From: [email protected] <[email protected]> on behalf of Jason VK7ZJA <vk7zja@...>
Sent: May 1, 2022 11:14 PM
To: [email protected] <[email protected]>
Subject: [Yaesu-FRG-7] Issue with 1MHz not locking

Hi all,
My recently restored FRG-7 has developed a slightly annoying problem.? When cold, the 0, 1 & 2 MHz bands won't light up the 'lock' LED.? After some time warming up, the 0 & 2 MHz bands will lock, but the 1 MHz band never does.? However, at all times, if I centre each MHz selection, the receiver works quite OK on all those bands, receiving signals just fine.
When going through the restoration, I replaced most capacitors - electrolytic, mylar / greencap / polyester - but not any of the disc ceramics.? Q102, 103 & 105 were replaced, too, but that shouldn't have any bearing on the lock LED lighting on some bands and not others.? I realigned the FRG-7 back about 6 months ago, and all was fine then.

The problem is likely to be either with the comb generator Q301 / D301 / D302 not producing enough level down around 3-5 MHz, or the 1st oscillator Q201 not producing enough level down around 55-57 MHz, or perhaps an issue with the mixer Q106.

Maybe VR102 is simply just set too fine?? Before I go ripping into the radio and checking levels from the 1st osc or comb generator, has anyone else experienced this issue, and recall what the cause was?

Thanks,
Jason