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oldschool@tubes.com: Jan 29 02:32PM -0600 I want to re-cap an old tube type shortwave radio. I dont mind using plastic coated caps to replace the old paper-wax ones in the circuit. (Meaning the smallish ones, such as .05 .02 .001, etc.)   However, it seems that no one sells the multi-part electrolytic capacitors anymore. Particularly the ones on aluminum containers that were mounted on the chassis. Those used to be very common on all old TVs, radios, and other stuff. Normally, they came with 2, 3, or 4, caps inside one container. (I never saw more than 4). Something like 50mf 450v 30mf 300v 10mf 150v was common. And not only the aluminum chassis mounted ones, but many of the old (American Five) sets (5 tubes) had a wax coated multi-part electrolytic capacitor, which went below the chassis and was mounted by a strap around the cap body, and had a black wire (GND), and a different color wire for each internal cap.   I like to restore this stuff to look original, as well as having to consider that some of these devices dont have much spare space under the chassis, to add individual caps.   I have checked both real stores and online vendors and no one seems to sell these multi-part electrolytic capacitors anymore. Yes, I did run across a few "OLD STOCK" caps, but I would assume that they deteriorate almost as much as those inside a circuit, from aging. So, I'll avoid them.   Does anyone know of any source for the multi-part electrolytic capacitors which are still made to fit these vintage tube devices?   One other thing. I am not finding any 50-50 or 60-40 lead tin rosin core solder anymore. At least not in the stores. I do not plan to serve anyone dinner on the underside of a chassis, so I'm not worried about getting lead poisoning. But apparently the government must think we eat off of our electronics and have banned the old lead based solder.   Since I will be removing old caps, soldered with lead-tin solder, shouldn't I be using lead-tin solder to replace the parts? Or will the new solder (whatever it's made of), mix properly with the old lead based stuff? (I dont want to create some sort of dialectric corrosion issues). [Even with a desoldering bulb and wicking, not 100% of the lead is ever removed]. Not to mention that I have heard that some (or all) of these new solders require a lot more heat, which can damage the components while soldering.   I have not worked on tube equipment in years, and I am looking forward to this project. But things sure have changed since the time I played around with these radios years ago (1960s - 70s). I gave up my electronics hobby when semiconductors took over, because they are just not as much fun to work on and too difficult to repair. Maybe working on some tube equipment will make me feel young again. :)

dplatt@coop.radagast.org (Dave Platt): Jan 29 02:03PM -0800 In article <02is8c9u88l40h63st3fhjbc8h4172jisc@4ax.com>,   >I like to restore this stuff to look original, as well as having to >consider that some of these devices dont have much spare space under the >chassis, to add individual caps.   What a lot of people in your situation do, these days, is temporarily remove the old cap-can, carefully gut it, and install several smaller modern capacitors inside the shell, connecting them to the appropriate lugs on the bottom terminal disc. Using modern caps, and a bit of sleeving on the leads, it's usually possible to fit the necessary individual parts into the shell.   You can then reinstall the Wolves In Cheap Clothing capacitor-set in its original location. Cosmetically it will look just like the original; electrically it will probably be quite a bit superior to the original.   You might be able to do the same thing with the wax-coated multicap... or, if its case is already "gone bad" you can probably make a reasonable look-alike using a cardboard sleeve over a set of modern caps, and (if you insist on original appearance) dip it in wax or varnish.

Phil Allison <pallison49@gmail.com>: Jan 29 06:41PM -0800 > were mounted on the chassis. Those used to be very common on all old > TVs, radios, and other stuff. Normally, they came with 2, 3, or 4, caps > inside one container. (I never saw more than 4).   ** Not made anymore by anyone.   EXCEPT for some double types with brands like F&T, ARS and K&D.   LCR used to make them too but when out of business about 10 years ago.   You will see them all on eBay.     FYI   I have come across new looking triple types that were sold for use in old Fender amps:   https://www.talkbass.com/attachments/cap_can-jpg.985203/   Don't buy them, they are 50+ year old caps that are all faulty.       .... Phil

