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John-Del <ohger1s@gmail.com>: Jul 23 07:35AM -0700 It had water damage. Screeching, squawking, full volume with the vol at zero, or no sound at all. I had to remove several connectors and other parts to wash the board in a parts washer (my sink). After reassembly, it works fine except the FM is low volume on both channels. AM is normal volume as are the other inputs. I think there's a problem around the function select IC (if not the IC itself).   I'm going to see if the customer uses the FM. If so, I'll have to do this backwards using datasheets. A schematic is almost like cheating... :)

etpm@whidbey.com: Jul 20 03:31PM -0700 >>"I am still a little amazed by the large value caps though. >Eric "   >Me too. Just now many HP is that thing ? Three HP.

etpm@whidbey.com: Jul 20 01:08PM -0700 >So, I stand corrected.   >In a condensing unit it won't start when there's backpressure, it'll kick out on overload a few times until the pressure bleeds off. In fact some newer electronic thermostats have a delay so it won't even try to start right away say if it just turned off and you reset the temperature, it will wait a few minutes. An AIR compressor now, well I can see my mistake. If you have it set to 100 PSI it will start with over 90 PSI loading it so a cap run type motor won't cut it.   >Glad you got it figured out. The compressor has an unloader so that there is no pressure in the cylinders when it first starts spinning. But of course as you said as soon as it delivers air into the receiver it is pushing air into 90 PSI. I am still a little amazed by the large value caps though. Eric

etpm@whidbey.com: Jul 18 08:20AM -0700 My compressor wouldn't start this morning. So I figured it might be a bad starting cap. But both caps had blown. All the guts right out of the ends. Could it be that one cap blew first and then the other cap failed because of the extra work it had to do? Thanks, Eric

etpm@whidbey.com: Jul 18 05:20PM -0700 >Are you sure they're start caps ? Some 3 phase motors can be run with a cap connected the right way, those are run caps. What I have seen is they are usually rated double the input voltage, like if it is 220 the caps are 440.   >Per your other thread, if they were 115 volts and in series you had like 200 uF, not ridiculous. High, but plausible. Even then the voltage rating is not high enough. If in parallel then you had like 1,000 uF which is very high, is this like a 5 HP or something ? In any case a 115 V cap will not take the voltage. In my other post I corrected myself. The caps were wired in parallel. So the total capacitance is around 1000 MFD. Just for fun I tried a 200 MFD cap and it would not start the motor. The motor would just barely start rotating but I could tell it wasn't gonna come up to speed before something got too hot. What happens if the capacitance is too high? I think the phase will just get shifted too much which may cause hard starting. On the other hand I seem to remember that the starting cap doesn't just help with phase shift it also provides extra energy for starting so maybe extra capacitance isn't all that bad. I don't remember but would like to know. Eric

etpm@whidbey.com: Jul 19 08:43AM -0700 On Wed, 18 Jul 2018 19:36:47 -0700, Jeff Liebermann <jeffl@cruzio.com> wrote:   >More: ><https://www.google.com/search?q=calculate+motor+starting+capacitor>   >I couldn't find anything on calculating the run capacitor. The model number is 90653-N. The motor has only two wires coming out to connect to the caps, so there is no starting cap. I tried a known good cap that is about 200 MFD and it won't start the motor. The motor tries to turn and I bet if I took the belts off it would start spinning. The motor does spin easily enough but with the compressor load it takes so long to spin up with the 200 MFD cap I'm afraid the motor will overheat or the breaker will pop and so I turned it off after a few seconds. The compressor is a two stage air compressor that came with the motor as a set. The compressor is unloading properly so the motor is not trying to spin up a huge load and the motor has been spinning the compressor just fine for the last 40 or 50 years. I find it odd that there is no running cap but there just plain aren't connections for one. Eric

Jeff Liebermann <jeffl@cruzio.com>: Jul 19 04:34PM -0700 >found that exact motor and he too was surprised that it did not not >have a run cap. The power factor of the motor, according to the label, >is 1.15. Wouldn't a run cap improve that a bit?   Yep. That's the purpose of the run capacitor. Start on Page 19: <https://www.scribd.com/document/6883830/Tutorial-Motor-Basics-Lecture> The way it works is when stopped both the start and run caps are in parallel. When the motor gets up to speed, a centrifugal switch opens and disconnects the start cap leaving the run cap in the circuit. That means if you try to add a run cap, you'll need to decrease the value of the start cap by the same amount. Since you're already have too high a capacitance on the two parallel start caps, this will mean that you'll be replacing at least one of the two new capacitors. >flywheel the pulsing torque from a single phase motor without a run >cap was not considered a problem because the flywheel would smooth >things out.   My guess(tm) is the start winding was intentionally undersized (which is why the start cap is so large). Exactly why, I don't know.   >right? I ask because I was told that if a smaller and larger value cap >are connected in parallel the lower value cap will work harder and so >fail sooner.   Nope. Two caps in parallel will distribute the current going through them by the ratio of the capacitive reactance (Xl - 1/(2Pi*f*c). The larger capacitor will have the smaller series reactance and therefore draw the most current. However, in the motor, we have a resonant situation, where the run capacitor has a capacitive reactance equal to the inductive reactance of the motor run winding, and therefore cancel each other leaving just the winding resistance to dissipate any power. That's also the ideal power factor point. So, if you parallel a mess of capacitors to make a run capacitor with the correct value for PF=1, then the capacitors will dissipate zero power.   >documentation on the compressor. I think that's pretty good service. >Especially since Grainger wasn't gonna be able to sell me new parts to >fix the compressor.   Impressive but what will they do when the warehouse guy retires?     -- 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

