> On Oct 9, 2017, at 10:20 AM, jimlux <jimlux@earthlink.net> wrote: > > I'm trying to come up with a relatively simple scheme to calibrate an HF antenna array - I've got a bunch of RTL-SDRs operating as a distributed array spread over a few 10s of meters. > > In terms of frequency, I think it should work fairly well - I tune the > RTL's front end, look for my calibration combs that are "in band" and fit > an appropriate function to the signal (there should be a well defined phase > relationship between the harmonics) > > So ****************************************** Also have SDR here. Interestingly the issue I found is you do need a good fast PC or packets will get lost. I use a quad core Phenom with 8GB and it still loses data as it's highest sample rate resoldering USB helped somewhat. I have a Tektronix 015-040 5mV/mA CT if someone has a use with pigtail lead and screw end. Has non standard fitting Andre