That would be asking too much.
As for me, I went to school for the training I needed for professional servicing.
But I digress.
Looking at a picture of the Weston 981, I can see why it's so confusing:
https://vintagetubeelectronics.com/wp-content/uploads/2018/04/Weston-981-Type-3.jpg
The pictured one is (magically) set up for a 6L6, but the selector settings are very obscure. For example, there's no connection to pin 2, IF the selector settings worked like, for example, a TV-2, but apparently they don't.
Maybe with an AC voltmeter you could determine first, whether the filament pinout is correct (measure 6-7 VAC across pins 2 and 7), and second (with power off and unplugged a while) whether there's continuity between pins 1 or 6 with any other pins.
Or maybe you'll get lucky and somebody familiar with that tester will chime in.
FWIW, most testers provide filament voltage at all times, but only supply other voltages during TEST. Assuming this is a known good, proven, tester, are you hearing more arcing than just filaments? Tough to say maybe.
All good fortune,
Chris
https://vintagetubeelectronics.com/wp-content/uploads/2018/04/Weston-981-Type-3.jpg
The pictured one is (magically) set up for a 6L6, but the selector settings are very obscure. For example, there's no connection to pin 2, IF the selector settings worked like, for example, a TV-2, but apparently they don't.
Maybe with an AC voltmeter you could determine first, whether the filament pinout is correct (measure 6-7 VAC across pins 2 and 7), and second (with power off and unplugged a while) whether there's continuity between pins 1 or 6 with any other pins.
Or maybe you'll get lucky and somebody familiar with that tester will chime in.
FWIW, most testers provide filament voltage at all times, but only supply other voltages during TEST. Assuming this is a known good, proven, tester, are you hearing more arcing than just filaments? Tough to say maybe.
All good fortune,
Chris
Thats a good Idea, I can check this when I get back home.
Im pretty sure it only applies the supply voltages until the selector switch is set to the emissions test, but I need to check this.
I wish there was more tube data around for this tester, its a very nice tester to use, especially the ease of testing double triodes.
Never have seen one in person, but looks beautiful in pix. Always been a big fan of anything Weston - they're a class act from the old school.
YOS,
Chris
YOS,
Chris
6L6GC or 7027 Heater Resistance Hot vs Cold
I ran this several years ago as well as several other devices, diodes, LEDs. Incandescent Lamps & so on. For the 6L6 & several other heater types cold to operating temp the resistance change is about 10:1.🙂
I ran this several years ago as well as several other devices, diodes, LEDs. Incandescent Lamps & so on. For the 6L6 & several other heater types cold to operating temp the resistance change is about 10:1.🙂
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just got a friend to test it on his TV-7u tester and it tests as new!
Anyway, its definitely a 7027, but am trying to see if there is a way to work out the switch settings on my Weston 981. Ive read that the heathkit tt1 tester is the same circuit and uses the same switch settings, although looking at the tube data for that tester, it appears to list another 3 selector switches compared to the 981, but the tester still has the same amount on the panel, so am unsure.
If anyone is familiar with the heathkit tester, that would be great.
Anyway, its definitely a 7027, but am trying to see if there is a way to work out the switch settings on my Weston 981. Ive read that the heathkit tt1 tester is the same circuit and uses the same switch settings, although looking at the tube data for that tester, it appears to list another 3 selector switches compared to the 981, but the tester still has the same amount on the panel, so am unsure.
If anyone is familiar with the heathkit tester, that would be great.
You can test it on your tester as a 6L6, being mindful of the difference at pin1. If the tester wants to tie shield to ground, ignore it. 7027 uses that pin as a duplicate G2. All other settings are the same. Translating from the roll chart's 9 digit code to socket pin numbers could be done by comparing several different valves' chart codes.
Theoretically. I tried comparing the highlighted 6L6 and 12SN7 in the picture and couldn't get anywhere. Might need more examples. Or, build a "socket-saver" that has no connection through pin1 and test away.
YOS,
Chris
Theoretically. I tried comparing the highlighted 6L6 and 12SN7 in the picture and couldn't get anywhere. Might need more examples. Or, build a "socket-saver" that has no connection through pin1 and test away.
YOS,
Chris
Yes it should be simple enough, if you or anyone else here knows of any tubes that has the same pinouts at the 7027, it will be piece of cake to figure it out, as there will be likely something that is listed on my scroll chart.
My 1973 GE manual shows no other valves using the 8HY pinout, and it's pretty comprehensive.
All you really want is to confirm that the tester isn't connecting pin1 to anything; then you can use the 6L6 settings. Continuity tests within the socket, power off and unplugged of course, will tell you that.
Then, set up for a 6L6 and test the empty socket for reasonable voltages, especially pin1. Finally, test away. All these precautions are for the safety of the tester, more than the valve itself.
All good fortune,
Chris
All you really want is to confirm that the tester isn't connecting pin1 to anything; then you can use the 6L6 settings. Continuity tests within the socket, power off and unplugged of course, will tell you that.
Then, set up for a 6L6 and test the empty socket for reasonable voltages, especially pin1. Finally, test away. All these precautions are for the safety of the tester, more than the valve itself.
All good fortune,
Chris
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I found the settings for the Heathkit TT1 here and have done some tests:
https://www.pestingers.net/pdfs/heathkit-test/t1a-supplemental-78.pdf
The configuration on the selector switches are quite different than that of a 6L6
Whats more, the bias settings on the heathkit data was essentially maxed out at 50H but slightly lower meter sensitivity at 35
The scroll chart on the weston for 6L6 is 35H and 40 for sensivitity.
What I find odd is the heathkit settings for the 7027 dont have a multiplier and the tube reads near the top of the scale, whereas when I tested the tube using 6L6 bias and meter settings as listed on the scroll chart (and turns out its the same as the link above) i got a reading typical of a NOS 6L6.
Im not sure why its got different sensitivity settings for the 7027, but the scale goes only to 3000 michroms which is a reading that is still less than a brand new tube so a multiplier on the scale is still needed.
Any ideas?
EIther way, im confident with the readings Im getting if i test with the 6L6 meter and bias data.