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View Full Version : Has anyone ever added a course/fine clarifier to a 148GTL or Grant-XL?



Shaky
08-17-2022, 05:39 AM
Has anyone ever added a course/fine clarifier control to a Cobra 148 or Grant-XL (or similar rig)?
Normally they have a regular single control but I'd like to add a dual potentiometer course/fine control like a Cobra 2000 and similar radios have?

I used to have a Cobra 148GTL-DX years ago that had the dual control. My Cobra 2000 also has it and since it basically has the same board as a 148, I'm wondering if I can copy it over to my mobile rigs?

According to the schematic, the 148GTL-DX has a 20k/1k dual potentiometer. I believe they are called a 'concentric' pot. My Cobra 2000 has the same type, but I can't find one under its original part number. I've found other dual-shaft pots with the right value, so I don't think it really matters so long as it fits in the radio. Wiring it on the other hand - might be tricky. I'm hoping someone with greater 'screwdriver' knowledge than me can help?

While I can always use a precision pot for fine control, it can be a nuisance in a mobile rig. I love the sensitivity the 10-turn brings, but it can be a hassle. A 3-turn might be more ideal, but a frequency counter is almost a must. Finding a 3-turn in the right value is also difficult.

I'm hoping I can convert it to the course/fine. I really liked it in the 148-DX.
Ideally if there was a dual pot that had the normal 20k and then a precision 3 turn would be epic, but I don't think something like that even exists.

Thanks,

PS: Does anyone know who makes this potentiometer or ones like it?