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tubeguy@myshop.com: Jan 14 09:24PM -0600 I remember a lot of old transformers, particularly the power transformers on the old TV sets, were coated with tar. It was not a real problem, but was kind of ugly, particularly when the wires had tar all over them.   What was the purpose for the tar? My guess was to eliminate chattering of the steel laminations. Yet, it seems the practice of using tar vanished for the most part in the 70s and later. Yet I have not seen any untarred modern transformers chatter......   I will add to this, that the most chattering I have heard from transformers are the small ones which do NOT have bolts going thru the core, such as filament transformers and doorbell transformers. Several times over the years I have had people ask me why there is a noisy sound in their basement and it never fails, it's the doorbell transformer.   This could often be fixed by squeezing the outer metal piece against the laminations, and applying something like laquer or silicone caulk. However, for the small price they cost, I usually just replaced them with a new one.

MOP CAP <email@domain.com>: Jan 15 12:55AM -0800 > laminations, and applying something like laquer or silicone caulk. > However, for the small price they cost, I usually just replaced them > with a new one.   You are most likley correct. As for tar, it was cheap and epoxy hadn't been invented yet. CP

tabbypurr@gmail.com: Jan 15 03:36AM -0800 > laminations, and applying something like laquer or silicone caulk. > However, for the small price they cost, I usually just replaced them > with a new one.   Modern transformers use clear stuff for the same purpose. It stops noises & holds the windings etc in place.     NT

Look165 <look165@numericable.fr>: Jan 15 01:08PM +0100 I've been working for transformers. Telecoms ones, but it's the same.   Once, winded and assembled, the pieces were put in a resin we call "jaja" in France. And then put in an under-pressurized "bubble room" for completing the process. When there was no more bubbles, the process was over.   Resin (or tar) is there for noise suppression, mechanical fixing of the windings and insulation improvement.

Tim R <timothy42b@aol.com>: Jan 15 05:33AM -0800 People put tar on airgun springs to remove noise and smooth out firing.   That's not the ideal way, but that requires precisely fitted spring guides adjusted for the individual airgun, and that doesn't happen in manufacturing.

jurb6006@gmail.com: Jan 14 07:45PM -0800 >"I won't argue your results, but with 35 years of repairing audio gear, I have not seen one yet that has that property. The in/out label on any gear is usually for that particular unit. The same exists on tape machines. There are input and output jacks there as well. The "output" jack on the tape should be activated when the tape is in play mode, thus is an output. "   That has not been my experience. In most amps the tape output is pretty much at the output of the input selector, or in the case of a Yamaha for example, form another separate selector. As such it can be backfed.   If it is buffered or even resistor isolated that will not work so well, but it seems the engineers decided that the low output impedance as worth it to keep the noise down. As such, not only can it be backfed, it can also be shorted by the wrong thing connected and cause no output. I got this DCD Pro CD player, commercial, like DJ model. I had it temporarily hooked up wrong because I couldn't really see in the back, it was going IN to the tape OUT. Well when the CD player was shut off it apparently shorts the outputs and that resulted in no sound from any source.   In another case I had a VHS HIFI, a Sanyo VCR-7200 that when turned off got non linear at the record INPUTS. It caused severe distortion unless it was turned on. It is easy to figure out why, the input stage was probably diode protected against overvoltage and when the power supply dropped, the shunting was to zero volts.   It is a piece of wire, the "current" can go both ways.   I didn't mention it before I think, but some of those units used a TC9164 or something as a selector chip and those did go bad. I had to change a bunch of them back when. That was how they were - the tape output was the only "input" that would work.   What I don't remember is if those chips fed a CMOS switch set or had it onboard. Like 4066s, or the cheaper one, 4016 ? Whatever.   I could probably find a print and find out but why don't you just to it ? Right from Google you got Electrotanya, and then there is hifiengine and hifimanuals. You need a membership to the latter two but they don't charge, they don't spam or any of that. I got nothing but good to say about those sites.   If you need the TC9164 they are out there. I have just Googled it and it seems they do have the actual switches onboard.   I know that amp is considered BFC by audiophiles but that series of amps is not bad. The circutry is fine, low distortion, all that. Anything the audiophools don't hear in it is their own problem. The only problem is they are underbuilt, for someone like me. I mean I will work it into 2.3 ohms n shit, they don't like that, they get too hot. That's why I don't use one, but for normal human beings the are OK.

jurb6006@gmail.com: Jan 14 07:46PM -0800 >"But I'm wondering if the tape mon connections are simply labelled "in" and "out", or if they're preceded by "connect to"... "   I can't stand shit like that. Just say it, output or input, not what you connect it to.

