Buy an nanoVNA from a reputable dealer like R&L and follow the manual procedure. Twice. The circuits interact so the 2nd pass is to compensate for that. You're unlikely to see significant change on the 2nd pass, but it's a good feeling to see all the test points as they should be.
On Tuesday, May 30, 2023 at 09:18:31 PM CDT, Pentagrid <dayleedwards@...> wrote:
I am beginning to think this radio is actually fine, it has been misaligned.? The VFO, "mHz tuning" should span from 55.5 to 84.5 mHz.? The first IF should be centered on 55 mHz, this can be checked by feeding in a small signal into the IF chain and monitoring the output at the second mixer. The Wadley loop section should be centered at 52.5 mHz, this is checked at the source of the second mixer.? The difference frequency between 55 mHz and 52.5 mHz is 2.5 mHz, the center frequency of the second tuneable IF.? When peaking/adjusting these IFs, use a very low amplitude signal as not to overload any part of the circuitry. Its just a process of elimination and perseverance........
