American all metal Rectifier ID - UK Vintage Radio Repair and Restoration Discussion Forum

Megatron · 20th Feb 2021, 6:14 pm

I have a few all metal unidentified valves. Two in particular are metal 6L6 size, but have 5 pins. I think theyre most likely rectifiers, and are certainly the same size as a 5T4 metal Rectifier. Does anyone know what rectifiers were made with metal envelopes that fit the description?
I think theyre too big for a 5Z4. Dont know if direct or indirect heated yet.
Candidates are 5U4 5T4 are there any others.

?
Also how do you edit a thread heading!!

ms660 · 20th Feb 2021, 6:50 pm

5W4 has 5 pins.

Lawrence.

Megatron · 20th Feb 2021, 7:13 pm

5W4 looks quite short,? at least shorter than a 6l6.

ms660 · 20th Feb 2021, 7:43 pm

Quote:

Originally Posted by Megatron

5W4 looks quite short,? at least shorter than a 6l6.

Yes I know but it's a rectifier with 5 pins, maybe one of his others, I've come across metal valves where their height doesn't always tally up with what's printed on them, I think they might have been re-branded ones.

Lawrence.

Megatron · 21st Feb 2021, 1:21 pm

Definetley direct heated rectifier, tests same as a 5u4
I think i will just lob it in the rectifier valve tub marked as 5U4??

usradcoll1 · 21st Feb 2021, 6:24 pm

Quote:

Originally Posted by ms660

Quote:

Originally Posted by Megatron

5W4 looks quite short,? at least shorter than a 6l6.

Yes I know but it's a rectifier with 5 pins, maybe one of his others, I've come across metal valves where their height doesn't always tally up with what's printed on them, I think they might have been re-branded ones.

Lawrence.

If the valve is the physical size of a 6L6, but only 5 pins, it is definitely a 5T4! It's part of the early range of metal valves that RCA introduced in mid-1935.
I don't think it was in production very long. It doesn't quite measure up to a 5U4 and only has a 2amp, 5volt heater, where the 5U4 has a 3amp heater.
It was soon replaced by the 5Z4. The evolution of valves in the US, as well as other countries is interesting, to be sure!
Dave, USradcoll1

Radio Wrangler · 21st Feb 2021, 7:57 pm

5R4 is bigger than 5Z4

David

Megatron · 22nd Feb 2021, 9:07 pm

Quote:

Originally Posted by usradcoll1

Quote:

Originally Posted by ms660

Quote:

Originally Posted by Megatron

5W4 looks quite short,? at least shorter than a 6l6.

Yes I know but it's a rectifier with 5 pins, maybe one of his others, I've come across metal valves where their height doesn't always tally up with what's printed on them, I think they might have been re-branded ones.

Lawrence.

If the valve is the physical size of a 6L6, but only 5 pins, it is definitely a 5T4! It's part of the early range of metal valves that RCA introduced in mid-1935.
I don't think it was in production very long. It doesn't quite measure up to a 5U4 and only has a 2amp, 5volt heater, where the 5U4 has a 3amp heater.
It was soon replaced by the 5Z4. The evolution of valves in the US, as well as other countries is interesting, to be sure!
Dave, USradcoll1

yes agreed its a 5T4

that jogged my memory, i had a few of them with very feint markings, they must have rubbed off altogether.

20th Feb 2021, 6:14 pm	#1
Megatron Pentode Join Date: Mar 2019 Location: Monmouth, Monmouthshire, Wales, UK. Posts: 166	American all metal Rectifier ID I have a few all metal unidentified valves. Two in particular are metal 6L6 size, but have 5 pins. I think theyre most likely rectifiers, and are certainly the same size as a 5T4 metal Rectifier. Does anyone know what rectifiers were made with metal envelopes that fit the description? I think theyre too big for a 5Z4. Dont know if direct or indirect heated yet. Candidates are 5U4 5T4 are there any others.? Also how do you edit a thread heading!! Last edited by Cobaltblue; 20th Feb 2021 at 6:26 pm. Reason: title: Rectifier

20th Feb 2021, 6:50 pm	#2
ms660 Dekatron Join Date: Apr 2011 Location: Cornwall, UK. Posts: 13,454	Re: American all metal Rectifier ID 5W4 has 5 pins. Lawrence.

20th Feb 2021, 7:13 pm	#3
Megatron Pentode Join Date: Mar 2019 Location: Monmouth, Monmouthshire, Wales, UK. Posts: 166	Re: American all metal Rectifier ID 5W4 looks quite short,? at least shorter than a 6l6.

21st Feb 2021, 1:21 pm	#5
Megatron Pentode Join Date: Mar 2019 Location: Monmouth, Monmouthshire, Wales, UK. Posts: 166	Re: American all metal Rectifier ID Definetley direct heated rectifier, tests same as a 5u4 I think i will just lob it in the rectifier valve tub marked as 5U4??

21st Feb 2021, 7:57 pm	#7
Radio Wrangler Moderator Join Date: Mar 2012 Location: Fife, Scotland, UK. Posts: 22,899	Re: American all metal Rectifier ID 5R4 is bigger than 5Z4 David __________________ Can't afford the volcanic island yet, but the plans for my monorail and the goons' uniforms are done