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Stu jaxon <stankowalski02@gmail.com>: Mar 03 07:28AM -0800 Hi Group, can someone help please, I replaced the main board 3655-0342-0150(41)... on a Vizio M550SV, the hdmi ports do not work. I resoldered the pins, and followed the suggestions in coppell tv repair video for a short did not find one,,,.. https://www.youtube.com/watch?v=8U-01HUx0qY. any help in this matter will be taken seriously, Thanks,

World wide137 <worldwide137@gmail.com>: Mar 02 06:23PM -0800 Hello Folks. I need some help in identifying a ceramic capacitor on an RF signal generator from the 50's. The capacitor is off the power supply. The shape is a circular disk about 1cm in diameter with the following markings - HI-Q 2X .01. Any help greatly appreciate.

Phil Allison <pallison49@gmail.com>: Mar 02 06:35PM -0800 worldw...@gmail.com wrote:   ========================== > Hello Folks. I need some help in identifying a ceramic capacitor on an RF signal generator from the 50's. The capacitor is off the power supply. The shape is a circular disk about 1cm in diameter with the following markings - HI-Q 2X .01.   ** Is is dual cap with 3 legs like this one ?   https://www.ebay.com/itm/Vintage-1960s-Ceramic-Disk-Circle-D-Capacitor-2x-01-uf-1-4kv-Guitar-Tone-02-/123856474984   A pic would be useful.     ..... Phil

World wide137 <worldwide137@gmail.com>: Mar 02 06:43PM -0800 Thanks Phil. The capacitor has two legs, here's a picture of it. -Norm   http://printque.us/capacitor.png

World wide137 <worldwide137@gmail.com>: Mar 02 06:51PM -0800 I should mention that this capacitor is in a Precision signal generator, model E-200-C.

Phil Allison <pallison49@gmail.com>: Mar 02 07:17PM -0800 worldw...@gmail.com wrote:   ================================= > I should mention that this capacitor is in a Precision signal generator, model E-200-C.   That cap is in the AC supply circuit - right? See bottom of this page:   https://www.antiqueradios.com/forums/viewtopic.php?f=8&t=363692   So it's a high voltage, ceramic cap.   Good replacement would be a 0.01uF, 2kV ceramic like this:   https://www.mouser.com/ProductDetail/TDK/CK45-E3DD103ZYVNA/?qs=eSfX1CQlHqqfWLOcs5KSTQ%3D%3D   Many other sources.     ......... Phil

Phil Allison <pallison49@gmail.com>: Mar 02 10:00PM -0800 Phil Allison wrote: ================= > Good replacement would be a 0.01uF, 2kV ceramic like this:   > https://www.mouser.com/ProductDetail/TDK/CK45-E3DD103ZYVNA/?qs=eSfX1CQlHqqfWLOcs5KSTQ%3D%3D   > Many other sources.   ** Be nice idea to fit a 3- core power lead and earth the thing while you are at it.       ..... Phil

"Peter W." <peterwieck33@gmail.com>: Mar 03 05:47AM -0800 That looks very much like an older ceramic safety capacitor. 2X today would be written as X2. That being "X-type, Ceramic Class 2". Their purpose is to minimize EMI/RFI interference - something that makes sense in an SG.   The X means that it is to go between the line-cord leads (hot and neutral). 2X means it will tolerate a peak voltage pulse of 2,500 while in operation.   More explanation here: https://www.allaboutcircuits.com/technical-articles/safety-capacitor-class-x-and-class-y-capacitors/   Mouser-available Vishay-made device here: https://www.mouser.com/datasheet/2/427/564r565r-1762222.pdf   Peter Wieck Melrose Park, PA

World wide137 <worldwide137@gmail.com>: Mar 03 06:00AM -0800 Phil - Appreciate the input and link to Mouser. I've contemplated replacing with a 3-prong cord but there seems to be some who say a two prong is better for a sound generator as to not pick up any interference off the ground from other devices. I'm a hobbyist so my depth of knowledge isn't so deep as to accept or refute their claims so I've just left it for now. Cheers. -Norm   On Wednesday, March 3, 2021 at 1:00:06 AM UTC-5, wrote:

