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captainvideo462009@gmail.com: Nov 07 04:06PM -0800 This is my own receiver. It is mounted and wired into my home entertainment system cabinet. I rescued it from the junk pile about 35 years ago and for the first ten years or so it worked flawlessly. At one point though I began to notice that For some time the channel on the far right side, (looking at the front of the unit) was lower than the rest. At some point it quit completely and I just used it on two channels.   Last year I got the chance to pick up one of these receivers for parts. I cleaned mine all up and swapped the two four channel boards from the organ donor into mine. I bench tested it for weeks before returning it to the cabinet.The unit worked great for three days after which I once again lost that fourth channel.   I hate to shotgun repairs but this is a very difficult receiver to service because boards were built one on top of another. In other places switch banks are obstructed by component placement and you have to disassemble a lot of stuff to get at what you're after. In short when it's working it's great but just hope and pray that you'll never have to service it. It's your basic nightmare.   Over time, I worked on this fourth channel problem, John Del who is one of the finest technicians I know worked on it and I even had it to a repair center outside of Boston. None of us had any luck. So not wanting to haul this 85 pound monster back down to the shop once again I just resigned myself to just using it as a two channel receiver.   Then last night something happened that piqued my interest and changed my mind. We were watching a TV show on the lap top. The computer's headphone jack was plugged into a line input on the receiver. For whatever reason the program audio was very low so we had the receiver volume level cranked up. After the program ended my wife unplugged the 3.5mm plug from the computer without first dropping the receiver audio level. The sound was something you don't ever want to hear. I thought that I had just lost three working channels as well as the speakers.   But to my relief everything seemed OK. And in fact after the "event" the previously non working fourth channel was once again working perfectly. So for a brief time I sat back and enjoyed some four channel music as it should sound. I shut it off last night and this morning I wasn't surprised to find that the channel was out again.   I seem to remember working on some of the receivers of the day back in the mid 70's and I recall that we had problems with flaky FET's. The receiver would start crackling and touching a hot soldering iron to the bad FET would either fix the problem or make it worse. Of course whatever component it may be because of the way it was built, finding the bad one in this receiver could be next to impossible.   There was gentleman who I spoke with in the past on this forum about this receiver. It seems that he used to work on them and he was a wealth of information. His name was chuck but I don't have his email address. Does anyone know how to get in touch with him? In any event if anyone has any insight on this problem I would sincerely appreciate your input. Thanks, Lenny

abrsvc <dansabrservices@yahoo.com>: Nov 07 04:19PM -0800 Believe it or not, this is a common failure. The protection relays get a bit of corrosion on them and don't pass the signal along. You can try cleaning the contacts or just replace the relays. The increased signal level of the higher volume can sometimes "span the gap" and appear to work OK.   Dan

Trevor Wilson <trevor@rageaudio.com.au>: Nov 08 02:28PM +1100 > But to my relief everything seemed OK. And in fact after the "event" the previously non working fourth channel was once again working perfectly. So for a brief time I sat back and enjoyed some four channel music as it should sound. I shut it off last night and this morning I wasn't surprised to find that the channel was out again.   > I seem to remember working on some of the receivers of the day back in the mid 70's and I recall that we had problems with flaky FET's. The receiver would start crackling and touching a hot soldering iron to the bad FET would either fix the problem or make it worse. Of course whatever component it may be because of the way it was built, finding the bad one in this receiver could be next to impossible.   > There was gentleman who I spoke with in the past on this forum about this receiver. It seems that he used to work on them and he was a wealth of information. His name was chuck but I don't have his email address. Does anyone know how to get in touch with him? In any event if anyone has any insight on this problem I would sincerely appreciate your input. Thanks, Lenny   **Output relays. Replace 'em or clean em. Very common in 40 ~ 50 year old equipment. In fact, I have a Sansui AU919 with precisely that problem.   -- Trevor Wilson www.rageaudio.com.au

Phil Allison <pallison49@gmail.com>: Nov 07 07:51PM -0800 Trevor Wilson wrote:   -----------------------   > **Output relays. Replace 'em or clean em. Very common in 40 ~ 50 year > old equipment. In fact, I have a Sansui AU919 with precisely that problem.   ** Certainly true.   I can spend hours on an old Jap receiver, from one of the major brands before it is all working again.   Corroded toggle, pushbutton and rotary switches, pots, RC sockets, multi-pin connectors, wire wrap joints, fuse clips, bulb sockets, noisy tuning gang bearings, bad headphone jacks, dead back lights and maybe a few leaky or open electros. Plus of course speaker relays.   Almost nothing in parts, but heaps of time that must be paid for.       ..... Phil

