ZX81 denigrated! (was Re: Approaches to projects)

[Tony Duell]

> > Yes. You could also feed in 7.5V through one of the sockets -- it was
> a
> > '240 degree' DIN socket used for external power, remote control, and
> > monitoring earphone. One thing I must do is make a little adapter
> with a
> > power connector and a remote control socket wired to a suitable plug.
> 
> That's the one.  I use that for power and remote from the Beeb.

Philips used that connector on several of their cassette recorders -- and 
the DC input may well not be 7.5V in all cases...

When I make the adapter I'll add a 3 position switch to it (the adapter),
postiions being 'Always on'. 'Always off', 'Controlled by the remote
cable). One of my Tandy cassette recorders, designed for home computer 
use, has such a switch, and it's useful.

Now, this nect bit is very off-topic, but.... I've got a older Philips 
Reel-to_-Reel recoerder with a strange socket for the record player 
input. According to my shelf of schematics for such things, several other 
Philips-made tape recorders (sold also under the Cossor and Stella names 
had this connecotr, either on its own, or with a normal DIN socket wired 
in parallel. The connector has 5 flat pins in a line, arranged something 
like : 

 | -- -- | --

There is no overall screening can. The pins are named p, q, r, s, t, 
every alternate pin is chassis ground, the other 2 being the 2 audio 
channels. According to the service manual for my machine, it's called an 
'IEC socket' and I have the Philips part number for the socket and the 
mating plug.

What I can't find, though, is any reference to the plug ever having been 
used. I can't find any mention of a record player fitted with said plug 
on the pickup cable. Has anyone ever come across it.

> 
> > Ah, I was wondering if it would work with a Beeb... Mine alsoe needs
> new
> > drive belts, but otherwise is still operational. I have the schematic
> > from the appropriate year of 'Radio and Television Servicing',
> although
> > sometimes oen was folded up inside the machine anyway.
> 
> I had to replace the drive belt in mine a few years back.  I got a belt
> from CPC for a few pence.

There are 2 belts in mine. The large one (which has completely died) 
which goes between the motot, capstan flywheel and reel drive pulley, and 
a little one in the reel drive mechanism. I was going to change both. I 
don't suppose you've got the CPC number for the belt you used, the CPC 
catalogue is almost impossible to obtain...

-tony