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John G8MWF · 4th Oct 2019, 8:19 pm

Thank you all for the input and good ideas.

I made some progress today getting the 'scrapper' partially working on the rx side.
I have two chassis and the scrapper is the chassis that I am using to try out different options.
It has been heavily modified in the past and some of the tx modules are missing whereas the other chassis is still very close to original.

One of the rx xtals, around 51.4Mhz, from the 'good' set was placed in the scrapper and tuned up. This was achieved by listening on another handheld tuned to the local oscillator frequency which is 10.7Mhz above the rx frequency - a surprisingly quick and practical method!!

Interestingly the tuning slug in the 1st local oscillator was quite a way out of the holder which hopefully means that it will tune down to a lower xtal frequency, 49.30556Mhz, for the 70cm band.
It could just be that this module has already been modified in the past but I don't want to pull it apart and risk damaging it.

Hopefully this will be successful and it would be very nice to get to use a proper signal generator to line it up as best as possible.
All of the factory colour codes show that it is/was a high band set and it may be a bit deaf when using it on the lo band frequencies.

4th Oct 2019, 8:19 pm	#13
John G8MWF Hexode Join Date: Aug 2014 Location: Dartford, Kent, UK. Posts: 435	Re: Modifying Vintage PMR Coils Thank you all for the input and good ideas. I made some progress today getting the 'scrapper' partially working on the rx side. I have two chassis and the scrapper is the chassis that I am using to try out different options. It has been heavily modified in the past and some of the tx modules are missing whereas the other chassis is still very close to original. One of the rx xtals, around 51.4Mhz, from the 'good' set was placed in the scrapper and tuned up. This was achieved by listening on another handheld tuned to the local oscillator frequency which is 10.7Mhz above the rx frequency - a surprisingly quick and practical method!! Interestingly the tuning slug in the 1st local oscillator was quite a way out of the holder which hopefully means that it will tune down to a lower xtal frequency, 49.30556Mhz, for the 70cm band. It could just be that this module has already been modified in the past but I don't want to pull it apart and risk damaging it. Hopefully this will be successful and it would be very nice to get to use a proper signal generator to line it up as best as possible. All of the factory colour codes show that it is/was a high band set and it may be a bit deaf when using it on the lo band frequencies.