"Peter W." <peterwieck33@gmail.com>: Mar 03 06:23AM -0800 www.antiqueradios.com/forums/viewtopic.php?f=8&t=363692   https://www.byan-roper.org/steve/_Media/e-200-schematic.jpeg   Might help in the restoration process.   On the 2/3 conductor line cord: If you look at the schematic - there are two (2) 0.01uF safety caps in series with a ground between them - which is the same common ground throughout the system. And, by the way, those are X-types as the are between the hot and the neutral. I will not presume that the common ground is also the case even though that is both very likely and common, but you can check that easily yourself - is there continuity between the case and the chassis? If so, go ahead and install a 3-wire cord, grounding to the case. If not do some more checks before going to three wires so that you do not cause any damage. Also, when the device is in operation, is there any leakage (VOM on AC, case-to-good-ground: Any voltage showing?)?   Peter Wieck Melrose Park, PA

World wide137 <worldwide137@gmail.com>: Mar 03 06:24AM -0800 Peter - Thank you for the explanation, I had a heck of a time looking for this on Google. I guess, I wasn't sure on how to search for it. Searching for what was printed on the actual capacitor did not bring up much. Here is a picture of the whole thing. This capacitor is run across the the two chokes. Cheers. -Norm   http://printque.us/IMG_5103.jpg     On Wednesday, March 3, 2021 at 8:47:57 AM UTC-5, Peter W. wrote:

"Peter W." <peterwieck33@gmail.com>: Mar 03 06:48AM -0800 Norm:   A few things:   a) There are many versions of this unit over the years, so the differences between the schematic and what you have are no surprise. b) There is no reason to remove the tubular ceramic caps - I believe that the restoration page does mention that. They tend to be pretty stable over the years. c) I would restore to the schematic as shown: http://www.byan-roper.org/steve/_Media/img_5750_med.jpeg d) I see where the ground lug is riveted to the copper cover - and that the cover appears to be sheet-metal-screwed to the case. If so, a 3-wire cord is good, with the ground wire going to the center lug of the three.   Take your time. That is a 'popular' unit within the hobby, and worth the effort if you want vintage service gear to go with the vintage radios.   Peter Wieck Melrose Park, PA

World wide137 <worldwide137@gmail.com>: Mar 03 06:57AM -0800 You are correct, Peter, that is how the copper cover interacts with the case. There has indeed been several updates to this model, I have 4 different schematics, all similar but slightly different. Of the four, none matches my version perfectly. Thanks again for you input, they've been very helpful. Cheers. -Norm   On Wednesday, March 3, 2021 at 9:48:18 AM UTC-5, Peter W. wrote:

Tim R <timothy42b@aol.com>: Mar 02 10:23AM -0800 On Tuesday, March 2, 2021 at 5:01:10 AM UTC-5, Abandoned_Trolley wrote:   > Speaking of which ... I believe some musicians are able to tune their > instruments by using the dial tone from a landline as a reference.   > AT   Wiki says the dial tone is a combination of 350 and 440 Hz. That would be an F major chord, minus the fifth. I guess you could do that. Youtube had a 12 hour long recording of a dial tone. I just tried to tune a guitar A string to that, came out 3 cents sharp by my tuner. But my tuner hears the dial tone as an F. The youtube version sounds like a square wave to my ears though.   The 60 cycle power hum doesn't work, it is halfway between a Bb (58) and a B natural (62).

mjb@signal11.invalid (Mike): Mar 02 09:20PM In article <s1l2d3$o2j$1@dont-email.me>,   >Speaking of which ... I believe some musicians are able to tune their >instruments by using the dial tone from a landline as a reference.   That's a great idea, but it probably mean FA to most people.   Musicians, on the other hand ... :)   -- --------------------------------------+------------------------------------ Mike Brown: mjb[-at-]signal11.org.uk | http://www.signal11.org.uk

Tim R <timothy42b@aol.com>: Mar 02 03:29PM -0800 On Tuesday, March 2, 2021 at 4:22:06 PM UTC-5, Mike wrote:   > >Speaking of which ... I believe some musicians are able to tune their > >instruments by using the dial tone from a landline as a reference. > That's a great idea, but it probably mean FA to most people.   Doesn't mean much to musicians either.   Most of us don't have land lines.   Most of us do have cell phones and you can get free tuning apps on them.   Or you can get a decent electronic tuner for $20.   Those two things have made a huge difference in stabilizing a pitch center. Years back you never knew what pitch a band was going to have - might be 440, 415, 175, who knows? You had to be prepared to accommodate, and some instruments could only be tuned so far. Now amateurs don't play any better in tune, but they play out of tune around an agreed upon pitch, and that makes it a lot easier.   What you hear on recordings is always autotuned. I don't understand how that works, but it may be gradually training people to expect things to be in tune. Except Sailor Sabor, of course, who holds the record for the most out of tune National Anthem ever, at the CPAC 2021 last week.

