|
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. |
|
Thread Tools |
4th Dec 2020, 12:52 pm | #1 |
Moderator
Join Date: Jan 2003
Location: Ipswich, Suffolk, IP4, UK.
Posts: 21,289
|
Double triode ID?
The pinout of this valve appears to be the same as that of ECC83's etc. but it's taller. Total heater resistance is about 8R cold. Only writing visible is "BRIMAR" and "MADE IN".
Anyone know what it might be? Thanks.
__________________
Graham. Forum Moderator Reach for your meter before you reach for your soldering iron. |
4th Dec 2020, 12:53 pm | #2 |
Moderator
Join Date: Dec 2010
Location: Exeter, Devon and Poole, Dorset UK.
Posts: 6,874
|
Re: Double triode ID?
__________________
Invisible airwaves crackle with life or at least they used to Mike T BVWS member. www.cossor.co.uk Last edited by Cobaltblue; 4th Dec 2020 at 12:54 pm. Reason: Added Link |
4th Dec 2020, 12:57 pm | #3 |
Moderator
Join Date: Jan 2003
Location: Ipswich, Suffolk, IP4, UK.
Posts: 21,289
|
Re: Double triode ID?
Seems likely, it came from a box of what were largely TV pulls. I'll give it a test.
__________________
Graham. Forum Moderator Reach for your meter before you reach for your soldering iron. |
7th Dec 2020, 9:19 pm | #4 |
Moderator
Join Date: Jan 2003
Location: Ipswich, Suffolk, IP4, UK.
Posts: 21,289
|
Re: Double triode ID?
Tests perfectly as a 12BH7 so a 12BH7 it is. Now labelled and boxed up in case I ever find a use for it.
Thanks Mike.
__________________
Graham. Forum Moderator Reach for your meter before you reach for your soldering iron. |
8th Dec 2020, 12:05 am | #5 |
Octode
Join Date: Nov 2005
Location: Surrey, UK.
Posts: 1,873
|
Re: Double triode ID?
The 12BH7 makes a very meaningful bias/erase oscillator valve for tape recorders. In a circuit originally designed for a 12AU7 (ECC82), with which it is pin compatible, it can provisde a useful increase in erase power at the expense of some HT and heater current.
Leon. |