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Components and Circuits For discussions about component types, alternatives and availability, circuit configurations and modifications etc. Discussions here should be of a general nature and not about specific sets. |
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20th Jan 2023, 3:03 pm | #21 |
Octode
Join Date: Jul 2008
Location: Gloucestershire, UK.
Posts: 1,043
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Re: Help ID this unmarked valve
Hello,
There's a circuit and other info for a PL508 amplifier in this old thread. https://www.vintage-radio.net/forum/...d.php?t=170827 Yours, Richard |
20th Jan 2023, 3:15 pm | #22 | |
Hexode
Join Date: Mar 2019
Location: Edinburgh, Scotland, UK.
Posts: 341
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Re: Help ID this unmarked valve
Quote:
Here's the schematic downloaded from the original article. |
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20th Jan 2023, 3:46 pm | #23 |
Octode
Join Date: Nov 2005
Location: Surrey, UK.
Posts: 1,869
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Re: Help ID this unmarked valve
It looks to me as though the cathodes of the ECC82 driver should be earthed. The bias chain resistor values are unfriendly, and there's no protection for wiper lifting on the adjuster - poor design...
Leon. |
21st Jan 2023, 8:36 pm | #24 | ||
Dekatron
Join Date: Dec 2007
Location: Haarlem, Netherlands
Posts: 4,185
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Re: Help ID this unmarked valve
Quote:
Heerlen did manufacture colour TV valves well into the 1970's, and since this type of valve (and a 4 character date code) is unlikely to be from 1960, it's almost certainly made in 1970. |
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26th Jan 2023, 6:13 pm | #25 | |||
Hexode
Join Date: Mar 2019
Location: Edinburgh, Scotland, UK.
Posts: 341
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Re: Help ID this unmarked valve
Quote:
I checked my original one and it has a very faded 6 as above the 4 digit code. They are identical otherwise. Photo attached, the 'ne' one is on the right, you can read the codes at the bottom right. Doug |
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29th Jan 2023, 1:36 am | #26 |
Dekatron
Join Date: Dec 2007
Location: Haarlem, Netherlands
Posts: 4,185
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Re: Help ID this unmarked valve
That would be t16. I think that's a plausible code for 1970/1971. I know of a t1A from 1973.
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