Phil Allison <pallison49@gmail.com>: Mar 02 05:16PM -0800 Tinkerer wrote: > scale really. Output is from 200 Hz - 2 Khz on "low" and 2 Khz to 20 > Khz on "high". Exact frequency depends on where the pot is adjusted. > How can I calibrate this to be more precise, preferably in a simple way?   ** This link might be useful:   https://www.szynalski.com/tone-generator/   It's a variable frequency sine/square generator covering 1Hz to 20kHz with digital read out.   You can use zero beating if mixed with the output of your Heathkit unit.   ..... Phil

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"ohg...@gmail.com" <ohger1s@gmail.com>: Mar 01 03:18PM -0800 > Silver sulphide would form on the plating, travel into the device and eat the chip.   > Always Jap stuff like Marantz.   > ..... Phil   Yep. I think Chuck one post up identified the number.

Phil Allison <pallison49@gmail.com>: Mar 01 03:23PM -0800 ohg...@gmail.com wrote:   ===============   > > Silver sulphide would form on the plating, travel into the device and eat the chip.   > > Always Jap stuff like Marantz.   > Yep. I think Chuck one post up identified the number.   ** See:   https://www.oneonetwo.com/2013/07/vintage-transistors-2sc458-hitachi.html   That looks *horribly " familiar....     .... Phil

legg <legg@nospam.magma.ca>: Mar 02 09:10AM -0500 On Sat, 27 Feb 2021 12:27:16 -0800 (PST), "ohg...@gmail.com"   >> Then there is this quad unit, outputs good but it had more bad transistors than you could sweep off the floor. get the amp fixed and a channel is cutting out. Bad connection ? Nope, a transistor. Got that fixed and now off to another board that is no doubt full of bad transistors.   >> Life is trip, think of the destination.   >The only time I really remember transistors being a red flag (other than early Germaniums) were some small Hitachi signal transistors from the 70s-80s - the TO-92 ones with the beveled top. Those things would go leaky or open or intermittent (their choice). It got to the point back then that I just automatically changed them whenever I saw one in anything I worked on. Pretty much eliminated any rechecks.   We had an issue with parts in TO98, which was a common package for early GE plastic signal transistors. 2N339x 2n34xx. These were encapsulated off-shore, possibly even a simple rebrand.   At the time, there was a suspicion that they weren't normal supply chain product, as the bad parts were purchased through brokers.   Although conforming to TO98 outline, they were a filled-epoxy package, vs a molded epoxy. Anything showing up with the filled-epoxy construction was simply dumped at incoming inspection. Rubbish.   RL

"ohg...@gmail.com" <ohger1s@gmail.com>: Mar 02 06:47AM -0800 On Tuesday, March 2, 2021 at 9:09:12 AM UTC-5, legg wrote: > filled-epoxy construction was simply dumped at incoming > inspection. Rubbish.   > RL   We've all seen flat out counterfeits. When I used to repair an amplifier with blown outputs, I used to return them along with a copy of my do's and don'ts - things like checking for wayward strands of speaker wires, looking for speaker wires punctured under carpet strips, not doubling up speakers on one terminal block, leaving sufficient ventilation on top of the amplifier, etc. I remember when I had amplifiers coming back with reblown outs, and I blamed the customer. Turns out the semis I was buying were counterfeits, and it wasn't just audio transistors. We ran into this problem with television vertical output ICs, power supply ICs, horiz (line) outputs, STK convergence modules, and even Sony jungle ICs.. I remember going through my parts supply and tossing a good portion of them out and making sure to buy from only reputable suppliers or directly from the OEM.