tubeguy@myshop.com: Jan 14 09:25PM -0600 On Fri, 11 Jan 2019 15:21:54 -0800 (PST), whit3rd <whit3rd@gmail.com> wrote:     >Oh, then the 'easiest' solution I'm aware of is a pogo pin soldered in a BNC >fitting, and a lathe-job threaded tube, 3/8-27 to 38-32, to mate the threads.   >I'm not sure I've ever encountered 3/8-27, but I have taps for 3/8-24./ -26. /-32   Pogo pin???? What's that?

tubeguy@myshop.com: Jan 14 09:25PM -0600 On Fri, 11 Jan 2019 15:37:36 -0800 (PST), whit3rd <whit3rd@gmail.com> wrote:     >> The Amphenol button connector is 3/8-27 pitch.   >Is this about the connector depicte, I d here <https://archive.org/details/Amphenol/page/n5> >at the top left of page M-6 ?   Yes.   I would have been more descriptive in my original posting, but it seems there are numerous names for them, and not a standard "name". But most people seem to understand "vintage ONE pin MIC connector".   It seems a lot of people hate them, and want to replace all of them with BNC. Personally, I like those oldies. Sure it takes a few seconds longer to screw them on, but they worked well, and under normal use, they were not changed all that often. Plus, they were versatile, since they were both male and female, by using or removing the "ring". That alone was an ingenious invention.   I may be wrong, but I believe they were originally designed for microphone use, and later adapted for test gear connections. I can see why they were later replaced by modern microphone connectors, having 3 connections, since the microphones needed better shielding and impedance matching. But for use on test equip. they still work great.   The hardest part these days, is finding the connectors ends at a reasonable price. Someone always has them on ebay, but usually at ridiculous prices. From my understanding, they are no longer manufactured, so all that exist are NOS. Fortunately I was able to buy 3 of them awhile back at a fair price and they were new in the package. I now wish I had gotten a few more from the seller..... I think he had around 10 of them total.

"Dogma" <1011001@0010010001.com>: Jan 14 07:36PM -0600 > Marvin L Jones | Marvin | W3DHJ.net | linux > 38.238N 104.547W | @ jonz.net | Jonesy | FreeBSD > * Killfiling google & XXXXbanter.com: jonz.net/ng.htm   The web pages started working early today. I was finally able to buy credits. The unlocker is having problems connecting to the internet, so I don't know when the Netgear hotspot will unlock.   Verizon has an unlimited plan for hotspots I'd like to try , that's supposed to be better than than the phone plan.

Fox's Mercantile <jdangus@att.net>: Jan 14 10:50AM -0600 >> etc...   > You won't do very well in life with that attitude.   > NT   Actually, I do quite well with that attitude. I buy things that work.   That way I don't have to waste my time and money playing "Mr. Wizard."         -- "I am a river to my people." Jeff-1.0 WA6FWi http:foxsmercantile.com

Jeff Liebermann <jeffl@cruzio.com>: Jan 14 10:10AM -0800 On Mon, 14 Jan 2019 07:02:04 -0800 (PST), bruce2bowser@gmail.com wrote:   >on the container's label just isn't what you want. Go to a trusted >computer or parts retailer and specifically ask for 'parts cleaner', >'head cleaner' .. etc.   Three problems: 1. I don't know of any computer or parts retailer that I would trust. 2. I once asked for "head cleaner" and was presented with a bottle of shampoo. 3. Everyone reads the label only after the product has been consumed.   -- 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

tabbypurr@gmail.com: Jan 14 11:38AM -0800 On Monday, 14 January 2019 16:51:05 UTC, Fox's Mercantile wrote: > I buy things that work.   > That way I don't have to waste my time and money playing "Mr. > Wizard."   I've learnt something today. I wasn't aware that paying a tenth the price for a better & entirely customisable product was a form of wizardry. Nor that it wasted time or money.   Retail concoctions often work, but often not adequately IME. Really it never ceases to amaze me what people pay for mostly water.     NT

