Nascom 2 keyboard connector

Tony Duell ard at
Tue Jun 14 18:26:20 CDT 2005

> At 00:29 04/06/2005, you wrote:
> >They're a bit like the good old Q-max cutters (now that is showing my age
> >[1]).
> >
> >[1] The first 3 I ever bought, over 25 years ago, were 5/8", 3/4" and
> >1+1/8". Why?
> >
> >-tony
> You were building a Mullard 5/10 valve (tube) amp!

Close, but no cigar :-)

The 5-10 (5 valves 10 watts) used an EF86, ECC83, 2 off EL84 and an EZ81. 
All are on B9A bases, so I'd only have needed the 3/4" punch. I can't 
remember the hole size for the Bulgin plugs used for the mains and 
speaker connections, but I think it was smaller than 1+1/8".

Now, had you said the 5-20 (line up : EF86, ECC83, 2 off EL34, GZ32), 
then I would have needed the 3/4" and 1+1/8". And had I also been 
building the companion FM tuner, I would have needed the 5/8" (for the 
EB91 detector double diode, I think the B8A 'rimlock' sockets for the 
EF41s would go in a 3/4" hole).

Yes, I do have the appropriate Mullard books. And the Williamson 
reprints. And the GEC book on audio amplifiers (which starts with the 
Williamson and goes on to a monster with a rated 1.1kW audio output power).


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