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harry newton <harry@is.invalid>: Dec 04 01:14PM I haven't worked on speakers in decades. <http://wetakepic.com/images/2017/12/04/speakers1.jpg>   How do we debug a scratchy sound? We can isolate it with the balance to a single speaker.   But is it the speaker? Or something else?   If it's the speaker, where is a good place (other than the dealer) to get speakers to fit a car rear deck? Are they all standard sizes nowadays? Or is each unique?   I'm helping the neighbor's kid refurbish a beat-up 2005 Camry where I helped her kid put in new speaker covers this weekend but the scratch sound persisted (we thought it might have been the crud or vibration from the crumbling melted-in covers).   The scratchy sound persisted even with the newly replaced covers. <http://wetakepic.com/images/2017/12/04/speakers2.jpg>   Any suggestion on how to debug the cause of the scratchiness? If it's the speakers themselves, are these things standard sizes nowadays?

"pfjw@aol.com" <pfjw@aol.com>: Dec 04 05:48AM -0800 Could be so many things from a dead bug in the voice-coil to a blown speaker to any of a dozen other causes. If you can feed the speaker from another source and if *does not* scratch, you have a problem with the head-end (electronics). If it continues to buzz, it is the speaker. Before replacing it, try removing it from the vehicle and blowing it out with canned air (NOT compressed air - far too powerful), paying attention to the voice coil below the spider. If crud gets in there, that will cause the buzz. Also gently press the cone in - do you feel any scraping? If so, the speaker is done.   Parts Express will sell you speakers in many configurations, sizes and styles. Something will fit. Keep in mind this is a Camry. Which is a not-particularly sound-proof device, and within which speakers are more noisemakers than high-fidelity audio reproducers. What you will need to do is pay attention to polarity when you install the new speaker.   Good luck with it.   Peter Wieck Melrose Park, PA

kludge@panix.com (Scott Dorsey): Dec 04 09:34AM -0500 >We can isolate it with the balance to a single speaker.   >But is it the speaker? >Or something else?   You can swap the speaker for the one from the other side. But "scratchy" sounds are apt to be rubbing voice coils which you can feel by pressing on the cone with your thumbs.   >If it's the speaker, where is a good place (other than the dealer) to get >speakers to fit a car rear deck? Are they all standard sizes nowadays? Or >is each unique?   There are several standard sizes. You can buy cheap replacement speakers from chain auto parts stores. You can buy the same speakers for half as much from Parts Express but then pay postage on them. --scott -- "C'est un Nagra. C'est suisse, et tres, tres precis."

micky <NONONOmisc07@bigfoot.com>: Dec 04 11:35AM -0500 In alt.home.repair, on Mon, 4 Dec 2017 13:14:31 +0000 (UTC), harry ><http://wetakepic.com/images/2017/12/04/speakers1.jpg>   >How do we debug a scratchy sound? >We can isolate it with the balance to a single speaker.   Then it's the speaker. I'm assuming you used both the left-to-right balance and the front-to-rear fader so you were really listening to only one speaker at a time. If there is a problem in the left channel, it will be heard in both the front and rear speaker.   >But is it the speaker?   Yes.   >Or something else?   No.   >If it's the speaker, where is a good place (other than the dealer) to get   The dealer is a terrible place. Do they even sell speakers?   >speakers to fit a car rear deck? Are they all standard sizes nowadays? Or >is each unique?   Crutchfield. Very reliable. Very helpful on the phone with real people. They're in Charlotte, Va. and I'm in Baltimore and I ordered something and I wasn't in a hurry but I got it the next day.   I recommend them highly despite that they did make a mistake, like other vendors do, wrt the inputs on my 2005 Solara radio. This is the E7001 radio, but I don't think E7002 is any different. These are both Navigation radios that only hold one CD, and with some such radio, if you press the CD button twice, it goes to the CD deck, and it does have a jack for a CD deck (or satellite) and they sell devices that will use such a jack for USB/AUX input. Well that doesn't work on these radios, but they took my word for it, sent me a paid-mailing label, I sent it back as if it were new, dropped it off at a UPS place, and I got my refund the next day.   I've also bought speakers from them more than once in the past. No one else has a better list of cars and their dimensions.   You SHOULD NOT MESS with dash speakers. There was a recall on dashboards from that year and a couple others, on the Solara but I'm pretty sure on the Camry too, and some of them have deteriorated so bad they replaced the dash for free. My dash has a few hairline cracks, but when I tried to lift the 3 digital gauges above the center AC outlets, I put a tiny nick in the dash, behind the gauges. Plainly my dash, also a 2005, is softer than when it was made. (But I'm prettty sure it's nowhere near bad enough to get them to replace it for free, plus the recall has expired anyhow.) I had to go at the gauges from another direction and I did get them up, to reach the radio bolts and remove the radio (long enough to unplug that device above that didn't work. I had been able to plug it in from the bottom without removing the radio.) So there is a tiny nick there   Since you refer to the deck, I assume this is really a Camry and not a Solara, which some people call a Camry Solara. And that it's a sedan and not a convertible, because the convertibles also have a woofer behind the rear seat. I don't think it's even mentioned in the owners manual or anywhere but the wiring diagram, but it's there. >helped her kid put in new speaker covers this weekend but the scratch sound >persisted (we thought it might have been the crud or vibration from the >crumbling melted-in covers).   For crud, I would have washed the covers in the dishwasher. It does a great job on things like this. ><http://wetakepic.com/images/2017/12/04/speakers2.jpg>   >Any suggestion on how to debug the cause of the scratchiness? >If it's the speakers themselves, are these things standard sizes nowadays?   Yes, but there are lots of sizes, especially when you consider depth.

