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Determine best values of VFO_A and VFO_B


Bob Shaw
 

I am currently using 1.080 sketch and MM 1.081 on a WIN10 PC.

Can anyone explain how to determine the original values of VFO_A and VFO_B that may have been accidentally changed? I believe this accidental change may have reduced the uBitX sensitivity greatly (or are the bands really this bad)!  Currently, these values are decimal 26, 211, 53, 00 and 16, 62, 17, 00 In my uBitX.

I wonder if VFO_A and VFO_B are really only the current user VFO settings, and not really critical to the uBitX's "magic numbers"? Or was the warning not to change these magic values referring to MASTER_CAL, LSB_CAL, USB_CAL and SIDE_TONE? Currently these values are set to all zeros in my uBitX. Perhaps these are the values I need to recalculate. I can't find enough information to decide what to do at this point.

Any help greatly appreciated.         Bob VA7SU


Ralph Mowery
 

VFO A &  B does not matter.  Those are just where the frequencies are when you tune a station.  

The other ones are what you need to adjust .Those values should not be zero.  Hopefully you saved the original program and can load it back in.  Then do the recalibration.  If not try to find a strong station of a known frequency such as a local AM broadcast if nothing else.


On Tue, Jul 10, 2018 at 3:54 PM, Bob Shaw <ve3suy@...> wrote:
I am currently using 1.080 sketch and MM 1.081 on a WIN10 PC.

Can anyone explain how to determine the original values of VFO_A and VFO_B that may have been accidentally changed? I believe this accidental change may have reduced the uBitX sensitivity greatly (or are the bands really this bad)!  Currently, these values are decimal 26, 211, 53, 00 and 16, 62, 17, 00 In my uBitX.

I wonder if VFO_A and VFO_B are really only the current user VFO settings, and not really critical to the uBitX's "magic numbers"? Or was the warning not to change these magic values referring to MASTER_CAL, LSB_CAL, USB_CAL and SIDE_TONE? Currently these values are set to all zeros in my uBitX. Perhaps these are the values I need to recalculate. I can't find enough information to decide what to do at this point.

Any help greatly appreciated.         Bob VA7SU



Bob Shaw
 

Thank you Ralph for your reply. I have MASTER_CAL as 92 68 00 00 from an attempt to calibrate by zero-beating an AM broadcast station. Is there any procedure to get new values for LSB_CAL, USB_CAL and SIDE_TONE that you know of? I do have a GSP referenced  RF signal generator.  Too bad there wasn't a warning about these values with the uBitX, or perhaps these values printed on each board, since they are so important yet vulnerable to loss.     Bob VA7SU


Ralph Mowery
 

If you go here you will find all you need to know about the caoibration.




On Wed, Jul 11, 2018 at 12:59 PM, Bob Shaw <ve3suy@...> wrote:
Thank you Ralph for your reply. I have MASTER_CAL as 92 68 00 00 from an attempt to calibrate by zero-beating an AM broadcast station. Is there any procedure to get new values for LSB_CAL, USB_CAL and SIDE_TONE that you know of? I do have a GSP referenced  RF signal generator.  Too bad there wasn't a warning about these values with the uBitX, or perhaps these values printed on each board, since they are so important yet vulnerable to loss.     Bob VA7SU