Trevor Wilson <trevor@rageaudio.com.au>: Nov 08 07:46PM +1100 On 8/11/2019 2:51 pm, Phil Allison wrote:   > I can spend hours on an old Jap receiver, from one of the major brands before it is all working again.   > Corroded toggle, pushbutton and rotary switches, pots, RC sockets, multi-pin connectors, wire wrap joints, fuse clips, bulb sockets, noisy tuning gang bearings, bad headphone jacks, dead back lights and maybe a few leaky or open electros. Plus of course speaker relays.   > Almost nothing in parts, but heaps of time that must be paid for.   **My AU919 customer was real lucky. He bought it from a US seller on eBay. It arrived in it's original packing box. When I pulled it out, I realised that it had seen very little use, based on how much dust was inside and the cosmetic condition of the knobs and switches. It's probably the best one I've ever seen. Replacing the deadly 'black flag' caps with silvered mica (at the customer's request) and ceramics, two new relays (I could have cleaned them, but what the Hell, they were only 9 Bucks each from RS) and the job is done.   However, next week, I face off with this beast:   https://classicreceivers.com/marantz-4400 https://www.hifiengine.com/manual_library/marantz/4400.shtml   Built to be easily repaired in case of an output stage fault (which hardly ever happens).   One of my all-time favourites. I repaired quite a few back in my Marantz days. Nicely built, but crowded. Replacing the lamps is a nightmare. The CRO doesn't work, but I am hopeful it's a power supply issue. A full set of electros, lamps and all the other stuff will take me the best part of all week to sort out. Worth it though. Arguably, the best, most desirable 4 channel receiver ever made.   Gotta love those hipsters. :-)   -- Trevor Wilson www.rageaudio.com.au

Adrian Caspersz <email@here.invalid>: Nov 08 10:53AM On 08/11/2019 00:19, abrsvc wrote: > Believe it or not, this is a common failure. The protection relays get a bit of corrosion on them and don't pass the signal along. You can try cleaning the contacts or just replace the relays. The increased signal level of the higher volume can sometimes "span the gap" and appear to work OK.   Or mechanical stress on the circuit board jolts the contacts.   -- Adrian C

Fred McKenzie <fmmck@aol.com>: Nov 07 12:32PM -0500 In article <qq0pj6$56v$1@neodome.net>,   > What adhesive to repair nylon halved pencil sharpener gear? > http://img4.imagetitan.com/img.php?image=20_image5623.jpg > If it fails, what online pencil sharpener do you recommend?   This does not answer your question, but may be the best approach:   <http://www.xacto.com/products/office-solutions/pencil-sharpeners/detail/ 1031>   Fred

Fletcher <fletcherfletch@example.com>: Nov 07 12:58PM -0500 Sometime around Thu, 7 Nov 2019 08:57:26 -0500, Tim Schwartz <tim@bristolnj.com> wrote.....     > "Boston pencil sharpener gear" and find several choices.   > Regards, > Tim   It probably will not work but I'll try to glue it just once. If that fails, I'll junk it for parts.   To replace the gear I first called Newell Office Company under Exacto in Statesville NC 800-879-4868 but they no longer support the Boston Model 18 Electric Pencil Sharpener 296A so they won't sell a replacement gear.   I assumed it's nylon where it must be a really bad design given that it breaks a lot in the same spot on the net https://youtu.be/TExVKWyZx20 so if an expoxy or cyanacrylate doesn't work I probably should choose a more reliable brand than this crummy Boston brand.   Like you said there are 3D replacements online I could buy. There's even a "tinkercad" model file https://www.thingiverse.com/thing:267626 but I don't have a 3D printer to print it https://www.tinkercad.com/things/6nqhKOHp530   Someone suggest a better brand they like that's better than crummy Boston?

