Note: I don’t sell parts. My inventory is for repairing my customer’s radios only.
Frankly, I shouldn’t have to publish this article. But unfortunately, some folks, as well as some pack-and-ship stores, fail to properly pack these radios for shipment.
When these rigs are not packed properly, their dual-concentric potentiometers (pots) are quite vulnerable to damage.
If the radio is not secure in its packaging and/or there isn’t enough protection of its front-panel, the weight of the radio bearing down on the front-panel controls can cause these pots to crack.
The following front-panel controls can be damaged:
IC-746: AF/RF/SQL and NR/APF
IC-746PRO: AF/RF/SQL and NR/NOTCH
IC-756/PRO/II/III: AF/RF/SQL and BAL/NR
These pots are no longer available. But I’ve acquired some suitable replacements, which are electrically identical. But they must be wired in. And the inner knob must be replaced with a different style.
See the pictures below for details.
A damaged pot shown on the left, and an undamaged pot on the right:
An original pot shown above a replacement type:
An original pot shown above a replacement type, with knobs:
Mike Nadeau – N1EQ
September 25, 2019