"pfjw@aol.com" <peterwieck33@gmail.com>: Jan 14 11:46AM -0800 What it comes down to is that there are not a lot of different cleaning materials out there. There are, however, very nearly infinite variations on a very, very few themes. Nothing is magical. And nothing is special in any meaningful way. There are companies that invest heavily in "proprietary" formula, some of which actually work well, and some of which do not. But every single one of them will start with what is most likely the same 20 or so basic materials. And nothing is secret. Do you really think that no other manufacturer has never dumped a drop of DeOxit into a gas chromatograph? Or a drop of Cramolin Red? Or any other solvent, chemical or material?   What is, more importantly, what is not in these magic formula is not magic. The Virgins that do the mixing only on Walpurgis Night are the stuff of legends, not fact-based. Nor do we have to be Mr. Wizard as we approach this. We need to understand some basic chemistry, understand the materials at hand and in use, and understand how any chemical reactions as may take place start, and more importantly, finish. Not a complicated process. We need to understand how chemical mix, what happens to the mix over time, and when applied, how they operate. Not a complicated process, either.   We have choices. Unlike Jeff, I am not in the fee-for-service aspect of the hobby. So, I do not have to warrant anything. Were I to, you bet that anything I used on my bench would be a supportable name-brand product designed for the use-at-hand. So, I may hand-mix a Cramolin-Red analog to my own needs. Or use some glacial ammonia to strip a really nasty part down to its bones. To me, the alternative is landfill - so "kill-or-cure" is not an idle statement.   But I do know my chemistry - at least as it applies to "heads" of various natures.   Peter Wieck Melrose Park, PA

Martin Gregorie <martin@mydomain.invalid>: Jan 14 08:32PM On Mon, 14 Jan 2019 10:10:38 -0800, Jeff Liebermann wrote:   > On Mon, 14 Jan 2019 07:02:04 -0800 (PST), bruce2bowser@gmail.com wrote:   > 3. Everyone reads the label only after the product has been consumed.   Another way to find out what's in a product it to read its Materials Data Sheet (MSDS) - any substance that's transported before being sold or used will have one because its often a condition of transport contracts that it has one. Here's a good starting point:https://www.msdsonline.com/   https://hazard.com/msds/index.php https://www.msdsonline.com/   ... but unfortunately the first of these is somewhat flaky - quite possibly related to the US Governmental shutdown, since its been good in the past.     -- Martin | martin at Gregorie | gregorie dot org

Fox's Mercantile <jdangus@att.net>: Jan 14 03:35PM -0600 > hobby. So, I do not have to warrant anything. Were I to, > you bet that anything I used on my bench would be a > supportable name-brand product designed for the use-at-hand.   I go through this same argument about using SnapOn tools vs Craftsman. "But Craftsman is lifetime warranty too." Perhaps, but I've never had to stop in the middle of a job and hunt down a SnapOn tool dealer to replace something that shouldn't have broken in the first place.   I make a living with my tools and materials. NOT standing in line replacing things.       -- "I am a river to my people." Jeff-1.0 WA6FWi http:foxsmercantile.com

Jeff Liebermann <jeffl@cruzio.com>: Jan 14 01:50PM -0800 >I've learnt something today. I wasn't aware that paying a tenth >the price for a better & entirely customisable product was a >form of wizardry. Nor that it wasted time or money.   I have a book "Fortunes in Formula" (1939). 853 pages and 10,000 formulas. It has just about everything one might want from cleaning formulas to medical concoctions. It has served me well over the years. Unfortunately, it uses the "common" names for chemicals. For example: aqua fortis = nitric acid horn silver = sliver chloride oil of vitriol = sulphuric acid sugar of lead = lead acetate verdigris = copper acetate The medical preparation section uses the Latin names for everything. Decoding the formulas does require an extra step in translation, but is survivable.   A recent example of home chemistry is my annual problem with moss growing on my wood outside stairs. The moss turns to slime when the light and temperature is right, making my stairs rather hazardous. I've been using the overpriced commercial preparation, which works, but not very well. This year, I decided to try something from the book, which turned out to be a vinegar, washing soda, salt, and water preparation. It didn't work well in my sprayer, but it worked much better than anything else I've dried with a scrub brush and garden hose. My guess is I saved about $40 by essentially replacing the commercial preparation with hardware store vinegar.   >Retail concoctions often work, but often not adequately IME.   Yep. I've had the same experience.   >Really it never ceases to amaze me what people pay for mostly water.   When I was young, stupid, and impoverished, I did some work for a neighbor helping him prepare a laundry product in his garage. The work was boring, but the owner had me fascinated with his stories about his WWII TNT factory. The laundry ingredients were initially fairly common and easily mixed. Yes, it was mostly water. However, there were obscure additives that were quite necessary, usually to solve uncommon or odd problems. The customers were getting mostly water, but the common ingredients and obscure additives were what they really were buying. The product eventually became a commercial success and was sold to a large conglomerate.   -- 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

