Total posts : 45366
I have my Motorola RD2012 and HP 8590 calibrated every year at a considerable expense. The RD2012 serves as both my FIM, modulation meter and frequency counter, amongst many other neat things it can do. And the HP serves as my spectrum monitor watching for any spurs and junk that may crop up.
I have a B&K frequency counter I salvaged from a closed down TV repair shop and I rarely use it, but so far it has kept its accuracy within a few ppm’s of the specs. Good enough for quick checks and initial designing, but the Motorola RD2012 unit is my be all end all device that tells me what is truly going on.