stephenkearney
New Member
I received the ADF4351 signal generator board yesterday and have been playing around with it. Doing antenna return loss measurements works okay but I haven't figured out a good way to sweep frequencies. The Analog Devices app does have a sweep function but it appears the 4351 only outputs a very narrow bandwidth signal and it needs ~1 sec. to step to the next frequency increment. I'm still looking for a good way to get that slow sweep to sync with the RTLSDR spectrum analyzer. For now it seems like a better to use SDR# to check return loss at the desired frequency. If it's acceptable (e.g. -10dB) then do some spot checking of the return loss at a few points above and below the target frequency.
I did find that the 1090 MHz monopole I made from music wire is terrible: -1.5 dB return loss or a 71% loss of power
BTW the 4351 board came with a bad USB cable. If you have trouble getting Windows to recognize the USB device that's likely the problem. I wasted an hour fiddling with it before trying a new cable.
I did find that the 1090 MHz monopole I made from music wire is terrible: -1.5 dB return loss or a 71% loss of power
BTW the 4351 board came with a bad USB cable. If you have trouble getting Windows to recognize the USB device that's likely the problem. I wasted an hour fiddling with it before trying a new cable.
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