Ralph Mowery <rmowery28146@earthlink.net>: Jan 29 11:17PM -0500 In article <02is8c9u88l40h63st3fhjbc8h4172jisc@4ax.com>, oldschool@tubes.com says... > electronics hobby when semiconductors took over, because they are just > not as much fun to work on and too difficult to repair. Maybe working on > some tube equipment will make me feel young again. :)   Look here for the capacitors you want.   https://hayseedhamfest.com/   YOu should be able to find the 60/40 solder from places in the US.If in anoter country, I don't know.   Ebay is full of the 60/40 and 63/37 solder.   Mouser.com has some at about $45 per pound spool   The newer stuff will mix ok with the old for the tube size equipment. Just takes more heat to melt the newer stuff. I don't use the lead free on anything. No work for pay,as I am just doing electronic work for myself.

"Dave M" <dgminala@mediacombb.net>: Jan 29 10:39PM -0600 Those multi-section capacitors are quickly becoming extinct. There are a few vendors that still cater to those who resotore antique electronics. Here are a few that I have used in the past. https://hayseedhamfest.com/ http://www.justradios.com/ https://www.tubesandmore.com/products/capacitors https://vacuumtubesinc.com/ http://store.triodestore.com/ http://www.oldradioparts.com/ http://www.grillecloth.com/other/parts.php   There are probably more that I haven't seen or heard of. There have been several sites that have shut down, likely because of the owners' health or lack of buisiness. There used to be a guy online who actually rebuilt the old multi-section capacitors. He opened the aluminum case, removed the old capacitor guts and replaced the sections with new, individual capacitors and resealed the case. He did a pretty good job; I used his service a couple of times, but his health caused him to close the business. you're correct about the "old stock" parts. the electrolytics will have to be reformed before putting them to work in a real circuit. If they're not too far gone, reforming will get a lot of life out of them. If you have no other choice, you have a good chance of bringing them back to life.   I use the old 63/37 tin/lead solder. Not cheap any more, but still available. No reason to go lead-free in the old equipment. http://www.mcmelectronics.com/browse/Lead-Alloy/0000001207 http://www.allelectronics.com/category/570/solder-accessories/1.html http://www.skycraftsurplus.com/search.aspx?find=solder http://www.mpja.com/Solder-Accessories/products/348/   Good luck in your hobby. Not many of us old tube guys around any more.   Cheers, Dave M

Chris Jones <lugnut808@spam.yahoo.com>: Jan 30 05:27PM +1100 > removed]. Not to mention that I have heard that some (or all) of these > new solders require a lot more heat, which can damage the components > while soldering.   You can still buy leaded solder, even in Europe where it is not allowed in new electronics that is sold, but can still legally be used to repair things that were built before 2006. You can also use it to make new things in Europe if you do not "place them on the market".   The solder with 60% lead is not even very nice to use, because it spends a lot of time in a "mushy" state as it is cooling. I think they only used 60% lead in old appliances because lead is cheaper than tin. The eutectic alloy with 37% lead is much better because it goes from fully liquid to being fully solid over a small range of temperature, but is slightly more expensive due to the higher price of tin.   Some of the lead-free solders are actually not bad to use, for example 96SC alloy from Multicore. The melting point is a bit higher than tin-lead eutectic but probably not much different from the 60% lead alloy that you wanted. The high melting point would only really be a problem if you are desoldering components from plated-through holes in a multilayer board with several ground planes buried within it, and that sounds unlikely for your vintage electronics. The only problem that I have with the 96SC alloy is that it is expensive, perhaps partly due to the 3.8% silver content.   The area around the wet sponge used for cleaning the soldering iron usually gets covered in tiny solder particles and dust, that get on the carpet etc. When soldering at home the main risk is probably if you have a young child in your family of the age where they crawl on the floor eating dirt, and they eat some lead dust. A blood concentration of lead that is increased by 50 parts per billion is correlated with an IQ that is 10 to 20 points lower. If you do the calculations, 50 parts per billion is not much. http://oehha.ca.gov/media/goodmangilmanlead.pdf If you are working on old equipment then regardless of whether you use leaded solder wire or not, the solder droplets that end up on your sponge and on the bench around it will contain lead, so it is best to wipe it up carefully and keep it out of living areas of your house.

