Yaesu FRG-7700, Survival Manual

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PAØPGA
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The S-Meter was also not functioning properly, and after taking it out, I saw that the movement was just a block of rust.
I cleaned it as far as possible, but the needle stuck every now and then, so I suspected a broken movement, or the coil
out of his bearings.
While I had the meter out, I searched my junkbox, and found a VU meter from an old cassettedeck, which was a near-
perfect fit. I checked the resistance of the movement and even that was almost the same. I swapped the meter scale,
and put the meter back. The only change was the connection, it was reversed on the new meter.
The FRG-7700 was now working again, so I did a tune-up according the manual, surprisingly, it needed not much re-
alignment.
Compared with my other FRG-7700, the signals were almost the same strenght, so I spended some time to clean the
chassis, knobs and frontpanel, and rebuild the set.
After rebuilding, I will try some modifications, to improve selectivity and test some ideas of my own, like a clarifier,
improve sensitivity for the AM bands and others.
Modifications:
Fine tuning:
One of the things I missed on this receivers is a small RIT control or fine tuning, a very handy device when I am
listening in on a net or ragchewing Hams.
The ragchewers are not always at exactly the same
frequency, and constantly tuning with the main dial is no
fun, because you easely overcompensate, losing all
information. The main dial can be set exact enough, but
not quick enough to follow quickly changing talk.
A FRG-7700 with a memory unit has no problem with that,
you tune in, push the Memory button and then Memory
read. You can then tune around the frequency with the
Memory fine knob.
After studying the circuit diagram I found that the Memory
Fine potmeter is nothing more than a voltage divider, the
output is used to tune a varicap in the memory unit.
Well, why not tune a varicap in the VFO with the existing
circuit ? I did it this way in a home brew transceiver some
25 years ago, and that worked fine.
So I took the VFO out the receiver, a very easy job,
altough it means the removal of all knobs, scales and front
panel. Be careful with the lampholder on the VFO, (see
above!!), disconnect everything, including the power cord.
The changes in the VFO