Tim R <timothy42b@aol.com>: Mar 01 09:04AM -0800 Cheap USB microphone, laptop, Audacity? (Audacity is free recording software with lots of extras, does frequency, etc)

liz@poppyrecords.invalid.invalid (Liz Tuddenham): Mar 01 07:46PM > scale really. Output is from 200 Hz - 2 Khz on "low" and 2 Khz to 20 > Khz on "high". Exact frequency depends on where the pot is adjusted. > How can I calibrate this to be more precise, preferably in a simple way?   Beat it with mains hum. This should work on the low range and at least part of the way up the high range.   -- ~ Liz Tuddenham ~ (Remove the ".invalid"s and add ".co.uk" to reply) www.poppyrecords.co.uk

Phil Allison <pallison49@gmail.com>: Mar 01 11:56AM -0800 Liz Tuddenham wrote:   =-===================   > > How can I calibrate this to be more precise, preferably in a simple way?   > Beat it with mains hum. This should work on the low range and at least > part of the way up the high range.   ** You need to explain that idea.   The OP seems to have no test gear or clue.   ...... Phil

Tinkerer <tinker5@anytime.net>: Mar 01 04:07PM -0500 On 3/1/21 12:04 PM, Tim R wrote: > Cheap USB microphone, laptop, Audacity? (Audacity is free recording software with lots of extras, does frequency, etc)   Great idea. I have Audacity. I could just play the audio output and either capture with mic or feed into soundcard and then see what it is in Audacity. I think that's what I'll do, although I like Phil's suggestion of a DVM with freq counter, been keeping an eye out for one.

Tinkerer <tinker5@anytime.net>: Mar 01 04:09PM -0500 On 3/1/21 2:46 PM, Liz Tuddenham wrote: >> How can I calibrate this to be more precise, preferably in a simple way?   > Beat it with mains hum. This should work on the low range and at least > part of the way up the high range.   Not sure what that means, unless you mean a harmonic of 50/60 Hz. It might be possible to beat by ear if the PC generates the tone and I adjust the generator until it matches by ear, but I think I'm just going to use Audacity and/or a DWM with freq ctr as suggested by Phil.

Bennett <bjprice@cal.berkeley.edu>: Mar 01 09:09PM -0800 On 3/1/2021 1:09 PM, Tinkerer wrote: > might be possible to beat by ear if the PC generates the tone and I > adjust the generator until it matches by ear, but I think I'm just going > to use Audacity and/or a DWM with freq ctr as suggested by Phil.   Google Online Music Tuner In the US the note A is generally considered 440HZ This one gives the frequency in Hz https://bit.ly/383gzou

Abandoned_Trolley <fred@fred-smith.uk>: Mar 02 10:01AM On 02/03/2021 05:09, Bennett wrote: >> going to use Audacity and/or a DWM with freq ctr as suggested by Phil.   > Google  Online Music Tuner  In the US the note A is generally considered > 440HZ  This one gives the frequency in Hz  https://bit.ly/383gzou       Speaking of which ... I believe some musicians are able to tune their instruments by using the dial tone from a landline as a reference.   AT

Phil Allison <pallison49@gmail.com>: Mar 02 04:11AM -0800 Abandoned_Trolley wrote: ======================   > Speaking of which ... I believe some musicians are able to tune their > instruments by using the dial tone from a landline as a reference.   ** But only after taking a huge dose of Meth first.     ...... Phil

bilou <bilou@sfr.fr>: Mar 02 02:34PM +0100 On 01/03/2021 18:04, Tim R wrote: > Cheap USB microphone, laptop, Audacity? (Audacity is free recording software with lots of extras, does frequency, etc)   If you have a PC with a decent sound card you don't need an audio frequency generator :-)

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Tinkerer <tinker5@anytime.net>: Feb 28 04:27PM -0500 I have a Heathkit ET-3100 electronic design experimenter that has a very basic sine/ square wave function generator. Controls all analog and no scale really. Output is from 200 Hz - 2 Khz on "low" and 2 Khz to 20 Khz on "high". Exact frequency depends on where the pot is adjusted. How can I calibrate this to be more precise, preferably in a simple way?

"ohg...@gmail.com" <ohger1s@gmail.com>: Feb 28 01:50PM -0800 On Sunday, February 28, 2021 at 4:27:15 PM UTC-5, Tinkerer wrote: > scale really. Output is from 200 Hz - 2 Khz on "low" and 2 Khz to 20 > Khz on "high". Exact frequency depends on where the pot is adjusted. > How can I calibrate this to be more precise, preferably in a simple way?   Frequency counter. They have cheap Chinese kits on ebay that should give you readings close enough to what that generator would be used for.

