Frequency mulitplier chains in PYE Receivers (R7AM)

I bought an R7AM as a "pig in a poke" off eBay a while back it was originally setup up for 106MHz. I thought I'd move it up a bit.

The oscillator multiplier chain is 3rd overtone cristal followed by x2 x2.

I had a 3rd O/T cristal to hand that I thought would work if I went for x3 x1. The transistors in the mulitplier chain are ft 800MHz and I thought would go at c120MHz but they insist on sticking at x2 (assuing the frequency counter isn't telling lies - its a real ex RAF one) even though the coils are dipping nicely at the x3 freq before I power up. My scope won't stretch to these sorts of frequencies and the wavemeters not convinced either.

The cristal oscilator is working fine and peaks nicely on the scope and it's running at the correct frequency, so nothing odd there.

My assumption was that it would be easier to run the multiplier at an odd harmonic than an even one, but can't see the problem here.

Just a bit of fun, but didn't expect the multiplier to refuse to step up though. Any thoughts on what's going on?

Steve
G0AIN


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