Nytech CXA 252 amp

[Nigel Cook]

Also for the archives CXA252.
Very little on the www about this except someone else
who seems to have been here before but no resolution.
I wish to confirm this 1980 ? amp has not been tampered with
before i power-up and repair.
I have the schematics for the CTA 252 which is the tuner amp
version and the CXA seems to be a slightly more powerful
version (but no external heatsinks all active in totally enclosed
metal case) of the output modules used in the CTA 252.
So far so good . Now more that doesn't hang together
-incredibly thick guage (electic cooker wire) used for power
wiring inside but 2 pairs of outputs thin wire connected
to crappy 2 pin din (low power) speaker sockets.
THe legend on the outside says for use with ARC 'B'
speakers.
A pre-amp ? low power output ? daughter board
is also marked ARC 'B'
One output channel goes to parallel paired up
4mm banana sockets with one 2 pin Din
socket labelled 'L. F OUTPUT' and the other channel
to 'H. F OUTPUT' banana plus din , not left and right ouputs. Two
pairs of outputs but 2 each paralleled together -
what is this nonsense about ? . I don't think anyone
has ever been inside this amp and rewired or repaired
at any time since manufactured

e-mail (removing .....) diverse2@tcp.co.u.....k
electronic hints and repair briefs , schematics/manuals list on
http://homepages.tcp.co.uk/~diverse

Nigel,Diverse Devices,Southampton,England

 

[Nigel Cook]

"Nigel Cook" <diverse2@tcp.co.antispam.uk> wrote in message
newscOdnS3hqrDRdTmi4p2dnA@tcp.co.uk...

Also for the archives CXA252.
Very little on the www about this except someone else
who seems to have been here before but no resolution.
I wish to confirm this 1980 ? amp has not been tampered with
before i power-up and repair.
I have the schematics for the CTA 252 which is the tuner amp
version and the CXA seems to be a slightly more powerful
version (but no external heatsinks all active in totally enclosed
metal case) of the output modules used in the CTA 252.
So far so good . Now more that doesn't hang together
-incredibly thick guage (electic cooker wire) used for power
wiring inside but 2 pairs of outputs thin wire connected
to crappy 2 pin din (low power) speaker sockets.
THe legend on the outside says for use with ARC 'B'
speakers.
A pre-amp ? low power output ? daughter board
is also marked ARC 'B'
One output channel goes to parallel paired up
4mm banana sockets with one 2 pin Din
socket labelled 'L. F OUTPUT' and the other channel
to 'H. F OUTPUT' banana plus din , not left and right ouputs. Two
pairs of outputs but 2 each paralleled together -
what is this nonsense about ? . I don't think anyone
has ever been inside this amp and rewired or repaired
at any time since manufactured

e-mail (removing .....) diverse2@tcp.co.u.....k
electronic hints and repair briefs , schematics/manuals list on
http://homepages.tcp.co.uk/~diverse

Nigel,Diverse Devices,Southampton,England

This must be the craziest amp i've ever come across.
Fixed the relatively straightforward problems that
could not influence the functioning described and
could power up both parts.
On its own the CTA with a preamp - amp bridge
on the o/p & i/p 5 pin din works fine.

On its own the CXA only seemed to work on left
channel but connect CXA to CTA via the cross-over
type 5 wire 5 pindin to 5 pin din then it does work
The other channel goes and returns down this link
it would seem ,part tracing the wiring.
Unfortunately the owner has the speakers that go with
this setup in another part of the country. But ,yes, stereo
output of sorts (in mid range ) from the CXA all bass
and mid from the pair of o/ps
marked LF and treble and mid from the HF pair.
Balance on the CTA is ineffective in this mode
and volume very much at the bottom of the control.
Anyone coming across a pair of ARC 'B' speakers
will have a mystery on their hands as well.
Weird or what ?????
I think a post to a hifi nuts NG is in order

e-mail (removing .....) diverse2@tcp.co.u.....k
electronic hints and repair briefs , schematics/manuals list on
http://homepages.tcp.co.uk/~diverse

Nigel,Diverse Devices,Southampton,England