TheExperimenter <theexp8712@noaol.net>: Nov 07 01:56PM -0500 On 11/7/19 4:53 AM, Fletcher wrote: > What adhesive to repair nylon halved pencil sharpener gear? > http://img4.imagetitan.com/img.php?image=20_image5623.jpg > If it fails, what online pencil sharpener do you recommend?   Ten years ago, I had to bond a wire spool to a plastic tub. Both the spool and tub were soft plastics, nylon and polypropylene, respectively. I used this: https://tinyurl.com/y3z5cnyn   For three years, in temperatures from 15- 90 F, the bond held fine and allowed me to wind and unwind wire around the spool. Then, one night, it came apart after I had bumped the assembly against the door heading outdoors. However, for the cost, I felt that the plastic bonder did the job. You can find it just about anywhere, home improvement stores and such. Good luck.

amdx <nojunk@knology.net>: Nov 07 03:04PM -0600 On 11/7/2019 4:26 AM, Phil Allison wrote:   > .... Phil   Phil has the winner for me, I have local fastener company, that would find me a washer or two I could work with, but aluminum is so easy to work with, your choice. That said, I have drilled 0.025" holes and placed a 0.025" rod in the hole to put two pieces back together, always used an epoxy with it but wasn't sure the epoxy did much on some of the repairs. Sometimes used two rods in different areas. Buy for this, I like Phil's idea! Mikek

micky <NONONOaddressee@rushpost.com>: Nov 07 04:20PM -0500 In alt.home.repair, on Thu, 07 Nov 2019 12:32:59 -0500, Fred McKenzie   >This does not answer your question, but may be the best approach:   ><http://www.xacto.com/products/office-solutions/pencil-sharpeners/detail/1031>   >Fred   An excellent idea. Probaby will last for 30 years.   We had one where the handle cyclinder fell off, but my mother kept the cylinder and the rivet and I pounded the rivet down a bit and it jst about good as new. I still have it somewhere but I use a knife to sharpen pencils.   Ours didn't even suck in the pencil. You had to push it in. Worked just fine.

Phil Allison <pallison49@gmail.com>: Nov 07 03:54PM -0800 amdx wrote:   ---------------------   > Phil has the winner for me, I have local fastener company, that would > find me a washer or two I could work with, but aluminum is so easy to > work with, your choice.   ** Guaranteed to work, long as 1mm extra thickness is not an issue.     .... Phil

TheExperimenter <theexp8712@noaol.net>: Nov 07 12:08PM -0500 On 11/7/19 4:07 AM, Martin Brown wrote:   > https://www.youtube.com/watch?v=3FpjcOWwiI4   > (skip the first minute of dross)   > This would stop your attacker but it isn't very portable.   I agree, it would. I've built Tesla coils in the past, nothing like the ones they used there, but typical NST driven units. Nothing beyond 5" sparks, but it was fun.

TheExperimenter <theexp8712@noaol.net>: Nov 07 12:42PM -0500 On 11/6/19 11:50 PM, Jasen Betts wrote: >> volts advertised.   > It's about 3000V/mm so ballpark 35kV   > 35GV would produce gamma rays.   Well, I think I stand corrected here because I didn't give the device enough credit (thinking it was only about 20 kV). However, after rechecking the spark gap distance and using the fomula (kV) = 76.2 x spark length (in inches) with the spark gap being 3/8", that comes out to 28.5 kV. From the tingles I experienced, I suspect the resistance of the body greatly reduces that which is why the device isn't effective.

TheExperimenter <theexp8712@noaol.net>: Nov 07 01:21PM -0500 On 11/6/19 11:19 PM, Ralph Mowery wrote:   > The 35 billion volts would probably throw an arc miles long.   > Lightning is reported ot have from 100 million to 1 billion volts.   > Tasers are only around 50,000 volts   All of this is very true. I'm surprised they can get away with such false advertising for years, but no one seems willing to do anything about the dysfunctional phone system in the US either.

bitrex <user@example.net>: Nov 07 02:02PM -0500 On 11/7/19 4:07 AM, Martin Brown wrote: >> was time to see just how much relevancy there was behind it.  Now it >> should be clear.  Bye.   > Darwin award candidate.   Put the thing in a different enclosure and it's a bedroom "toy" for the "open minded" couple.

TheExperimenter <theexp8712@noaol.net>: Nov 07 02:14PM -0500 On 11/7/19 2:02 PM, bitrex wrote:   > Put the thing in a different enclosure and it's a bedroom "toy" for the > "open minded" couple.     http://tiny.cc/t8nwfz

TheExperimenter <theexp8712@noaol.net>: Nov 07 12:15PM -0500 On 11/4/19 2:24 PM, Al Butterworth wrote: > Looking for a source for getting NO diode embedded flybacks to be able > to run multiplier circuits, etc.  I am in the US.  Thank you.   > AB   Ebay seems to have the AC ones, but take a good close look at the condition before purchase. You can sometimes google the part numbers of the advertised device and come across a TV manual showing KV output of the transformer if that's important.

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