UK Vintage Radio Repair and Restoration Discussion Forum - View Single Post

Jon_G4MDC · 3rd Aug 2018, 6:15 pm

Interesting, either I have one with an internal crystal or I have just the box having the internal crystal as a spare. Evidence long gone if it is the latter.

Will remember to look at it next chance I have.

Yes washing the crystal from the plug in one is usually beneficial.

It's also instructive to pick off some IF from the box and feed it into a DSP dongle
SDR. Set for 1 MHz bandwidth it shows very nicely how well the coil box tracks across the dial. If the noise bump stays centred on 456k across the whole range you are doing well.

One of mine crossed over completely.

3rd Aug 2018, 6:15 pm	#42
Jon_G4MDC Nonode Join Date: Nov 2015 Location: Welwyn Garden City, Hertfordshire, UK. Posts: 2,015	Re: HRO and BC348 Interesting, either I have one with an internal crystal or I have just the box having the internal crystal as a spare. Evidence long gone if it is the latter. Will remember to look at it next chance I have. Yes washing the crystal from the plug in one is usually beneficial. It's also instructive to pick off some IF from the box and feed it into a DSP dongle SDR. Set for 1 MHz bandwidth it shows very nicely how well the coil box tracks across the dial. If the noise bump stays centred on 456k across the whole range you are doing well. One of mine crossed over completely.