1st post please be gentle with me... :-SI have a home brew SW transmitter to which I have converted to operate on the commercial mw band..I only have a couple of crystals...Years ago there was a company in the uk who would cut them to order...Can't find a company that does that these days...Can anybody shed any light please?....The rig uses an el84 as a driver and 1 807 valve for the pa...cheers
No idea, but it may not be too hard to use a frequency synthesizer circuit. I know some places like digikey sells those ones with the DIP switches to program the frequency. They probably have a square wave output though so not sure how well that would filter through the other transmitter stages. I know there are companies out there that will make you a crystal to the frequency you specify but it will probably cost a bit of coin.
I use my kenwood ts140 tx/rx to modulate above 1.6mhz....I could I suppose build a pll circuit but as I only want to transmit on a few frequencies and the availability of clear channels is limited i think a couple of xtals would be less hassle.
Could you let me know the companies that cut to order please?...Another quick question... The place in Greece RF Source sells some good kit and I have tried to email and phone the company but get no response,is he still trading?..
Cheers...catch u later keep up this excellent forum...I'm wading through all the posts with great interest
Why bother with crystals these days? Synthesisers are cheap and easy to build. You just need one reference crystal (usually a £0.40 standards part from CPC) and some cheap CMOS logic. I build synthesisers for MW for just a pound or two's worth of parts - cheaper than even one specially cut crystal. Incidentally, most of the crystal companies will report your request for MW rocks to the authorities!!!!
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