The BFO VCV problem was described in the FOX TANGO newsletter in about 1984.? Thanks to N8TW for pointing this out.? I replaced the trimmer in my first FT-980 I bought in 1983.? That GT-980 is running strong at N4PL. Thanks to N8TW to pointing to the .Yaesu Tech Supplement page covering this...
Being out of range means the FT-980 does not receive.? The first notice of a problem is that the tone is not the same on LSB as on USB.? Thank goodness it is an easy fix,
-----Original Message----- From: <[email protected]> Sent: Sep 21, 2021 6:07 PM To: <[email protected]> Subject: Re: [Yaesu-FT-980] FT980 dose not recieve
I had to eventually replace this capacitor, as the original drifted completely out of range. It is very common. The capacitor is TC4001 ... it is located under a "can" with a hole to adjust.
You can see if it is operating by putting a voltmeter on TP4004 (right near the cap): it should read between 3V to 6V depending on USB/LSB setting, and IF-Shift position.
The adjustment procedure is called "BFO VCV", and you can find it on page 23 of the Technical Supplement in the files section.