Valve ID - UK Vintage Radio Repair and Restoration Discussion Forum

Diabolical Artificer · 16th May 2017, 1:14 pm

I recently got a box of valves from a forum member, two of these were in there. I thought they might be 2CXX or DETXX but have had no joy.

Any ideas?

Andy.

ms660 · 16th May 2017, 1:31 pm

?:

http://www.radiomuseum.org/tubes/tube_vt235.html

Lawrence.

G6Tanuki · 16th May 2017, 2:41 pm

I'd say that was it.

Essentially a top-cap-grid-and-anode version of the "717A" which was nicknamed "The Doorknob" for obvious reasons:

http://www.r-type.org/exhib/aab0012.htm

both of which date from the very-early-years of WWII.

The basic electrode-assembly used in both these valves subsequently found its way into the B7G-based 6AK5/EF95.

Diabolical Artificer · 16th May 2017, 3:04 pm

Thanks both, how did you find that Lawrence? Otherwise known as the HY615 or possibly NJ7P. Cute little valves AKA mickey mouse.

Andy.

ms660 · 16th May 2017, 3:13 pm

Index of valve bases...IO...then scroll 'till you find a midget with two ears:

http://www.r-type.org/inx/main-inx.htm

Once that's found you now have something to go on, eg: to find one of the ones that's probably in your picture (Hytron HY615 variant 2):

http://www.tubecollection.de/ura/hytron.htm

Lawrence.

16th May 2017, 1:14 pm	#1
Diabolical Artificer Dekatron Join Date: Jul 2009 Location: Sleaford, Lincs. UK. Posts: 7,670	Valve ID I recently got a box of valves from a forum member, two of these were in there. I thought they might be 2CXX or DETXX but have had no joy. Any ideas? Andy. Attached Thumbnails __________________ Curiosity hasn't killed this cat...so far.

16th May 2017, 1:31 pm	#2
ms660 Dekatron Join Date: Apr 2011 Location: Cornwall, UK. Posts: 13,454	Re: Valve ID ?: http://www.radiomuseum.org/tubes/tube_vt235.html Lawrence.

16th May 2017, 2:41 pm	#3
G6Tanuki Dekatron Join Date: Apr 2012 Location: Wiltshire, UK. Posts: 14,010	Re: Valve ID I'd say that was it. Essentially a top-cap-grid-and-anode version of the "717A" which was nicknamed "The Doorknob" for obvious reasons: http://www.r-type.org/exhib/aab0012.htm both of which date from the very-early-years of WWII. The basic electrode-assembly used in both these valves subsequently found its way into the B7G-based 6AK5/EF95.

16th May 2017, 3:04 pm	#4
Diabolical Artificer Dekatron Join Date: Jul 2009 Location: Sleaford, Lincs. UK. Posts: 7,670	Re: Valve ID Thanks both, how did you find that Lawrence? Otherwise known as the HY615 or possibly NJ7P. Cute little valves AKA mickey mouse. Andy. __________________ Curiosity hasn't killed this cat...so far.

16th May 2017, 3:13 pm	#5
ms660 Dekatron Join Date: Apr 2011 Location: Cornwall, UK. Posts: 13,454	Re: Valve ID Index of valve bases...IO...then scroll 'till you find a midget with two ears: http://www.r-type.org/inx/main-inx.htm Once that's found you now have something to go on, eg: to find one of the ones that's probably in your picture (Hytron HY615 variant 2): http://www.tubecollection.de/ura/hytron.htm Lawrence.