AR88 - the continuing saga...
Thanks to those who've responded so far (including direct to my email
address) and for the rest of you who've put up with my ramblings.
I now have two more requests for help. 1) I am missing the outer RF
screen (that goes over the RF valves and inner screen containing the
variable condenser). No-one seems to have a spare so I must get one
fabricated. Can some kind AR88 owner measure up their RF screen accurately
so that I can do a drawing for a quote.
Second request: I need the two trimming tools (who doesn't!) I assume
no-one here is going to offer me one so I would like to have them made or
make them myself. Again could someone measure up for me or even tell me what
*they* did to improvise.
Have already taken steps to build a wobbulator and get an old scope so I can
emulate those waveforms in the manual.
Perfection then only needs the original S meter as fitted to the AR88 before
it became the D or LF... I dare not hope for that but I should think a
skillfully made replica might find a good market. The movement is 5 mA,
right hand zero, and in the instructions (from the EMER documents, found on
the VMACS website) there is a preset pot for adjustment. It should not be
hard to make the dial realistically...
This will be the next job after solving the grid bias problem (subject of
earlier post).
Thanks and regards
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