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John-Del <ohger1s@gmail.com>: Oct 08 03:29PM -0700 Works, but I don't need it. No probes. Price negotiable but I won't go less than free..   However, I won't ship it. If you want it, it's in central CT (06706).   delstv/at\aol/dot\com   John

jurb6006@gmail.com: Oct 08 04:13PM -0700 On Monday, October 8, 2018 at 5:29:21 PM UTC-5, John-Del wrote:   > However, I won't ship it. If you want it, it's in central CT (06706).   > delstv/at\aol/dot\com   > John   I would be interested. I might be able to have it picked up, or, how much would the shipping cost ? And actually though I am low on money, I got stuff. Post a wish list.

John-Del <ohger1s@gmail.com>: Oct 09 08:55AM -0700 > > delstv/at\aol/dot\com   > > John   > I would be interested. I might be able to have it picked up, or, how much would the shipping cost ? And actually though I am low on money, I got stuff. Post a wish list.   Stuff? LOL, I've got too much stuff! Trying to winnow through the collection, not add to it. The only things I actively collect now are vintage HO slot cars. Silly, but it makes me feel a bit like a kid again just looking at them. My whole collection fits in a box the size of a toaster oven. I've given away a bunch of restored vintage radios, tube testers, clocks, etc., and loving the extra room in my basement. I've also got a couple of very early 1950s B&W TVs I've got to unload.   I don't know the cost to ship, but it's not terribly heavy and it's fairly compact. Since I know you'll actually make use of it and not flip it, I'll see if I can find a suitable box and pack it for you. I'll get you the dimensions and rough weight if you want to figure the shipping.   I had a couple of other inquiries but I put them on hold in case you want it. There's no rush. Contact my via email if you have any further questions.

Allodoxaphobia <knock_yourself_out@example.net>: Oct 08 05:13PM On Mon, 8 Oct 2018 08:26:24 -0700, John Robertson wrote: > fix it - botched it up, then sent it back to Amazon for a refund. The > seller didn't bother to test or it simply was repacked in the Amazon > warehouse for reshipment.   My take? ...and I've seen such crappy "rework" in never-been-opened-since-the-factory communist chinese junk before. It's post-test fail rework done in the factory -- by the lowest skilled folks on the totem pole. "Get it working just Good Enough to ship it."   Jonesy -- Marvin L Jones | Marvin | W3DHJ.net | linux 38.238N 104.547W | @ jonz.net | Jonesy | FreeBSD * Killfiling google & XXXXbanter.com: jonz.net/ng.htm

John Robertson <spam@flippers.com>: Oct 08 11:00AM -0700 On 2018/10/08 10:13 AM, Allodoxaphobia wrote: > factory -- by the lowest skilled folks on the totem pole. > "Get it working just Good Enough to ship it."   > Jonesy   Well, can't say I would argue with you.   Bought a LCD from Amazon, and while the monitor works fine the brick on a rope was bloody dangerous! The brick has no markings about approvals, so it went to recycling, and the power cord - that was a piece of work - a two prong (unapproved of course) plug on a two conductor line cord (no approval of course) ending with a computer style 3-prong plug for the brick (...).   The crap they are shipping will kill people.   Back in the late 40s and early 50s TVs in the USA would catch fire regularly. So the US Gov. gave UL some teeth and that stopped happening. Here in Canada CSA was already regulating electrical appliances (had been for years) and as I understand it there were few if any house fires caused by crappy manufacturing shortcuts.   The only real solution is international co-operation and standards that has to come to bear on all products as the general public has no idea about electrical/fire/food safety. I suspect a lot of children and adults have to die first though...   John ;-#(#   -- (Please post followups or tech inquiries to the USENET newsgroup) John's Jukes Ltd. MOVED to #7 - 3979 Marine Way, Burnaby, BC, Canada V5J 5E3 (604)872-5757 (Pinballs, Jukes, Video Games) www.flippers.com "Old pinballers never die, they just flip out."