N_Cook <diverse@tcp.co.uk>: Jan 30 12:12PM > electronics hobby when semiconductors took over, because they are just > not as much fun to work on and too difficult to repair. Maybe working on > some tube equipment will make me feel young again. :)   Research the term "restuffing", I've done it a few times. Modern caps tend to be smaller volume and if you can find the right aspect ratio, can get 2 or 3 in a recycled can. Add insulation between the caps, removing the original contents can be messy and you might have to go for axial type caps and somtimes the new contents might protrude under the can

"pfjw@aol.com" <pfjw@aol.com>: Jan 30 04:39AM -0800 On Sunday, January 29, 2017 at 9:41:59 PM UTC-5, Phil Allison wrote: > olds...@tubes.com wrote:   > ** Not made anymore by anyone.   Most of the "popular" types of multi-section caps are still made for specific purposes.   http://www.tubes4hifi.com/ST70.htm about halfway down the page.   This is only one (1) example of such sources. There are a great many similar sources. I have seen such dedicated to brands like Zenith and Hallicrafters in the radio end of the hobby - and many more dedicated to the likes of McIntosh, Dynaco, Eico, Marantz and others. The downside is that they are NOT cheap, typically tens of multiples of the cost of individual caps.   That being written, NOS caps are as suspect as the one in your radio. Restuffing works nicely, is inexpensive and as you become more skilled at it, will be invisible as well as far less costly.   Peter Wieck Melrose Park, PA

Phil Allison <pallison49@gmail.com>: Jan 30 06:10AM -0800 > > ** Not made anymore by anyone.   > Most of the "popular" types of multi-section caps are still made for specific purposes.   > http://www.tubes4hifi.com/ST70.htm about halfway down the page.   ** The rest of my post you fucking SNIPPED details exactly that brand of electro cap - complete with a very clear pic.   And it points out the suppliers are *criminal fraudsters*.   FFS, you retarded fucking asshole - READ what is fucking posted ~!!~!!       > Peter Wieck > Melrose Park, PA   ** Must be right next fucking La La Land.   Piss the fuck off you senile, useless fucking retard.   And I mean that most sincere.       .... Phil

"pfjw@aol.com" <pfjw@aol.com>: Jan 30 06:19AM -0800 You need to take a Chill Pill.   VTA & Bob Latino have been around for many years, stand behind their products and sell good stuff. The other dedicated suppliers are also of long and good standing including a few that I have meet personally and actually observed and tested their products.   Point being that multi-section caps are still in production, albeit limited to mostly the highest-volume values and types, or for the most expensive (and popular) equipment. But, for all that, still in production.   It must be very easy from a cave in Australia to spit out invective supported by anecdotes of doubtful veracity - if even that much. Were you more available, I am fairly sure that some of your fans would have at the very least adjusted your attitude, if not cleaned your proverbial clock for you. I guess you are that 3-year old - if she can't see it, it does not exist.   https://www.die-wuestens.de/dindex.htm?/k8.htm   Another one.   Peter Wieck Melrose Park, PA

Phil Allison <pallison49@gmail.com>: Jan 30 06:41AM -0800 > You need to take a Chill Pill.   ** You nee a fucking bullet in the head.     > VTA & Bob Latino have been around for many years,     * So fucking, stinking what ???   The "CE Manufacturing" brand electros on that page are a criminal FRAUD.   Bob Latino is profiting from the SCAM, so is just as bad as them.   I have seen them personal,y so I fucking know.   YOU FUCKING HAVE NOT !!!!       > Point being that multi-section caps are still in production,     ** And I clearly pointed out the very few, dual ones that *really were*.   But you snipped them out of sight too, you stupid, fucking senile ASSHOLE.       > It must be very easy from a cave in Australia ...   ** What shit hole do you live in fucked, a septic tank ?       FYI to all:     The Peter Wieck troll is one of the worst, lying nut cases seen on usenet over the last 15 to 20 years - probably longer.   The retard has no ide how retarded he is so it might seem cruel to abuse him, I know.   But how the hell else do you shut dangerous FUCKING IDIOTS like him up ???         .... Phil