Fox's Mercantile <jdangus@att.net>: Jan 14 05:05PM -0600 On 1/14/19 3:50 PM, Jeff Liebermann wrote: > problems. The customers were getting mostly water, but the > common ingredients and obscure additives were what they really > were buying.   Exactly. I am more than happy to pay for stuff that works instead of mucking about trying to "make my own."   Two things of note, brake fluid really does stop weeds in your driveway cracks, and lamp oil (paraffin oil) is considerably cheaper than Saddle Soap.   I did learn how to make Prussic Acid, but that's pretty iffy. I'd rather my enemies drop dead from natural causes or through their own misfortune.       -- "I am a river to my people." Jeff-1.0 WA6FWi http:foxsmercantile.com

tabbypurr@gmail.com: Jan 14 04:55PM -0800 On Monday, 14 January 2019 23:05:12 UTC, Fox's Mercantile wrote: > > were buying.   > Exactly. I am more than happy to pay for stuff that works instead > of mucking about trying to "make my own."   I have more success with my own formulations than retail preparations, mostly at far less cost. I don't see any upside to going retail. I'll use them when they're good, eg washing powder, but many things it's easy to do better. Retail descalers are especially time & money wasting.     NT

ggherold@gmail.com: Jan 14 10:35AM -0800 > I've not started on the '36 yet, so am looking for any preliminary comments. The motor runs but is stiff, so will open that up. It has the original 1930s bag which I absolutely do not want to see damaged - but it's filthy and I assume well clogged. IME cloth bags on old hoovers always need thorough washing, question is how I can do that without degrading the applied lettering or bobbling the cloth? Handwashing in lukewarm water has some tendency to cause such damage.   > There's also a much later junior with a seized motor. Other than that it works great ;)   > NT   Do you repair these for fun or profit? Searching for Hoover 375 I found some site called vacuumland.org. I assume you know it already.   George H.

tabbypurr@gmail.com: Jan 14 11:33AM -0800 > Do you repair these for fun or profit? Searching for Hoover 375 I found > some site called vacuumland.org. I assume you know it already.   > George H.   I saw the vintage section on there, limited info there though. Seen a few youtube vids too, nothing so far on repairing the motors.   I like a lot of old stuff, not just vacs. When people say 'you can't live in a museum' I say 'why?' There seems to be some sort of belief that technology has changed out of all recognition, that living with old tech is not practical. That ain't so at all in many areas. Half a century old is a bit modern for me.     NT

N_Cook <diverse@tcp.co.uk>: Jan 14 08:06PM > I've not started on the '36 yet, so am looking for any preliminary comments.. The motor runs but is stiff, so will open that up. It has the original 1930s bag which I absolutely do not want to see damaged - but it's filthy and I assume well clogged. IME cloth bags on old hoovers always need thorough washing, question is how I can do that without degrading the applied lettering or bobbling the cloth? Handwashing in lukewarm water has some tendency to cause such damage.   > There's also a much later junior with a seized motor. Other than that it works great ;)   > NT   On the safety front, no perished rubber sleeving/insulation ?

tabbypurr@gmail.com: Jan 14 04:44PM -0800 On Monday, 14 January 2019 20:06:33 UTC, N_Cook wrote:   > > There's also a much later junior with a seized motor. Other than that it works great ;)   > > NT   > On the safety front, no perished rubber sleeving/insulation ?   Mechanically they're in worse shape than I expected, but electrically they're fine. 2 have clearly had their leads replaced, rubber doesn't last forever. The 119s even meet the criteria for double insulated appliances - don't know about the 30s one yet. It's original rubber lead is still serviceable.   What's it like to live with a 1940s 225watt vacuum cleaner? Well, I won't be making any of these my daily machine. Compared to modern vacs the 119s are heavier & metal based, both of which increase the rolling friction significantly. As for suction, the 225W motor with its inefficient dirty airstream fan does the job ok. I think the beater bars are the key to that, a clever innovation. Emptying the bag can be messy if windy. The original instructions said first put down newspaper. I'll stick to emptying them outdoors direct into a bin. I may try using paper bags with them to avoid the bags eventuallly clogging - not that I plan to use them much. They do the job but I'd rather use the Dyson (currently getting repaired).   I've not tried using the handheld hose/wand yet, but everything I've heard & figured out tells me that on the hose they're terrible. 225W with no form of agitation - meh, the 1930s dustette beats that.   Old tech is an eyeopener sometimes. Besides often being ingenious, some of it can do things modern tech struggles to.     NT

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