Hello Peter,

I expected to find the tube at http://www.tubedata.org/ where Frank
Philipse has been collecting tube data sheets for 15 years but it wasn't
... It must be a very exotic tube!

73
Johan SM6LKM


Petr Maly skrev 2014-07-07 09:20:
> Hello all
>  
> I apology for the off-topic. However I know that this group is attended
> by very experienced gents, mainly from the UK.
> I found these two tubes in the junk, see the attachment. I spent quite a
> while to search the whole Internet for some specs, in vain.
> They are very similar to QB3/300, or TESLA’s RE125, same size, same
> socket. The only visible difference is the shape and material of the anode.
> I think the number 55 in the designation could possibly be the anode
> dissipation.
> The labels are:
> STC 4B/55
> ITT 4B/55/B
> By some lucky chance does anybody have any information about them?
>  
> Thanks, 73, Petr, OK1FIG
>  
>  
>