This is probably one for Arfa.
An old friend asked me to take a look at his Roberts Radio R303, I`d usually say no, but, well you know how it is!. It's not oscillating, I imagine it's the old AF114 promble, shouldn't be too much trouble to mend, but how the hell does one get the chassis out of the case? The only way seems to be to take out the battery cradle and speaker, which looks difficult with the circuit board in the way, or am I missing something?
Ron
Perhaps one of the first solid state repair "fixes". If a 4 pin can, cut the pin connected to the can. Nothing to loose , can always resolder if something else. Never did find the reason fo rthe internal short, metalisation creep?
-- Diverse Devices, Southampton, England electronic hints and repair briefs , schematics/manuals list on
Hi Ron
What Mr Cook says below on the problem and its 'fix'. I actually used to 'blast' the internal short off the transistor, by momentarily shorting the transistor base to collector :-) ...
On getting the chassis out, is it by any chance one of the ones where the top part is secured into the case by screws at either side, which are also the handle pivots ? If so, the handle clips off on spring-loaded 'keyholes' and then the pivot pins revealed have a screwdriver slot in them. Once removed. the radio withdraws from the top. Could be thinking of an entirely different model of course. Old grey matter is not what it once was ...
Arfa
Thanks arfa, I`m aware of the AF114 internal shorts, even way back in the late 60`s it was happening, sometimes flicking them with a finger nail would get them fired up again, temporarily at least. I used to snip the screen wire.
The top of this radio seems to be glued to the case, the handle is fastened on with spire clips directly to the wood, the chassis is held in by two thin plywood strips in grooves, removing these allows the chassis to slide backwards (downwards) but obviously the speaker is in the way, the lower nuts holding the speaker in are somewhat inaccessible with the chassis in the way.
Ron
be
of
which
the
the
also
'keyholes'
entirely
from 67 Newnes loosen battery bracket remove speaker remove woodscrews on chassis sides slide chasis out
Aye thanks for that, Having a feel around with a finger (ooer missis) I realised that the speaker only has two nuts at the outer edge, so it shouldn't be a bad job
Ron
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