Classic Hifi Care

Hello Guys this is a general question. Lets say I want to replace the socket for a 5U4gt how do I find out what socket it uses? Same for a 12AX7 tube. Also I notice you can get them in different colors and in ceramic and or Plastic? what is your go to standard pick ?
Do you have a book or a reference you can get the correct socket for the tube and does that also tell you the pin numbers ? Thanks in advance.

The 5U4 uses a standard octal tube socket. The 12AX7 would use a standard 9-pin miniature tube socket. The wafer sockets, commonly used as original equipment, are not my favorite type of tube socket. The best type as far as being rugged would be the ceramic type. Phenolic or bakelite sockets are good, too. Plastic tube sockets would work where they don't get a lot of heat. All four 5U4 tube sockets have been replaced on my CG before I got it. They used ceramic sockets. My recommendation as far as a type is concerned would be to use ceramic or bakelite tube sockets for replacement. You would use the same mounting system that original equipment used.

And try to find sockets made in the US, not China.

If it has gold-plated pins, it is Chinese.

Search within this forum for posts about stores selling vintage NOS electronic parts under the "Oh Jeez" title, and see about brands like Amphenol, Chinch, or Eby.

Wouldn't gold-plated contacts be an advantage? Do the Chinese versions have some other defects? OK, apart from being tiny objects that have to be shipped across an ocean, which seems really wasteful?

Chris Campbell

They don't old up well.

Silver contact surfaces have less resistances than gold. Optics is their hook.

Hydrolastic wrote: ↑Wed May 15, 2024 12:59 am Hello Guys this is a general question. Lets say I want to replace the socket for a 5U4gt how do I find out what socket it uses? Same for a 12AX7 tube.

Also I notice you can get them in different colors and in ceramic and or Plastic? what is your go to standard pick ?

Do you have a book or a reference you can get the correct socket for the tube and does that also tell you the pin numbers ? Thanks in advance.

If you an RCA or other tube manual,
it will reference the socket style and pin-out numbers.

If you look up a tube data sheet, it should give same info.

https://stewart-switch.com/vacuum-tube-base-diagrams

For hot output tubes, I'd use a ceramic tube socket base.

Surplus Sales Of Nebraska still carries a few different kinds of sockets...

https://www.surplussales.com/Tube-Socke ... kts-3.html

Thank you. I looked up the 5U4GB tube (google) and it says its a 5 pin octal tube so I started to look up the base called out. But it turns out its a 8 pin octal tube socket and the tube only uses 5 of the pins. So now I realize every tube has a datasheet. I have a long way to go.

There are only three types of tube sockets you are likely to encounter working on stereo equipment. The octal, the nine-pin miniature and the seven-pin miniature.

If any of you can't find those common sockets, let me know. I have more than I'll ever use...

DG

My eventual goal is to replace all 4 of the 5u4GB sockets in the concert grand I want to replace them with some retainers so it doesn't happen again.

My eventual goal is to replace all 4 of the 5u4GB sockets in the concert grand I want to replace them with some retainers so the tube stays in place as it is now the tubes on the left side don't always light up because the tubes (both) are loose.

I've been able to restress the pin sockets for miniature tubes that are constructed with phenolic sheets with a small set of hemostats and got reliable results. I gently squeezed the socket where it passes through the lower phenolic matrix. After having done so, I could see the sockets expand as the pins passed through the sockets. I've also had good luck cleaning the sockets with a interdental brush wetted in 91% isopropyl alcohol. The alcohol cleans tarnish from silver plated sockets.

Hydro,

Snap a photo of the old sockets from the front so I can match something up for you.

D

Hello Conelrad, Here is one photo of the actual problem socket and another photo of the 5U4GB socket from the AMP 182 BA from the continental and the bottom of the AMP 182 5U4GB socket. Thank you!

I'm pretty sure I have those in bulk NOS. I'll have to dig a bit and get back to you.

DG