Frequency measuring question
Posted: Mon Dec 16, 2019 7:33 pm
I have been noticing some errors when measuring frequencies when using my 7000, phase display, and DSB function.
My 7000, and HP 3336 sig gen time bases are synced to a lucent ks 24361 gpsdo unit.
When I input a sig (5100 khz) from the generator the trace dot should not rotate as the sg and 7000 time bases are synced with the gps The dot does not move. Good!
Inputting 5000 khz the dot moves - changing the sig gen fx to 4,999,999.980 (-20 milliHz) the dot does not move.
Just wondering why some frequencies do not move and others do. To stop the rotation on the moving ones lowering the input fx by -20 milli hz works. I have reset database and reinstalled existing db and tried three other sig gens and they all play the same.
It is no big deal. I was just playing around with the gear and saw this problem. Again wondering why it was happening.
Part of my business is measuring frequencies for clients. I started doing this 40 years ago when broadcast stations had to have their fx measured each month to keep FCC happy. That is not needed any more but still have some clients that need it done.
My fx measuring rig is an HP 3336 level gen, 3586B selective level meter, Lucent GPSDO, and a tek 475 scope.
Also a member of the FMT user group. Gotta get a life.
Check out my call WA2DVU on qrz.com for some pics.
I would imagine the error is somewhere in the 7000 synth but again no problem with normal operation of the rig.
73, Bill WA2DVU
Cape May
My 7000, and HP 3336 sig gen time bases are synced to a lucent ks 24361 gpsdo unit.
When I input a sig (5100 khz) from the generator the trace dot should not rotate as the sg and 7000 time bases are synced with the gps The dot does not move. Good!
Inputting 5000 khz the dot moves - changing the sig gen fx to 4,999,999.980 (-20 milliHz) the dot does not move.
Just wondering why some frequencies do not move and others do. To stop the rotation on the moving ones lowering the input fx by -20 milli hz works. I have reset database and reinstalled existing db and tried three other sig gens and they all play the same.
It is no big deal. I was just playing around with the gear and saw this problem. Again wondering why it was happening.
Part of my business is measuring frequencies for clients. I started doing this 40 years ago when broadcast stations had to have their fx measured each month to keep FCC happy. That is not needed any more but still have some clients that need it done.
My fx measuring rig is an HP 3336 level gen, 3586B selective level meter, Lucent GPSDO, and a tek 475 scope.
Also a member of the FMT user group. Gotta get a life.
Check out my call WA2DVU on qrz.com for some pics.
I would imagine the error is somewhere in the 7000 synth but again no problem with normal operation of the rig.
73, Bill WA2DVU
Cape May