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Don Kuenz <g@crcomp.net>: Oct 11 04:13PM > weren't marked for temperature. It belonged to a bar, and they needed it right > away, so they paid a large bill to have it working the next day. I generally use > Panasonic and Rubicon for repairs and my projects, these days.   Near the turn of the century a Missouri man named Chris started badcaps.net Chris' "master list" enumerates the capacitors that he trusts:   https://www.badcaps.net/index.php?pageid=master_list   Chris also hosts a lively forum at https://www.badcaps.net/forum/ Although its more apropos to repair.   Thank you, 73,   -- Don Kuenz KB7RPU There was a young lady named Bright Whose speed was far faster than light; She set out one day In a relative way And returned on the previous night.

Ralph Mowery <rmowery28146@earthlink.net>: Oct 10 01:09PM -0400 In article <qnnkni$ga9$1@dont-email.me>, nojunk@knology.net says...   > Know one has mentioned it, but I have a question about the value 33uh. > Unless that is a very large resistor or a very small diameter wire... > I just question the value.   I ran some numbers a while back and nothing reasonable for 33 uH came out for an air wound coil that would fit on a 1/2 to 1 watt resistor. Maybe it was .33 uh.

etpm@whidbey.com: Oct 10 10:27AM -0700 On Thu, 10 Oct 2019 06:08:38 -0700 (PDT), "pfjw@aol.com"   >This is a hobby for me, so I do not take payment for anything I might do, and I reserve the right to be arbitrary. In general, I wish anything that leaves my hands to be as "safe and effective" as is reasonably possible, and certainly as reliable as possible. Just as I am not required or restricted to using single-weight, non-detergent oil in a vintage automobile, I am not require or restricted to use vintage parts in a vintage radio. Caps are cheap. Even to a hobbyist at $0.40 an hour, they are far cheaper than "Doing it over". Do them all, and be done with it.   >Peter Wieck >Melrose Park, PA The caps were pretty cheap, even the 450 volt electrolytics. So they are all getting replaced. Aside from probably being a good idea I really don't want a cap to go short down the road and ruin the power xmfr. The only caps I am not replacing are the little disc ceramic ones. I don't know yet what shape the tubes are in but since the scope does work now I think they are probably in good shape. The nearest tube tester to me that I know of is 80 miles away sso I can't test them except to see ho well the scope functions. I bet I can find a Ham that has a tube tester closer to me if I really want to test tubes. Might just be cheaper to find some new ones on eBay. Eric

tabbypurr@gmail.com: Oct 10 10:24AM -0700 > This is a hobby for me, so I do not take payment for anything I might do, and I reserve the right to be arbitrary. In general, I wish anything that leaves my hands to be as "safe and effective" as is reasonably possible, and certainly as reliable as possible. Just as I am not required or restricted to using single-weight, non-detergent oil in a vintage automobile, I am not require or restricted to use vintage parts in a vintage radio. Caps are cheap. Even to a hobbyist at $0.40 an hour, they are far cheaper than "Doing it over". Do them all, and be done with it.   > Peter Wieck > Melrose Park, PA   With paper caps I tend to agree. Electolytics are a mix, some are fine and will outlast whatever you would replace them with. Other types of old cap are usually reliable.     NT

Fox's Mercantile <jdangus@att.net>: Oct 10 12:42PM -0500 > really don't want a cap to go short down the road and ruin the power > xmfr. The only caps I am not replacing are the little disc ceramic > ones.   Like I said, collateral damage that is avoidable.   > does work now I think they are probably in good shape. The nearest > tube tester to me that I know of is 80 miles away sso I can't test > them except to see ho well the scope functions.   Once you've fixed all the cheap things, capacitors and way out of\ tolerance resistors, then you can worry about the tubes. Which I've found are usual still good.   > really want to test tubes. Might just be cheaper to find some new ones > on eBay. > Eric   Be careful, they'll try and teach you Morse code.       -- "I am a river to my people." Jeff-1.0 WA6FWi http:foxsmercantile.com

"pfjw@aol.com" <peterwieck33@gmail.com>: Oct 10 12:16PM -0700 No idea where you are, but if you are near Philadelphia, I can help with testing tubes. Between the big Hickok, which can match, or the little Simpson, I would have you covered.   Peter Wieck Melrose Park, PA

amdx <nojunk@knology.net>: Oct 10 03:26PM -0500 On 10/10/2019 12:09 PM, Ralph Mowery wrote:   > I ran some numbers a while back and nothing reasonable for 33 uH came > out for an air wound coil that would fit on a 1/2 to 1 watt resistor. > Maybe it was .33 uh.   Ya, I didn't run any numbers, I have wound quite a few air coils and 33uh seems like it would be kind off large, compared to a resistor*. So, it just doesn't seem right.   Mikek     *I know, how big is a resistor

etpm@whidbey.com: Oct 10 01:49PM -0700 On Thu, 10 Oct 2019 12:16:10 -0700 (PDT), "pfjw@aol.com"   >No idea where you are, but if you are near Philadelphia, I can help with testing tubes. Between the big Hickok, which can match, or the little Simpson, I would have you covered.   >Peter Wieck >Melrose Park, PA I'm north of Seattle. On an island. Eric

tabbypurr@gmail.com: Oct 11 04:46AM -0700 > really want to test tubes. Might just be cheaper to find some new ones > on eBay. > Eric   Easiest way to test tubes is to check the anode/cathode current in situ. The great majority of bad tubes aren't able to pass enough current, though other faults can exist.     NT

