9-pin socket question

[islandjimmy]

Hi All,

I am building my third 5E3 amp kit. The 9-pin sockets on my current build have a center post. I have not seen one of these before and I am not sure what the center post is for? It seems like it will get in the way when I wire across from pins 8 to 3. Anyone know what I should do with this extra center post?


Thank you!

 

[elpico]

It's just an extra terminal you can use to connect components to. It's completely optional, you don't have to use it if you don't want it.

 

[tubegeek]

Ideally it is grounded but it doesn't matter much at audio frequencies - it would add just a bit of shielding between the two triodes in a dual triode tube. More important for radio frequency equipment.

At audio frequencies it's just an extra terminal to do whatever you'd like. Or nip it off if it's in the way.

 

[islandjimmy]

Ideally it is grounded but it doesn't matter much at audio frequencies - it would add just a bit of shielding between the two triodes in a dual triode tube. More important for radio frequency equipment.

At audio frequencies it's just an extra terminal to do whatever you'd like. Or nip it off if it's in the way.

Ah, I see. Thank you for the explanation. I will probably nip it off.

 

[tubegeek]

I'm assuming you're not looking to add a Geiger counter or shortwave transmitter feature to your 5E3 this time? Although - it WOULD be pretty cool.

 

[tubegeek]

There are tube sockets with like a Christmas tree of terminal points growing from that center spigot, so you can make circuits right on the socket, super-compact.

The RF guys have all the really tricky stuff. This one is octal but you get the idea.

 

[tubegeek]

While googling I found this, from an IBM mainframe. Now THAT's a layout.

 

[David Barnett]

While googling I found this, from an IBM mainframe. Now THAT's a layout. View attachment 777353

So IBM used Mustard caps? Another good source for harvesting parts.