"pfjw@aol.com" <pfjw@aol.com>: Jan 30 06:48AM -0800 Coming from you, this makes me quietly proud! Yet, as it happens, I do feel sorry for you as, clearly, your meds are failing again.   Peter Wieck Melrose Park, PA

oldschool@tubes.com: Jan 29 03:01PM -0600 On Thu, 05 Jan 2017 10:04:58 -0800, Jeff Liebermann <jeffl@cruzio.com> wrote:   >transistor will dissipate considerable heat at high loads.   >Sounds like too much work. I'll see if can find one in my junk pile. >I've been hoarding germanium devices for years for use in repairs.   I have not heard about germanium in years. When I played around with old tube stuff in the 60s - 70s, I remember germanium diodes were fairly common. I never ran across a germanium transistor.   Reading this thread made me question what germanium really is, and I read the following article (good article). I know it was used to make the FIRST semiconductors, I never knew much more about it. It appears it's a costly elemental material.   Here are a few clips from that article.   [Quote]   From: https://en.wikipedia.org/wiki/Germanium   Germanium "metal" (isolated germanium) is used as a semiconductor in transistors and various other electronic devices. Historically, the first decade of semiconductor electronics was based entirely on germanium. Today, the amount of germanium produced for semiconductor electronics is one fiftieth the amount of ultra-high purity silicon produced for the same. Presently, the major end uses are fibre-optic systems, infrared optics, solar cell applications, and light-emitting diodes (LEDs). Germanium compounds are also used for polymerization catalysts and have most recently found use in the production of nanowires. This element forms a large number of organometallic compounds, such as tetraethylgermane, useful in organometallic chemistry.   - Germanium differs from silicon in that the supply is limited by the availability of exploitable sources, while the supply of silicon is limited only by production capacity since silicon comes from ordinary sand and quartz. While silicon could be bought in 1998 for less than $10 per kg, the price of germanium was almost $800 per kg.   [End Quote]

"Benderthe.evilrobot" <Benderthe.evilrobot@virginmedia.com>: Jan 29 09:32PM <oldschool@tubes.com> wrote in message news:2gls8c9v6rniulp4et8n6ecvu5stq491ri@4ax.com... > read the following article (good article). I know it was used to make > the FIRST semiconductors, I never knew much more about it. > It appears it's a costly elemental material.   Apparently it was refined from flue dust where a specific type of coal was used.   Not difficult to see how it might be hard to come by nowadays.

Jeff Liebermann <jeffl@cruzio.com>: Jan 29 02:10PM -0800 >I have not heard about germanium in years. When I played around with old >tube stuff in the 60s - 70s, I remember germanium diodes were fairly >common. I never ran across a germanium transistor.   Germanium transistors were very common in the 1960's. For example, I was selling all germanium Motorola pagers and partly germanium mobile radios at the time. All of the old vibrator power supply to transistor conversions used germanium power transistors. Most of the AM car radios were germanium.   Germanium is not dead today. There are SiGe devices that use the best properties of both materials to good advantage. <https://en.wikipedia.org/wiki/Silicon-germanium>   Germanium is also the preferred material for Infrared lenses. <http://www.iiviinfrared.com/Optical-Materials/ge.html>   >While silicon could be bought in 1998 for less than $10 >per kg, the price of germanium was almost $800 per kg.   Yep. Germanium is expensive. Price at the end of 2015 was $1,760/kg ($800/lb): <https://minerals.usgs.gov/minerals/pubs/commodity/germanium/mcs-2016-germa.pdf>   -- 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

MJC <gravity@mjcoon.plus.com>: Jan 29 10:31PM In article <3btjA.131757$MU7.29082@fx18.am4>, Benderthe.evilrobot@virginmedia.com says...   > <oldschool@tubes.com> wrote in message > news:2gls8c9v6rniulp4et8n6ecvu5stq491ri@4ax.com... > > I have not heard about germanium in years. When I played around with old > > read the following article (good article). I know it was used to make > > the FIRST semiconductors, I never knew much more about it. > > It appears it's a costly elemental material.   Back in the early 1960s I conducted an undergraduate/apprentice training project to build a quartz clock. I think every transistor was germanium.   To divide the crystal frequency by multiple decades it used locked multivibrators (no digital circuits whatsoever, though my employer made computers). Anyone seen a circuit like this: https://onedrive.live.com/? cid=72C9DE495D23AD02&id=72C9DE495D23AD02%215482&parId=72C9DE495D23AD02% 215481&o=OneUp ?   It was my very own design; I still have the circuit value calculations!   Mike.