Fox's Mercantile <jdangus@att.net>: Oct 11 08:47AM -0500 > Easiest way to test tubes is to check the anode/cathode > current in situ. The great majority of bad tubes aren't > able to pass enough current, though other faults can exist.   More useless advice.   While this may be true with television sweep tubes used as RF final amplifiers, the proper way to test tubes "in situ" is to know what they're supposed to do and see if they do. Most faults can be zeroed in on by simply seeing if a function does what it's supposed to do.     -- "I am a river to my people." Jeff-1.0 WA6FWi http:foxsmercantile.com

"pfjw@aol.com" <peterwieck33@gmail.com>: Oct 11 07:38AM -0700 It is always the device itself that is the best tester of tubes. But for:   Thermal faults - mostly shorts, sometimes going open. A thermal short (or open) will not show up with a VOM when the tube is cold. Further, a rectifier short, for instance, could destroy a power transformer in very short order if not caught immediately, especially if the device is poorly fused (most are). This can be deadly to vintage equipment.   Cascade effects - this tube is a bit weak, and that tube is a bit weak, and yet a third tube is a bit weak. Now, the entire device is 'not quite right' but no singled tube would explain it. And, in the real world, it is this cascade issue that is most common. And, often, why otherwise salvageable devices find their way onto a shelf or into landfill. Sad.   Generally, a thermal fault would have been screened out of the device at some point, one hopes. But not always. And, generally, thermal faults while not immediate are usually quick enough that they would be caught in the initial testing. But not always.   Leads to a tiny rant on how to test a tube. Guys and Gals! Proper tube testing, even on an emissions-only tester, takes _AT LEAST_ ten (10) minutes per tube. First, the set-up and initial screen for shorts and gas. Then the (so-called) "Quality" test. Then, minutes 2 - 10, watch that meter and see what the tube does as it warms up and equalizes. And, at the end of it all, repeat the shorts/gas screening. Only now, do you have useful information.   NOTE 1: Some cheap testers are not capable of holding a heavy output tube for extended periods as the on-board power-supply is inadequate. Be cautious.   Note 2: A tube tester, even the finest Hickok or AVO tests a tube RELATIVE to an established norm or average. A tube may still function perfectly adequately even if all it does is barely lift the meter.   Note 3: Rectifier tubes are the exception to Note 2. They *must* be 'in the zone', or they will be either passing too much AC, or not enough DC, or both.   Note 4: Which leads to being at least aware that the tester in use needs calibration - if possible, or at least pre-testing with known-good tubes to see where the meter falls. Then, compare the others to that.   Tube testers are screening devices. They will indicate dangerous faults (shorts and gas) not possible by any other means other than possible damage to the "home" unit. And they will indicate absolute faults such as an open filament. And for those heavily into Audio, a vanishingly few will allow actual proper matching. After which, it is the "home unit".   A decent emissions-only tester is a handy device for anyone dabbling seriously in tube equipment. IT *may* (not necessarily will) save a bunch of time if used properly. And, a decent emissions tester will not break the bank, either. Leading, again, to:   Note 5: (Heresy Warning!) The step between a decent emissions-only tester and one that will actually convey enough additional information to be useful is considerable in complexity and in cost. A Heath TC3 for 99-44% of general hobby purposes is as good as any but the very top-of-the-line GM testers. That includes the TV-7 military tester and all its clones. The next step up are those capable of matching - or the modern computerized testers that will plot curves and so forth. So, from roughly $80 - $200 for a good, clean TC3 or-equal, to the $900 - $2,500-and-up for a properly calibrated Hickok 539 series, AVO or Card-Matic, don't bother with the in-between.   Peter Wieck Melrose Park, PA

Jeff Urban <jurb6006@gmail.com>: Oct 11 09:03AM -0700 >I will be replacing practucally every cap.   You should not until you get the trace to respond to a signal. UNLESS the scope is so old it does not have DC coupling it is not a capacitor.

Jeff Urban <jurb6006@gmail.com>: Oct 11 09:00AM -0700 Understand electronics much ? Or just what "someone wrote" ?   If you got a coil and cap like that, if the coil is not open it cannot make the trace disappear. It may not have quite the frequency response but it will still work.   There is nothing in a scope that old and limited that would suffer much from the opening up of a resistor that is bridged by a coil. Measure it, if it is not open move on and find the real problem. This ain't it.

Fox's Mercantile <jdangus@att.net>: Oct 11 09:39AM -0500 On 10/11/19 9:09 AM, KenW wrote:   >> Everytime i use my laptop at a public WIFI, I see PORTTHRU as i refresh >> my list of available networks. This is everywhere I am. What is it?   > Do a search and you will find out.   Tubeguy seems to be incapable of using google.     -- "I am a river to my people." Jeff-1.0 WA6FWi http:foxsmercantile.com

KenW <ken1943@invalid.net>: Oct 11 08:09AM -0600 >Everytime i use my laptop at a public WIFI, I see PORTTHRU as i refresh >my list of available networks. This is everywhere I am. What is it?   Do a search and you will find out.

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