UK Vintage Radio Repair and Restoration Discussion Forum - View Single Post - Pye T30FM transmitter and R17/R18 receivers

Jon_G4MDC · 9th Mar 2018, 6:27 pm

Very good Peter. I think you will find that FM Westminster crystals will suit them.
Double check by reverse calculating the ones already fitted if there are any.

TX will be 4MHz for 2m, Fc/36, 30pF Parallel will usually be fine.
RX will be 45MHz for 2m, (Fc-10.7)/3, Series resonant 3rd Overtone.

Most Japanese rice box crystals are fine for the RX but their TX ones are more often
12,16 or 18MHz.

I too like that front end box. Tip is to inspect the copper sheet inside the lid.
It needs to be clean and mate well with the dividers in the main chassis.
I have increased sensitivity by 6dB just by rocking the lid on these!

9th Mar 2018, 6:27 pm	#5
Jon_G4MDC Nonode Join Date: Nov 2015 Location: Welwyn Garden City, Hertfordshire, UK. Posts: 2,015	Re: Pye T30FM transmitter and R17/R18 receivers Very good Peter. I think you will find that FM Westminster crystals will suit them. Double check by reverse calculating the ones already fitted if there are any. TX will be 4MHz for 2m, Fc/36, 30pF Parallel will usually be fine. RX will be 45MHz for 2m, (Fc-10.7)/3, Series resonant 3rd Overtone. Most Japanese rice box crystals are fine for the RX but their TX ones are more often 12,16 or 18MHz. I too like that front end box. Tip is to inspect the copper sheet inside the lid. It needs to be clean and mate well with the dividers in the main chassis. I have increased sensitivity by 6dB just by rocking the lid on these!