Pimpom <Pimpom@invalid.com>: Dec 04 03:59PM +0530 A Schottky diode in the standby power supply of a Panasonic TH-P42X30T plasma TV failed short but I don't have a spare or any close substitute. It's a B3100 (3A, 100V) used in a single-diode half-wave configuration.   The DC output seems to be 15V. Load current, peak reverse voltage and frequency unknown. I have some 1N5822s which have a Vr rating of only 40V.   Ordering parts from here takes a month or more. I'd like to do at least a temporary replacement of the diode and see if there's anything else wrong.   I'm thinking of using two 1N5822s in series and parallel each with a resistor to help distribute the reverse voltage evenly. Choosing a suitable resistor value wouldn't be a problem with low-leakage Si PN diodes but the 1N5822 has a published max leakage of 2mA (0.12mA typical) at Vr(max) at 25°C, 20mA at 100°C.   What value of resistors do you suggest? Is my idea at all feasible?

Look165 <look165@numericable.fr>: Dec 04 12:28PM +0100 Why changing ?   B3100 can be found at Farnell or RS for some .7€ pce   SO just replace !   idem for the transistors (it dimishes the unit shipment cost).       Pimpom a écrit :

N_Cook <diverse@tcp.co.uk>: Dec 04 12:10PM On 04/12/2017 10:29, Pimpom wrote: > diodes but the 1N5822 has a published max leakage of 2mA (0.12mA > typical) at Vr(max) at 25°C, 20mA at 100°C.   > What value of resistors do you suggest? Is my idea at all feasible?   It is the recovery time, ie frequency that is important, surely you could rob a shottky package from some SMPS somewhere?

tabbypurr@gmail.com: Dec 04 05:38AM -0800 On Monday, 4 December 2017 11:28:22 UTC, Look165 wrote:   > B3100 can be found at Farnell or RS for some .7€ pce   > SO just replace !   > idem for the transistors (it dimishes the unit shipment cost).   presumably they don't ship to india or are prohibitively expensive   I'd just try one diode, accepting it might or might not work temporarily. I'd test its Vr max first, it's regularly well above rating. But I'd not want to leave it in there even if it works, there's some reason the OEM paid extra for a shottky.     NT

tabbypurr@gmail.com: Dec 03 09:40AM -0800 On Sunday, 3 December 2017 14:41:50 UTC, N_Cook wrote: > Another consideration, any ceramic resonator filters perhaps not 40 > years back, the silver inside can migrate over the resonator edges and > make them go ohmic, losing selectivity   SAW filters got into consumer goods in the 80s. It'll be cans with slugs.   the following is more from reading than experience... Before doing any twiddling you really need to know the set up technique, it was not as simplistic as twiddle for best volume/clarity. AIUI the slugs were stagger tuned to get the best shaped response, fail to follow that method and you'll end up with really crap audio frequency response for AM, for FM I presume lousy signal capture & distortion.     NT

Chris <cbx@noreply.com>: Dec 03 06:33PM On Sun, 03 Dec 2017 07:01:42 -0600, Foxs Mercantile wrote:   > On 12/3/2017 6:54 AM, Cursitor Doom wrote: >> I've had this great old classic radio for the best part of 40 years   Time to buy a new one then!   > Dried out aluminum electrolytic capacitors.   ???

"pfjw@aol.com" <pfjw@aol.com>: Dec 03 12:59PM -0800 On Sunday, December 3, 2017 at 8:01:47 AM UTC-5, Foxs Mercantile wrote: > Jeff-1.0 > wa6fwi > http://www.foxsmercantile.com   What he wrote - AND BEFORE screwing around with slugs filters and/or any other 'adjustables" in the radio - unless you really do want to split a slug, break something and utterly destroy it. Either the caps are bad, or they are bad after 40 years, or they are bad out of sheer cussedness. And as there are no other variables that would explain the increasing deafness of the radio, start with the obvious (and necessary) before risking anything else.   Peter Wieck Melrose Park, PA

Cursitor Doom <curd@notformail.com>: Dec 03 11:50PM > And as there are no other variables that would explain the increasing > deafness of the radio, start with the obvious (and necessary) before > risking anything else.   Well, I can't argue with that philosophy; I'm all for trying the simple things first. I can't remember the last time I ran this radio off a battery, but I'll get one in the morning and try powering it up with that. I'm not sure how dried electrolytics could explain the symptoms I'm getting but am happy to at least eliminate that possibility first and this is the easiest way of going about it.       -- This message may be freely reproduced without limit or charge only via the Usenet protocol. Reproduction in whole or part through other protocols, whether for profit or not, is conditional upon a charge of GBP10.00 per reproduction. Publication in this manner via non-Usenet protocols constitutes acceptance of this condition.