Jeff Liebermann <jeffl@cruzio.com>: Oct 08 11:44AM -0700 >Like many things, if you know what you're doing you can get all >sorts of crap to work if necessary. >NT   When I was maybe 10-12 years old, I learned to solder making sewing machine attachments in my fathers petticoat factory. The attachments were necessary to make the elaborate folds and stiches found in all garments. Most were made from nickel-silver[1] sheet metal, which solders easily. The weapon of choice was a large block of copper attached to an iron rod and a wooden handle. Heat was provided by a natural gas burner: <https://www.slateroofwarehouse.com/Johnson_Bench_Furnace.html> Getting the temperature right was done by watching how the solder flowed when touched to the tip. Tip cleaner was a block of sal ammoniac. Flux was cocktail of various acids. We used different solders, but mostly very expensive silver solder because of the strength.   In late Jr High Skool, I was introduced to electronic soldering. Of course, I tried to handle a soldering pencil as if it was a block of copper on a stick, and destroyed everything I touched. It took a while to adjust to a smaller soldering iron. My parents bought me an Ungar soldering pencil, which was the best soldering iron of the day. No temp control, no thermostat, but good enough for what I was doing. I eventually collected an assortment of wood burners, real soldering irons, and home made contrivances on the assumption that if I needed a specific temperature, I would also need a different soldering iron.   One of my home made irons used a 16 penny nail as a soldering tip. The solder wouldn't stick to the tip, so I nickel plated most of the tip. That worked. I eventually discovered that mild steel did not burn up as quickly as high carbon drill rods. Iron would have worked better, but I didn't think of trying it.   During the late 1960's, I was a regular visitor to the various electronic surplus stores in Los Angeles and Silicon Valley. Among my purchases was a large box of broken Weller WTCPT bases, irons, cords, etc. Something like these: <https://www.google.com/search?q=weller+wtcpt&tbm=isch> Over the years, I've repaired or rebuilt 20-30 such soldering stations, some of which I still use today. Eventually, I'll run out of repair parts and will need to buy something better.     [1] 60% copper, 20% nickel, 20% zinc and no silver. <https://en.wikipedia.org/wiki/Nickel_silver> -- 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

"jfeng@my-deja.com" <jfeng@my-deja.com>: Oct 08 12:34PM -0700 > Yep - sorry. 37/63 lead-to-tin. Early AM post, and not quite awake.   > Peter Wieck > Melrose Park, PA Maybe you had the 2N3773 on your mind, which is almost equivalent to the 2N3772.

Ralph Mowery <rmowery28146@earthlink.net>: Oct 08 05:17PM -0400 In article <1i6nrdti83ho84792e08pf893p6ghvrpgn@4ax.com>, jeffl@cruzio.com says... > Over the years, I've repaired or rebuilt 20-30 such soldering > stations, some of which I still use today. Eventually, I'll run out > of repair parts and will need to buy something better.   I have one similar to those. It is an adjustable temperature. The temperature seems to be stable,but the readout is blank. Have not been able to find a schematic for that particular one on the internet. Found some similar,but not the one I have.   I seldom use it any more. I have one of the inexpensive China $ 70 hot air and iron stations. It heats up very fast and is good enough for my hobby work. I doubt it would hold up for daily use. I would buy the much higher dollar unit if I was in the repair business.

