UX7 Valve Base. - UK Vintage Radio Repair and Restoration Discussion Forum

Peter.G0DRT · 2nd Nov 2016, 12:16 pm

I needed to test a 1625 pentode on my Taylor 45c valve tester.The problem was I couldn't get the valve to go into the UX7 socket.On closer inspection I found that the socket spacings were narrower compared to the valve pin spacings.I tried the valve with a spare socket and the valve didn't fit. I'm a bit baffled because I thought there was only one type of UX7 base.

Regards.Peter.

Mr Moose · 2nd Nov 2016, 12:50 pm

Hello.

According to Wikipedia the UX7 is equivalent to a U7A (small) valve base.

According to the valve data the 1625 has a U7B (medium) valve base.

Yours, Richard.

Boater Sam · 2nd Nov 2016, 2:20 pm

Had this experience before with 807s too. There seems to be a confusion of UX7 bases. I just use croc clip leads now,, straight of my patch sockets on the tester.

Peter.G0DRT · 2nd Nov 2016, 3:14 pm

I can see why I was baffled. Thanks Richard for the info. I will have to do what Boater Sam does for testing purposes.

Cheers, Peter.

David G4EBT · 2nd Nov 2016, 5:31 pm

I've recently made some UX valve base adaptors to extend the range of my Taylor 45D Valve tester to enable the Octal test socket to be used, which I wrote up in another thread.

I got the bases from Hi-Fi Collective, very reasonably priced current manufacture in ceramic. They sell two styles of UX7, one of which id oval - the other is square:

http://www.hificollective.co.uk/cata...e-p-10247.html

http://www.hificollective.co.uk/cata...e-p-10248.html

The thicker pins are the heater pins - 1 & 7 on UX7.

The 807 uses a UX5 base - the thicker pins being 1 & 5.

The 813 uses a UX7 base and with the heater drawing 5 Amps at 10 Volts, no doubt the thicker pins are a good thing.

janpa3fyz · 2nd Nov 2016, 8:46 pm

Dear David,
The 807 valve has 5 pins, all of the same diameter.
Jan PA3FYZ

David G4EBT · 2nd Nov 2016, 9:13 pm

Thanks for reading my post Jan and for your response.

I don't have an 807 in front of me, and I'm not a valve 'afficionado' but I based my comments on this, which clearly shows larger diameter heater pins (1 & 5):

https://en.m.wikipedia.org/wiki/807_(vacuum_tube)

I'm confused now!

ms660 · 2nd Nov 2016, 9:27 pm

Tube base and cap info in the link below, includes JETEC No. A5-11 (807 valve) and JETEC No. A7-17 (813 valve)

http://www.tubebooks.org/tubedata/hb...eral/Bases.pdf

If that's any use.

Lawrence.

janpa3fyz · 3rd Nov 2016, 8:01 pm

I have the 807 in my collection and its five pins are all the same.
The RCA data-sheet (thanks to Lawrence) confirms this.
The wikipedia states the 807 base as follows: UY and not UX.
This is a correct name, but it shows a faulty pinout with 2 thick pins.
The AVO valve data manual also gives a wrong 807 base:UX5.
So there is some confusion about this matter.
best regards
Jan

Boater Sam · 4th Nov 2016, 8:56 am

I have many 807s and yes, they are UY5, all pins the same. My 1625s are the same too. There are listings for 807 bases on the Bay.

2nd Nov 2016, 12:16 pm	#1
Peter.G0DRT Pentode Join Date: Dec 2009 Location: Isle of Sheppey, Kent, UK. Posts: 148	UX7 Valve Base. I needed to test a 1625 pentode on my Taylor 45c valve tester.The problem was I couldn't get the valve to go into the UX7 socket.On closer inspection I found that the socket spacings were narrower compared to the valve pin spacings.I tried the valve with a spare socket and the valve didn't fit. I'm a bit baffled because I thought there was only one type of UX7 base. Regards.Peter.