Tim Schwartz <tim@bristolnj.com>: Dec 03 10:10PM -0500 > What he wrote - AND BEFORE screwing around with slugs filters and/or any other 'adjustables" in the radio - unless you really do want to split a slug, break something and utterly destroy it. Either the caps are bad, or they are bad after 40 years, or they are bad out of sheer cussedness. And as there are no other variables that would explain the increasing deafness of the radio, start with the obvious (and necessary) before risking anything else.   > Peter Wieck > Melrose Park, PA   I have to disagree about always blaming caps. 90 % of the electrolytic caps that I remove when a customer wants them all replaced are just fine, unless they are near a heat source. SOME brands and series of caps are suspect, but many are just fine. Another possibility for this radio is a bad RF amp transistor or something similar elsewhere. For example, in many old tuners you are more likely to find bad LM703 IF IC's than a bad cap, especially if the IC is the dome-topped variety, the metal cans are much better. Bad soldering or dirty tuning cap grounds are also common issues.   Regards, Tim

Tim Schwartz <tim@bristolnj.com>: Dec 03 10:12PM -0500 > What he wrote - AND BEFORE screwing around with slugs filters and/or any other 'adjustables" in the radio - unless you really do want to split a slug, break something and utterly destroy it. Either the caps are bad, or they are bad after 40 years, or they are bad out of sheer cussedness. And as there are no other variables that would explain the increasing deafness of the radio, start with the obvious (and necessary) before risking anything else.   > Peter Wieck > Melrose Park, PA   I have to disagree about always blaming caps. 90 % of the electrolytic caps that I remove when a customer wants them all replaced are just fine, unless they are near a heat source. SOME brands and series of caps are suspect, but many are just fine. Another possibility for this radio is a bad RF amp transistor or something similar elsewhere. For example, in many old tuners you are more likely to find bad LM703 IF IC's than a bad cap, especially if the IC is the dome-topped variety, the metal cans are much better. Bad soldering or dirty tuning cap grounds are also common issues.   Regards, Tim

tabbypurr@gmail.com: Dec 03 09:24PM -0800 On Sunday, 3 December 2017 23:50:37 UTC, Cursitor Doom wrote: > battery, but I'll get one in the morning and try powering it up with > that. I'm not sure how dried electrolytics could explain the symptoms I'm > getting but am happy to at least eliminate that possibility first and   obviously that does not eliminate the possibility.

"pfjw@aol.com" <pfjw@aol.com>: Dec 04 04:54AM -0800 On Sunday, December 3, 2017 at 10:10:47 PM UTC-5, Tim Schwartz wrote:   > fine, unless they are near a heat source. SOME brands and series of > caps are suspect, but many are just fine.   > Tim   Tim:   Likely the caps in this beast are Frako, even if re-branded. May as well write FlakO. So, at the very least they are suspect as you suggest. And if he has been running it off mains power, there may well be some heat involved.   Furthermore, this is a German Radio - meaning that Grundig never used one part where three-or-more would do better. Dealing with the caps - a necessary exercise in any case - may cure the problem. At worst, the effort is not wasted.   Peter Wieck Melrose Park, P

vjp2.at@at.BioStrategist.dot.dot.com: Dec 04 05:06AM Funny outcome:   mention of capacitors made me think, "What if I leave it on a long time?"   Indeed, After like six hours, it turned on (the GW2k P5).   I'm using it now to dialup to unix Now, I'm afraid to shut it off.   What cause dit to "die" in the first place was I hadn't used it in a long while       - = - Vasos Panagiotopoulos, Columbia'81+, Reagan, Mozart, Pindus blog: panix.com/~vjp2/ruminatn.htm - = - web: panix.com/~vjp2/vasos.htm facebook.com/vasjpan2 - linkedin.com/in/vasjpan02 - biostrategist.com ---{Nothing herein constitutes advice. Everything fully disclaimed.}---

walter_evening@post.com: Dec 03 10:00AM -0800 6:08th Minute Of The Following (Overseas) Star Trek Youtube Video Game Video..   -- https://www.youtube.com/watch?v=QJxyc7qAB-0

tschw10117@gmail.com: Dec 03 07:30PM -0800 > 6:08th Minute Of The Following (Overseas) Star Trek Youtube Video Game Video..   > -- https://www.youtube.com/watch?v=QJxyc7qAB-0   Never watched Voyager? It's Chakotay's tattoo.

"fynnashba@yahoo.com" <fynnashba@yahoo.com>: Dec 03 10:23AM -0800 Please i am working on a samsung Refrigerator which had a problem with the compressor(inverter type). There was a similar working samsung refrigerator (different model) so the Mechanic i was working with swap the compressors but did not work. l tried checking the voltage at all the three terminals feeding the compressor but no voltage (both ac and dc). surprisingly when we fixed another compressor from the same model it worked. What i don't understand is how will the compressor work when no voltage is present? The compressor has three pins which reads 14 ohms all round. Please i will be very happy if the expects here can explain things to me. Thanks in advance.

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