, others have highlighted the question, and no I'm not going to do your job for you.   BTW, the simple answer should be five words or less. I can answer it in three.   -- . Christopher A. Young learn more about Jesus . www.lds.org . .

"Danny D." <dannydiamico@yahoo.com>: Jul 18 12:47AM On Sun, 17 Jul 2016 20:14:36 -0400, Stormin Mormon wrote:   > going to do your job for you.   > BTW, the simple answer should be five words > or less. I can answer it in three.   1. The 2. Warranty 3. Expired ----- 4. Long 5. Ago

Jeff Liebermann <jeffl@cruzio.com>: Jul 16 07:45PM -0700 On Sat, 16 Jul 2016 16:03:11 -0000 (UTC), Cursitor Doom >and the cap probably partially discharged through it. >So the 10 shilling postal order and box of After Eight mints goes to.... >Jeff Liebermann! :-)   The logic was easy. You had already done most of the obvious troubleshooting (increase load, add capacitors, check currents). There was only one active device capable of causing a problem. All that was necessary was to contrive a reasonable explanation and failure mechanism. The near maximum voltage was an obvious problem and blowing it up by shorting the input or output to ground was quite likely. As Sherlock Holmes may have said: Once you eliminate the impossible, ridiculous, absurd, and disgusting, whatever remains, no matter how improbable, must be what's wrong.   Thanks, but no gratuities needed. Besides, the body mechanic says that I shouldn't eat chocolate. Sigh.   -- Jeff Liebermann jeffl@cruzio.com 150 Felker St #D http://www.LearnByDestroying.com Santa Cruz CA 95060 http://802.11junk.com Skype: JeffLiebermann AE6KS 831-336-2558

Cursitor Doom <curd@notformail.com>: Jul 17 11:27AM On Sat, 16 Jul 2016 19:45:41 -0700, Jeff Liebermann wrote:   > The logic was easy. You had already done most of the obvious > troubleshooting (increase load, add capacitors, check currents). There > was only one active device capable of causing a problem.   False assumptions have always plagued me. In this instance I falsely assumpted that because the reg was functioning fine under a heavy passive load, there was nothing whatsoever wrong with it. I didn't admit to the possibility of partial damage which could manifest under other load conditions and that made me completely blind to fixing the problem. Lesson learned - I hope!

Jeff Liebermann <jeffl@cruzio.com>: Jul 17 08:34AM -0700 On Sun, 17 Jul 2016 11:27:18 -0000 (UTC), Cursitor Doom >possibility of partial damage which could manifest under other load >conditions and that made me completely blind to fixing the problem. >Lesson learned - I hope!   Assumption is the mother of all screwups. If it helps, I think everyone has the same problems with bad assumptions. It's our way of simplifying our lives. Our brains are pre-programmed to look for patterns and repetitions, so we generalize based on the available but usually insufficient evidence. Don't fight it. Assumption and generalization work well if properly used.   In my life, I've noticed that first impressions are usually correct. That applies mostly to people, but also to things. I just look at the circuit, the components, the PCB, or the schematic, and ask myself "what's the most likely culprit". Never mind logic, deduction, measurement, and flow charts. Just intuition based on experience. For example, I always look for bulging capacitors, previous repairs, crappy soldering, corrosion, bad wire connections, loose parts, signs of overheating, loose screws, and an assortment of common problems that can be found by inspection. Do it often enough, and it becomes automatic[1].   We have one big advantage with repair. We can assume that the circuit was designed correctly and that it did work at one time. All we need to do is find the one part that died. However, this was not really a repair task, but rather a construction or engineering task, which cannot make the assumption that the circuit was previously working. So, I ask myself, what is the most likely screwup someone could do and what were the likely causes of the circuit behavior? The behavior made no sense, so went through my history of all the things I've destroyed on the bench. I started with improper construction and ended with the effects of overvoltage and overload while looked for a pattern. Overvoltage and temporary wiring errors are my big problems. Often, the combination blows things up.   If intuition doesn't pay off, I make measurements. I suggested that you use a scope to look for oscillation and current spikes. It would have helped identify the exact symptoms, but would not have pointed directly to the LM317T.   I could go on forever on how I do troubleshooting. However much of it is more intuitive than logical. That's guaranteed to produce more confusion than enlightenment, so go with your first guess. It's usually right.   Good luck.     [1] I've been looking at resistor color codes for much of my life. I don't look at the colors individually and decode them into numbers and multipliers. I look at the entire resistor, automatically recognize the pattern, and (for example) 10K pops into my head. The same can be done with defective PCB's and products. Something that looks "odd" is often the culprit.   -- Jeff Liebermann jeffl@cruzio.com 150 Felker St #D http://www.LearnByDestroying.com Santa Cruz CA 95060 http://802.11junk.com Skype: JeffLiebermann AE6KS 831-336-2558

Cursitor Doom <curd@notformail.com>: Jul 17 06:48PM On Sun, 17 Jul 2016 08:34:01 -0700, Jeff Liebermann wrote: > repetitions, so we generalize based on the available but usually > insufficient evidence. Don't fight it. Assumption and generalization > work well if properly used.   I wouldn't have minded so much, but a while ago we had a thread on the golden rules of troubleshooting and my contribution was, of all things, "assume nothing" (!)   > is more intuitive than logical. That's guaranteed to produce more > confusion than enlightenment, so go with your first guess. It's usually > right.   So it's more of an art than a science? I'm not a professional technician so I don't do these sort of things on a daily basis. Consequently my reasoning skills are nowhere near as strong and well-developed as someone who's fully immersed in the business.

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