2nd Nov 2016, 12:50 pm	#2
Mr Moose Octode Join Date: Jul 2008 Location: Gloucestershire, UK. Posts: 1,043	Re: UX7 Valve Base. Hello. According to Wikipedia the UX7 is equivalent to a U7A (small) valve base. According to the valve data the 1625 has a U7B (medium) valve base. Yours, Richard.

2nd Nov 2016, 2:20 pm	#3
Boater Sam Banned Join Date: Dec 2013 Location: Middlewich, Cheshire, UK. & Winter in the Philippines. Posts: 3,897	Re: UX7 Valve Base. Had this experience before with 807s too. There seems to be a confusion of UX7 bases. I just use croc clip leads now,, straight of my patch sockets on the tester.

2nd Nov 2016, 3:14 pm	#4
Peter.G0DRT Pentode Join Date: Dec 2009 Location: Isle of Sheppey, Kent, UK. Posts: 148	Re: UX7 Valve Base. I can see why I was baffled. Thanks Richard for the info. I will have to do what Boater Sam does for testing purposes. Cheers, Peter.

2nd Nov 2016, 5:31 pm	#5
David G4EBT Dekatron Join Date: Feb 2003 Location: Cottingham, East Yorkshire, UK. Posts: 5,761	Re: UX7 Valve Base. I've recently made some UX valve base adaptors to extend the range of my Taylor 45D Valve tester to enable the Octal test socket to be used, which I wrote up in another thread. I got the bases from Hi-Fi Collective, very reasonably priced current manufacture in ceramic. They sell two styles of UX7, one of which id oval - the other is square: http://www.hificollective.co.uk/cata...e-p-10247.html http://www.hificollective.co.uk/cata...e-p-10248.html The thicker pins are the heater pins - 1 & 7 on UX7. The 807 uses a UX5 base - the thicker pins being 1 & 5. The 813 uses a UX7 base and with the heater drawing 5 Amps at 10 Volts, no doubt the thicker pins are a good thing. Attached Thumbnails __________________ David. BVWS Member. G-QRP Club member 1339.

2nd Nov 2016, 8:46 pm	#6
janpa3fyz Triode Join Date: Sep 2010 Location: Utrecht, The Netherlands Posts: 21	Re: UX7 Valve Base. Dear David, The 807 valve has 5 pins, all of the same diameter. Jan PA3FYZ

2nd Nov 2016, 9:13 pm	#7
David G4EBT Dekatron Join Date: Feb 2003 Location: Cottingham, East Yorkshire, UK. Posts: 5,761	Re: UX7 Valve Base. Thanks for reading my post Jan and for your response. I don't have an 807 in front of me, and I'm not a valve 'afficionado' but I based my comments on this, which clearly shows larger diameter heater pins (1 & 5): https://en.m.wikipedia.org/wiki/807_(vacuum_tube) I'm confused now! __________________ David. BVWS Member. G-QRP Club member 1339.

2nd Nov 2016, 9:27 pm	#8
ms660 Dekatron Join Date: Apr 2011 Location: Cornwall, UK. Posts: 13,454	Re: UX7 Valve Base. Tube base and cap info in the link below, includes JETEC No. A5-11 (807 valve) and JETEC No. A7-17 (813 valve) http://www.tubebooks.org/tubedata/hb...eral/Bases.pdf If that's any use. Lawrence.

3rd Nov 2016, 8:01 pm	#9
janpa3fyz Triode Join Date: Sep 2010 Location: Utrecht, The Netherlands Posts: 21	Re: UX7 Valve Base. I have the 807 in my collection and its five pins are all the same. The RCA data-sheet (thanks to Lawrence) confirms this. The wikipedia states the 807 base as follows: UY and not UX. This is a correct name, but it shows a faulty pinout with 2 thick pins. The AVO valve data manual also gives a wrong 807 base:UX5. So there is some confusion about this matter. best regards Jan

4th Nov 2016, 8:56 am	#10
Boater Sam Banned Join Date: Dec 2013 Location: Middlewich, Cheshire, UK. & Winter in the Philippines. Posts: 3,897	Re: UX7 Valve Base. I have many 807s and yes, they are UY5, all pins the same. My 1625s are the same too. There are listings for 807 bases on the Bay.