jurb6006@gmail.com: Jan 30 01:46AM -0800 Would have liked to see that but onedrive doesn't seem to like my computer. I am sure some sort of download will fix everything but they can stick that where it is sure not to get a sunburn.

MJC <gravity@mjcoon.plus.com>: Jan 30 11:21AM In article <067ebd37-fe5a-475d-b034-62b5b9a1cb19@googlegroups.com>, jurb6006@gmail.com says...   > Would have liked to see that but onedrive doesn't seem to like my computer. I am sure some sort of download will fix everything but they can stick that where it is sure not to get a sunburn.   Thanks for that; I'm not good at "sharing"! It should just have been a URL link. Please try this instead: <https://goo.gl/photos/cZRDRY1JB3vTTr2F9>   Mike.

"Newgene McMensa" <newgene.mcmensaREMOVE@gREMOVEmail.com>: Jan 29 09:21PM -0800 This is a great story for late night or a rainy day.... Anyone who grew up tinkering with gadgets has got to listen to this story by Steve Gibson. He telling a great story about making a device to keep a barking dog from pestering him on his walks home from school. Reminds me of a Tom Sawyer or Our Gang type story.   SN 592: The Portable Dog Killer. Steve Gibson Episode 248. Hosts: Steve Gibson and Leo Laporte   Video https://www.youtube.com/watch?v=8Glft9CQ-5s (2016)   Site, A/V, transcripts https://twit.tv/shows/security-now/episodes/248 (original 2010) https://twit.tv/shows/security-now/episodes/592 (same but adds a good intro 2016)   Audio Files http://twit.cachefly.net/audio/sn/sn0592/sn0248.mp3 (2010) http://twit.cachefly.net/audio/sn/sn0592/sn0592.mp3 (2016)

Ralph Mowery <rmowery28146@earthlink.net>: Jan 29 11:13AM -0500 In article <b1686725-bdf1-41ea-ac58-e71b1db520c0@googlegroups.com>, pfjw@aol.com says...   > And the aforementioned meter. In my traveling kit (Kutztown twice per year, and when 'in the field', I keep a very vintage Radio Shack Japanese VOM, and the AnaTek ESR meter.   > Paying a premium for my meters to get reliability, predictability and function is by no means any sort of rip-off. I have been known to pay $40 for a pair of box-joint Linesman Pliers (ChannelLock) rather than $8.99 for a similar-in-size piece of Chinese Junque.   > Good (new) tools are not cheap. Cheap (new) tools are not good.   You should have looked at this persons comparison:   https://www.youtube.com/watch?v=HbHGpA1jrJE   The ripoff by Peak is that they could have combined two devices in one meter as it is mostly software. They chose to only enable passive or active devices to they can sell two boxes and double the profit.   I agree it is good to pay more for a quality instrument, but lately there seems to be some very good quality items comming from China, especially if you look at the price of them. I just bought a 200 MHz scope and a function generator made in China from a company in the US. They work very well.   Bein a ham radio operator I have bought some of the trnsceivers from China and have contacts with many more. Some of them work very well and a lot less then the Japan vesions. There are also some junk copies of the Japan radios that do not work well at all.

"Benderthe.evilrobot" <Benderthe.evilrobot@virginmedia.com>: Jan 29 09:29PM <pfjw@aol.com> wrote in message news:c9a30904-8a86-4373-8694-a4a81a2f31db@googlegroups.com...   > I also use the Peak Atlas device. Paid for itself the day it arrived > (under the Tree on Christmas Day) with the smile on the kids' faces when I > opened it - and many times since in actual use.   I actually won mine for letter of the month in a hobby magazine - but I was trying to divert funds into a kitty to buy one anyway.

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