2019-06-12

Pipe Caps Received. Filters for 2.4 and 10 GHz.

I am just back from some non ham radio related travels.
I have received some copper pipe caps, suitable for making simple filters for the 2.4GHz and 10GHz bands, and a length of semi-rigid coax cable.
On the way: 2009MHz LO modules, can be modified for 1968MHz (2400MHz TVTR LO for 432MHz IF) or possibly 1960MHz  (for 439MHz IF) with an added PLL or DDS in place of the internal XO.

I have been reading up on articles about those filters, and it looks possible, even with my not too good skills in mechanical construction, to make a few filters.

Finally, I also found a filter with a centre frequency of 2375MHz and bandwidth of close to 300MHz. This could be suitable for a transverter with 432/439MHz etc IF. I knew I had it, but could not find it before, due to the mess of moving.

The equipment necessary to test the filters for 2,4GHz filters I have. It is the MiniVNA vector network analyzers, covering all bands from a few 10s of kHz to 3GHz.

For the 10GHz filters I will have to rely on a simple signal generator like the HB100 radar module, possibly modified, and a microwave uW/mW meter.
A friend had made one with about 60-70dB range, and I intend to use that. It only provides a simple tuning aid, but I think I can get access to some better test equipment at a local ham with an extensive set of test equipment, for better alignment of filters.

Things are slowly starting moving.


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