"pfjw@aol.com" <peterwieck33@gmail.com>: Oct 09 04:03AM -0700 > Maybe you had the 2N3773 on your mind, which is almost equivalent to the 2N3772.   They are pretty much interchangeable in most applications. I prefer the 2N3772 - I have never had a failure, and I have reliable sources. I have come across a number of counterfeit 73s. This is a hobby for me, so coming across even one counterfeit is remarkable, much less 3 out of 5.   Peter Wieck Melrose Park, PA

tabbypurr@gmail.com: Oct 09 05:57AM -0700 On Monday, 8 October 2018 19:44:54 UTC+1, Jeff Liebermann wrote: > of repair parts and will need to buy something better.   > [1] 60% copper, 20% nickel, 20% zinc and no silver. > <https://en.wikipedia.org/wiki/Nickel_silver>   It's not just soldering where one can scrape the barrel. I remember using 3 filament bulbs in lieu of a multimeter. The TV got fixed. What I can't remember is why I didn't have a multimeter there.     NT

Phil Allison <pallison49@gmail.com>: Oct 08 04:34PM -0700 Ralph Mowery wrote:   > I am thinking that in this circuit I could take an output across just > one of the capacitors as it seems to be a halfwave circuit with added > components. Will this work     ** Yep.   Symmetrical loading is not required.     ..... Phil

jurb6006@gmail.com: Oct 08 04:49PM -0700 About the easiest way to do it is thus -   Version 4 SHEET 1 880 680 WIRE 352 64 208 64 WIRE 608 64 352 64 WIRE 688 64 608 64 WIRE 208 96 208 64 WIRE 352 96 352 64 WIRE 608 96 608 64 WIRE 208 176 208 160 WIRE 208 176 -16 176 WIRE 208 208 208 176 WIRE 352 208 352 160 WIRE 416 208 352 208 WIRE 560 208 496 208 WIRE 32 240 -16 240 WIRE 32 304 32 240 WIRE 416 304 416 208 WIRE 416 304 32 304 WIRE 208 320 208 272 WIRE 352 320 352 272 WIRE 352 320 208 320 WIRE 560 320 560 272 WIRE 560 320 352 320 WIRE 608 320 608 160 WIRE 608 320 560 320 WIRE 688 320 608 320 SYMBOL diode 224 272 R180 WINDOW 0 24 64 Left 2 WINDOW 3 24 0 Left 2 SYMATTR InstName D1 SYMBOL diode 368 272 R180 WINDOW 0 24 64 Left 2 WINDOW 3 24 0 Left 2 SYMATTR InstName D2 SYMBOL diode 368 160 R180 WINDOW 0 24 64 Left 2 WINDOW 3 24 0 Left 2 SYMATTR InstName D3 SYMBOL diode 224 160 R180 WINDOW 0 24 64 Left 2 WINDOW 3 24 0 Left 2 SYMATTR InstName D4 SYMBOL sw 512 208 R90 SYMATTR InstName S1 SYMBOL cap 544 208 R0 SYMATTR InstName C1 SYMBOL cap 592 96 R0 SYMATTR InstName C2 TEXT -128 208 Left 2 ;AC input TEXT 680 192 Left 2 ;DC output TEXT 368 136 Left 2 ;closed for doubler TEXT 40 288 Left 2 ;neutral TEXT 40 152 Left 2 ;hot   Only 2 caps and 4 diodes.

Phil Allison <pallison49@gmail.com>: Oct 08 07:02PM -0700 Phil Allison wrote:   > > I am thinking that in this circuit I could take an output across just > > one of the capacitors as it seems to be a halfwave circuit with added > > components. Will this work   https://www.daenotes.com/sites/default/files/article-images/full-wave-voltage-doubler.png   > ** Yep.   > Symmetrical loading is not required.   ** However, transformers have limited ability to supply current into a half wave load - in some cases only 10% of the rated current before unacceptable core magnetisation offset occurs.   The primary current soon becomes large & very asymmetrical, accompanied by a growling noise and overheating.     .... Phil   .... Phil

Ralph Mowery <rmowery28146@earthlink.net>: Oct 08 11:14PM -0400 In article <e4a3d6d1-78d8-4740-a16e-7a631a1c952c@googlegroups.com>, jurb6006@gmail.com says... > WIRE 608 64 352 64 > WIRE 688 64 608 64 > WI   What is the program that uses this format ?

