[R-390] RF deck removal

[Craig Heaton]

Sort of from memory:

Find two short blocks of wood to raise said radio a tad. 
Remove top & bottom covers.
Remove Oldham spring.
Reaching in with a very long Philips screwdriver, remove green head screw
which holds clamp/wire harness just above the local gain pot. Use hole in
bottom left front of RX.
Remove IF deck. 
Place wood blocks/etc under said receiver; set receiver frequency to 7 +000
Drop front panel, if you got the correct clamp in above step there will be
more than enough slack to drop front panel.
Next is the crystal deck; remove coax connectors from antenna relay which
are behind the crystal deck. You will have to rotate one of the gears to get
to one of three green head screw on the front of the crystal deck. Loosen
clamp holding said crystal deck shaft. Slide deck back towards antenna relay
and remove.

At this point, attack the RF deck with vengeance. Remove all green head
screws, spacer from Oldham coupler will fall free from the PTO. It should
remain on workbench.

YMMV

Craig, 

-----Original Message-----
From: R-390 [mailto:r-390-bounces at mailman.qth.net] On Behalf Of Alan Victor
Sent: Friday, October 10, 2014 2:43 PM
To: r-390 at mailman.qth.net
Subject: [R-390] RF deck removal

In the Y2K manual and the Army TM the instructions for the removal of the RF
sub chassis have you remove the Oldham coupler backlash spring first. Then
remove the front panel following the procedure in a previous paragraph. In
that previous paragraph the KC knob is to be rotated fully CCW to -963.
QUESTION: Why not do this first and then remove the backlash spring. Does it
matter? Not knowing any better,  it would seem I run some risk turning the
KC knob with the backlash spring removed.
Is the pressure present on the pressed couplings sufficient that this is
just not an issue? Or if I rotate to -963, I cannot get to the backlash
spring readily?

One last item. I notice in the TM a CAUTION that during the removal of the
RF sub chassis, the Oldham coupler on the VFO shaft will come apart and the
center disk will fall to the bench. I can see my luck, it will fall on the
floor never to be found! This item is not in the Y2K manual, perhaps because
it can be handled in a better way? Or there is typically so much grime and
grease that it just does not fall off.

Comments?

Thanks again in advance!
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