Broken valve socket

[DonaldStott]

After replacing the ECC83 valve on a PYE stereogram (thanks to Forum member greg_simons) to resolve a Balance issue the amp module stopped working!

Traced the problem to a broken valve pin socket which feeds the valve heater which is why the ECC83 wasn’t heating up and therefore not conducting.



I temporarily bodged a piece of copper wire into the Pin 9 valve socket and everything seemed to be working again! When I have time I’ll recheck all valve pin voltages and confirm again that the previous Balance issue is resolved by fitting the replacement ECC83.

Now my question is can the broken valve pin socket be easily replaced or do I need to purchase a new B9A valve base? Of course replacing the valve base is a bit of a challenge as it is riveted so will need drilled out. Not to mention of course the numerous connections to the nine pins that will all need to be dealt with!

[vinrads]

Hi Donald, can you tell us what other valves are in the set, my thinking is to pinch a not used pin from another base.

Mick.

[DonaldStott]

Originally Posted by vinrads

Hi Donald, can you tell us what other valves are in the set, my thinking is to pinch a not used pin from another base.

Mick.

Great bit of lateral thinking Mick - I’ll take a closer look as I have 4 x ECL82 and 1 x EZ81 so plenty to choose from?

How easy is it to change a pin in a B9A valve base?

[DonaldStott]

Ok - tried to extract one of the spare pins from the EZ81 valve but stopped when the porcelain started showing some signs of ‘distress’! Maybe there’s a technique to this?

Don’t want to end up having to replace two B9A valve bases!

[vinrads]

They are usually held in by a little pip on the underside you will file this off. I will have a look to see if I have a base so I can be sure. PS just had a look, the one I have has the pin bent over at right angles I straightened it and it came out no problem. Can you send a pic of the bottom of the base.

Mick.

[greg_simons]

Originally Posted by DonaldStott

After replacing the ECC83 valve on a PYE stereogram (thanks to Forum member greg_simons) to resolve a Balance issue the amp module stopped working!

Traced the problem to a broken valve pin socket which feeds the valve heater which is why the ECC83 wasn’t heating up and therefore not conducting.

Attachment 278498

I temporarily bodged a piece of copper wire into the Pin 9 valve socket and everything seemed to be working again! When I have time I’ll recheck all valve pin voltages and confirm again that the previous Balance issue is resolved by fitting the replacement ECC83.

Now my question is can the broken valve pin socket be easily replaced or do I need to purchase a new B9A valve base? Of course replacing the valve base is a bit of a challenge as it is riveted so will need drilled out. Not to mention of course the numerous connections to the nine pins that will all need to be dealt with!

Hi there,
Back in the day it was perfectly possible to replace just an individual contact pin from another valve base, just remove the appropriate wiring and thoroughly clean the pin and remove by pushing it up from the bottom, glad it it was a simple fix!.
Best regards
Greg.

[Boulevardier]

" just remove the appropriate wiring and thoroughly clean the pin and remove by pushing it up from the bottom,"


But presumably there must be some sort of "ratchety" catch on the pin-sockets to prevent them all coming out of the ceramic base when you remove the valve. So just a question of working out where that is on each pin and releasing it while pushing the pin upwards and out - probably using something like a fine jewellers' screwdriver blade.
Mike

[DonaldStott]

Thanks for all the helpful advice.

I’ll try again tomorrow and post some pictures - maybe I’m just being a bit ham-fisted although access is difficult next to the mains transformer!

What amused me is that there are six valves making 54 pins in total and only 2 are unused!

[vidjoman]

The usual way was just giving the tag end a slight twist so it didn’t slip back through the slot.

[G6Tanuki]

Pragmatically, if one pin has failed in the socket I would be thinking that this is a hint to replace the socket...

Yes the horrible Mcmurdo type sockets were amenable to swapping tuning-fork type contacts, but the socket under discussion seems to be a ceramic type.

New sockets are available, fitting one would be my preference if only to avoid coming back to the thing with another failed contact in the coming decades

[DonaldStott]

I’m going to order up a couple of replacement B9A 9 pin valve bases just in case the valve pin socket transplant doesn’t go well!

Any recommendations - these seem ok:-

https://www.watfordvalves.com/produc...BoCbksQAvD_BwE

[Boulevardier]

Originally Posted by DonaldStott

I’m going to order up a couple of replacement B9A 9 pin valve bases just in case the valve pin socket transplant doesn’t go well!

Any recommendations - these seem ok:-

https://www.watfordvalves.com/produc...BoCbksQAvD_BwE

Or, Cricklewood also sell the ceramic version.


Mike

[vinrads]

Hi Donald don't buy those. If you need a socket let me know. Getting back to the faulty socket, please let's have a picture of the bottom of the socket it's a simple job. I don't know why it has caused all this talk.

Mick.

[murphyv310]

Replaced umpteen pins over the years.
There is usually a little tab on the connection right at the socket to stop it getting pulled up when removing the valve. Just compress the tab with pliers and push it out. Heater connections always seem to fail first no doubt due to conducted heat and a few more milliamps.

[DonaldStott]

Pin socket transplant Phase 1 complete: -



Had to remove the very heavy stereo amp module from the chassis (again!) in order to get proper access to the valve base.

Now on to Phase 2 ...

[murphyv310]

The retaining tab can be clearly seen halfway down the pin.