Phil Allison <pallison49@gmail.com>: Feb 28 02:53PM -0800 Tinkerer wrote: ============== > scale really. Output is from 200 Hz - 2 Khz on "low" and 2 Khz to 20 > Khz on "high". Exact frequency depends on where the pot is adjusted. > How can I calibrate this to be more precise, preferably in a simple way?   ** Time to get a Digital Multimeter with a frequency range. Not crazy expensive and damn useful. Plus very accurate.       ...... Phil

gray_wolf <g_wolf@howling_mad.com>: Feb 28 09:25PM -0600 On 28/02/2021 3:27 pm, Tinkerer wrote: > Output is from 200 Hz - 2 Khz on "low" and 2 Khz to 20 Khz on "high".  Exact > frequency depends on where the pot is adjusted. How can I calibrate this to be > more precise, preferably in a simple way?   Borrow a freq counter?

Abandoned_Trolley <fred@fred-smith.uk>: Mar 01 11:08AM On 28/02/2021 21:27, Tinkerer wrote: > scale really.  Output is from 200 Hz - 2 Khz on "low" and 2 Khz to 20 > Khz on "high".  Exact frequency depends on where the pot is adjusted. > How can I calibrate this to be more precise, preferably in a simple way?     One of those cheap digital guitar tuners things might point you in the right direction ? (everybody knows somebody who plays the guitar)   I believe there are smartphone apps which display the frequency of the signal coming in to the microphone - whilst recording it. Theres one (of many) examples at https://audio-frequency-counter.soft112.com   Or if you know anybody with Cubase (or similar) recording software you could get them to fire up the built in digital tuner tool and see it in glorious technicolor   AT

Chris Jones <lugnut808@spam.yahoo.com>: Mar 01 10:58AM +1100 On 01/03/2021 03:16, Peter W. wrote:   >> As long as it does not actually get charged before or during the time >> that it is near the sensitive circuitry, it should not cause damage.   > There is a very long stretch between "should not" and "will not". When the proper means-and-methods are readily available, one *should not* take the lesser path.   Ordinary insulating tapes can be used in the proximity of ordinary electronics, and it would be misleading to claim otherwise. If the circuit includes small-signal mosfets with unprotected gates, then I would consider taking more precautions, but those have been uncommon for many decades.

Chuck <chuck23@dejanews.net>: Feb 28 12:23PM -0600 On Sat, 27 Feb 2021 12:27:16 -0800 (PST), "ohg...@gmail.com"   >> Then there is this quad unit, outputs good but it had more bad transistors than you could sweep off the floor. get the amp fixed and a channel is cutting out. Bad connection ? Nope, a transistor. Got that fixed and now off to another board that is no doubt full of bad transistors.   >> Life is trip, think of the destination.   >The only time I really remember transistors being a red flag (other than early Germaniums) were some small Hitachi signal transistors from the 70s-80s - the TO-92 ones with the beveled top. Those things would go leaky or open or intermittent (their choice). It got to the point back then that I just automatically changed them whenever I saw one in anything I worked on. Pretty much eliminated any rechecks.   It was the 2SC458s.

Phil Allison <pallison49@gmail.com>: Feb 28 12:07PM -0800 ohg...@gmail.com wrote: =======================   > The only time I really remember transistors being a red flag (other than early Germaniums) were some small Hitachi signal transistors from the 70s-80s - the TO-92 ones with the beveled top. Those things would go leaky or open or intermittent (their choice). It got to the point back then that I just automatically changed them whenever I saw one in anything I worked on.   ** You talking about the the dreaded " black leg corrosion" problem ? TO92s and the like with silver plated leads.   Silver sulphide would form on the plating, travel into the device and eat the chip.   Always Jap stuff like Marantz.   ..... Phil

Fox's Mercantile <jdangus@att.net>: Feb 28 12:04PM -0600 On 2/28/21 7:09 AM, bruce bowser wrote: > Cut it too long, the boss might gripe. Cut it too short, you're fired.   On one of the install jobs I was on, we had just pulled a 24 pair fiber optic cable. The installer connected 12 pairs to the devices already in the cabinet. The proceeded to cut off the remaining end flush with the box. "They were in the way."     -- "I am a river to my people." Jeff-1.0 WA6FWi http:foxsmercantile.com

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