Gents:
I received the ICs for the 87A upgrade today and thought I'd pass on a
potential problem with the installation. I hasten to say that this isn't an
Alpha Power problem but a potential 'gotcha' if you don't do it quite
right.
When you remove the screws holding the front panel to the main chassis and
ease it forward, the next step is to uncouple a number of connectors to
remove it completely. One of these is a red four-pin near the top centre of
the panel. This isn't indexed, and when you've changed the ICs it's very
easy to replace it one pin "down" from where it should be. If you do this,
the result is a frying noise, a bad smell from within and the burning-up of
a trace on the vertical PCB at front right which holds the reservoir
capacitors.
Yes, I did find this out the hard way. Yes, I do feel exceedingly silly. As
the aviators say, "don't assume, check". I thought I had checked, but
clearly not well enough.
73 John :-(
GW4FRX
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