jurb6006@gmail.com: Oct 08 10:09PM -0700 >"What is the program that uses this format ? "   LTSpice 4   There is a newer version but hardly anyone has it, I don't remember why. You might need the newer version on a 64 bit OS.

pit <f6ceedb9c75b52f7fcc0a55cf0cfbf5d_1115@example.com>: Oct 08 11:37PM responding to http://www.electrondepot.com/repair/icepower-200asc-amp-module-165648-.htm , pit wrote: I repaired my amp with a 1000PF 1KV ceramic cap. Like Gareth, my main fuse was blown and I also had to replace it.

"pfjw@aol.com" <peterwieck33@gmail.com>: Oct 08 11:42AM -0700 Mouser Electronics stocks 2N3772 output transistors from ON Semi-conductor. They run about US$3.50 each in lots of 10 (which will assure you of matching at least four, if not more), and shipping across the Ocean is not so much as to preclude that option.   https://www.mouser.com/_/?Keyword=2N3772G   That is a high-powered TO3-case PNP output transistor that is capable of 60+ watts in PP. I will retrofit them anywhere appropriate, and they are very nearly a drop-in replacement for the 2N3055 or equivalent. I state 'very nearly' as some devices may require a bias adjustment.   Note that in my experience, one or another of the driver pair often fails and takes the outputs with it, or the outputs fail and take a driver-or-two. Do also check for failed diodes - that failure may be invisible - and failed caps. As previously noted, comparing channel-to-channel is key.   Yes, that HK Series is worth the trouble.   Peter Wieck Melrose Park, PA

Ralph Mowery <rmowery28146@earthlink.net>: Oct 08 04:48PM -0400 In article <a1a08435-175d-46c9-bd56-0b538750fb51@googlegroups.com>, peterwieck33@gmail.com says...   > Yes, that HK Series is worth the trouble.   > Peter Wieck > Melrose Park, PA   They are NPN , not PNP.   OUtside of that the 2n3771, 2n3772 and 2n3773 are all similar. They are a much higher power than the 2n3055 and I also use them to replace the 2n3055 in most power supply circuits.

jurb6006@gmail.com: Oct 08 04:21PM -0700 >"Never saw one, but I did qualify my statement by saying that anything is possible. "   Well, I have repaired thousands upon thousands and actually have seen them go that way about a half dozen times. It is not common to say the least.   One weird time I had a connection to the base of a horizontal output, IIRC it was an NAP, and that SOB oscillated on its own ! I am initially looking for a sync problem and it was nothing of the sort. Miller effect on steroids or whatever, I mean how the hell did... ? What's more is it was only a few hundred Hz off, and high not low.   >"Yikes. I remember a Hitachi receiver in the shop back in the early 80s that would destroy speakers whenever it wanted to. Play nice, short loud hum, speaker smoke. "   I had a Sansui 8900 do that due to a transistor socket. Blew both woofers in one of the guy's EPIs. I sold him a pair and found out that the polarity of the ones I had were reversed from the original. I mean red to red, black to black, out of phase.

jurb6006@gmail.com: Oct 08 04:36PM -0700 >"Note that in my experience, one or another of the driver pair often fails and takes the outputs with it, or the outputs fail and take a driver-or-two."   That is the reason for the procedure I described.   The 2N3773 is better in another way, the gain curve. The 3773 still has 35 HFE at 10 amps, while a 3055 drops to 10. At 5 amps the 3773 is 60 and the 3055 is 30. Both of them start around 100 or so at like a half amp.   >"Yes, that HK Series is worth the trouble. "   Absolutely, but I recommend speaker fuses. One good trick to keep the fuses form introducing distortion at high level low frequencies (this is not audiopholery, it is measurable) is to make a high value bipolar out of like 2 8,200 uFs in series +to+ and put it across the fuse. That only DC or very low frequencies will blow it. For this amp all you would need is 35 volt units.

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