Jeff Liebermann <jeffl@cruzio.com>: Jul 19 04:48PM -0700 On Thu, 19 Jul 2018 16:34:42 -0700, Jeff Liebermann <jeffl@cruzio.com> wrote: >>things out.   >My guess(tm) is the start winding was intentionally undersized (which >is why the start cap is so large). Exactly why, I don't know.   Ok, I'm wrong. That's not the reason and nothing is wrong. <https://www.scribd.com/document/6883830/Tutorial-Motor-Basics-Lecture> See the drawing on Pg 20 of a capacitor start motor (as opposed to a capacitor start and capacitor run motor). It has only a starting capacitor and no run capacitor. According to the accompanying text: - Larger single phase motors with up to about 10 HP. - A split phase motor with the addition of a capacitor in the starting winding. - Capacitor sized for high starting torque. - Very high starting torque - Very high starting current - Common on compressors and other hard starting equipment.   So, adding a run capacitor isn't going to do anything useful with this type of motor. Sorry for the bad guess(tm) but I'm not familiar with this type of motor. Everything I've seen has both capacitors.           -- 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

etpm@whidbey.com: Jul 19 09:14AM -0700 On Wed, 18 Jul 2018 19:36:47 -0700, Jeff Liebermann <jeffl@cruzio.com> wrote:   >More: ><https://www.google.com/search?q=calculate+motor+starting+capacitor>   >I couldn't find anything on calculating the run capacitor. Looking again I see that there are TWO model numbers on the motor nameplate. The top one is 5K483-D, which is a good number as I found it on the Grianger website. The other model number is on the bottom of the ID plate and it says Motor Model Number whereas the top model number just says Model. I have never seen this before. Anyway, I called Grainger because the cap(s) weren't listed. The guy at Grainger had to pull a file but he did find the caps and there are two. Both caps are 485-582 MFD and are wired in parallel. They are both start caps and the motor has no run cap. I have two cap coming tomorrow but they are 540-685 MFD. Will them maybe be a problem? In the meantime I will try to get the proper caps. Thanks, Eric

N_Cook <diverse@tcp.co.uk>: Jul 23 11:03AM +0100 Googling getting no where. The context may be old aircraft cockpit or for training of morse code, reportedly. A dovetail-cornered purpose made wooden boxed set of spare, probably keycaps , not-transparent , black bakelite with white pantograph inscribed and whited for visibility. Each cap is individually inscribed with numbers like 5C/1214 and the boxed set is labelled REF. No 5C/2210 (the o of No is lower case but raised with a bar under American military abbreviation?). Each letter keycap is oriented differently and with a unique set of flutes for very specific registration. But the real mystery is the box has 24 recesses for 24 keycaps , A to Z, but with E and T missing, so 24 not 26 letter alphabet.

Andy Burns <usenet@andyburns.uk>: Jul 23 11:40AM +0100 N_Cook wrote:   > REF. No > (the o of No is lower case but raised with a bar under American military > abbreviation?).   The numero symbol № is pretty standard (maybe a little old-hat)   <https://en.wikipedia.org/wiki/Numero_sign>

mike <ham789@netzero.net>: Jul 22 04:34PM -0700 > the tiny lense, which probably would come off with some > windex on a q tip. Was just wondering if that is ok or would alcohol be > harmful to the lense? "little bit" is inadequate description. If that's the IR filter, removing it would be ill-advised.

Jeff Liebermann <jeffl@cruzio.com>: Jul 22 08:37PM -0700 >several tiny smd caps mounted around the perimiter. At first they >looked like some kind of edge guide...had to go to extreme mag to even see >the detail.   Look at the dissembly photos in iFixit for how to put it back together. <https://www.ifixit.com/Device/iPod_Touch_6th_Generation> <https://www.ifixit.com/Teardown/iPod+Touch+6th+Generation+Teardown/44378> I can't tell what the thing above the lens does. Offhand, it looks like a connector, not a UV filter, but I'm not sure.   This is what the rear facing camera looks like: <https://globaldirectparts.com/oem-apple-ipod-touch-6th-generation-rear-facing-camera/> and this is the front: <https://www.ebay.com/itm/OEM-Front-Facing-Camera-MODULE-Parts-Repair-Replacement-For-iPod-Touch-6-6th-Gen/142878230953>   Good luck on removing the glue. Next time you do this, try hot melt glue or something that can be easily removed.   -- 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

nckeyman@gmail.com: Jul 22 02:18PM -0700 I have same game cabinet.. I'm aware this was first created in 2010.. I turn on the switch and the monitor shows some colors vertically and then a bright dot about 6 inches across and that's it.. any suggestions

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