Valve bases, B9A etc.
 

Two different sizes of above can be obtained from Modulus Electronics, with thanks to Paul JD. I couldn’t find the size I required, 18mm, on the popular.
Cheers
John

Re: Valve bases, B9A etc.
 

Sorry i should have said ModulusAmplification.com
Cheers
John

Re: Valve bases, B9A etc.
 

I also understand that Langrex stock different size valve bases.
Cheers
John

Re: Valve bases, B9A etc.
 

Some B9 bases are definitely made for different sizes chassis holes, that includes both top and under chassis mounting types.And ceramic vs phenolic types. I have been caught out a few times myself. Many sellers do not specify the exact sizes then you can get a good or a bad surprise when they arrive. Some of the reproduction ceramic sockets from the Far East fit the larger size hole too.

Re: Valve bases, B9A etc.
 

Yes I got caught out ( I’m not a cricket fan!) recently, I had a faulty base in the Pye Bb I’m restoring, I ordered a ceramic base, assuming it would fit hole but alas it was too big. Thankfully a forum member came to the rescue.
Cheers
John

Re: Valve bases, B9A etc.
 

Some B7g, B9a and B9d valve sockets (in particular, also several other types) have stamped sheet metal skirt and socket insert that are made to be assembled either way up in order to make them under- or over-chassis mounting and can be reversed by carefully opening up the crimped-over lugs, inverting the insert and re-crimping.