Frequency offset Calibration

EduardoCarvalho

I have tried to use the frequency calibration function in SmartSDR and I have not been successful. Every time I perform the calibration it finds a different offset that needs to be set to. My biggest concern is the fact that every other time I calibrate it it goes back to 0, and it alternates between a value and 0. 

This feature never appeared to work for me, but I finally just got around asking about it after a year of having the radio.

Is anyone experiencing the same issue?

Thanks,

Eduardo, KC8R

Ross - K9COX

I have noticed the same results and have just considered it an useless feature.

dl9eri/oe9eri

It is absolute n o t  a useless feature, and it works at best when known how to use it !

I here in Europe do not use the 15MHz calsignal, because it is to week here, I have an
HP Signal-Generator and 10Mhz stability from GPS and set it to 15Mhz with abt -60dBm
and then calibrate the Flexradio from time to time. At present my number is around -770
but this number will be different for each radio.

73

Jim KJ3P

I have the same problem with my 6300.  I tried using the various WWV frequencies when they were very strong, but no joy.  Fell back to using the old upper/lower sideband tone comparison technique, and setting the value by ear.  Using test equipment as another person has mentioned may be a work-around, but the function still does not work as intended for those of us without such equipment.

Mike - AG6BF

I hope you are aware that you can manually input the cal offset number and shift the carrier until it matches the calibrating frequency. This is useful in weak signal conditions and I can get + or - 1 Hz with little problem. Expand the  spectrum display for maximum resolution. For the 15 MHz signal I use USB with a frequency step of 1 Hz. changing the offset number by 1000 will change the frequency by 16 Hz (approximately). So if you are indicating 16 HZ high on your Frequency indicator add a value of -1000 to shift the frequency by 16 Hz. The amount of shift is linear so -500 will shift by 8 Hz. I use this method and it seems to work fine. If anyone has different results please let me know.

Mike, AG6BF

EduardoCarvalho

Mike, thank you for the feedback. I was aware of the capability to change it manually, I have used that method but it can be a bit tricky due to the instructions you just provided. I think the manual offset should have a reference there, ex: 100 ppm = 1Hz, to help us out. 

However, I just wish the feature worked as advertised. I am only using this feature with WWV. 

Another item that I think it may help is if it would stay in frequency for a bit longer than a few seconds for the calibration. The process seems to be really fast and maybe that is why I am getting inconsistent calibration results.

Eduardo, KC8R

Tim - W4TME

There is a defect in the way the frequency calibration routine works and it will be fixed in the next release of SmartSDR.