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Farhan sent me a uBitx about a year ago.? Mostly assembled and the final assembly went without a hitch.? Very nicely done!? Seemed to tune the bands.? Put out RF as expected.? Drew about the right amount of current.? But my antenna situation was an impossible solution.? Our 0.2 acre lot has no trees.? No room for an elegant solution.? HOA restrictions galore.?

This week I was able to secure a fiberglass vertical element.? 18' - 4" of wire hidden inside was easily fitted to the 6' high privacy fence with a counterpoise and some matching it tunes perfect.? Moved to the back porch and got all set up with my nifty little uBitX v6.1 and paddles and set out to land some QSOs.? I've worked QRP in contests and casual QSOs and expected to work stations.? Nothing.? Callers CQing away simply ignore me.? Hours spent and no joy.?

Grabbing the ATS-25 receiver, I discovered why.? It transmits 2.4 KHz off my receive frequency.? Spent the better part of the afternoon attempting an "alignment' using the setup menu.? I can move the transmit frequency somewhat and sort of understand how the radio is supposed to work.? But using the setup routine requires that I move the setting to over 800,000 and still not able to zero beat.? Going beyond 800,000 causes the receiver to shut down.? Signals disappear as if I'm moving it beyond the 45 MHz roofing filter.? Somethings not right here.?

My question is, how to proceed figuring out a solution.? Is it possible that the 45 MHz filter is wrong?? How about the 11MHz filter?? I've tried using the RIT and various LSB / USB settings.? I just cannot get it right.? The radio is working.? It's just not usable until I can figure out how to transmit on the right frequency.

I was hoping to use it on Field Day.? Short of acquiring an actual radio that works, that it looking doubtful.

Any good ideas for me?

Ford-N0FP

Hi Ford,

Did you follow the procedure in this video?


You should note that the original software loaded in the uBitx from the factory offsets the transmitted frequency by the sidetone setting.? There are other software programs available that, instead of offsetting the transmitter frequency, offset the receive frequency either up or down depending on the CW or CWR setting.

Be sure to do all of the steps in the video.? The first BFO setting is to adjust the receiver's response to hear the lowest tone possible for zero beating.? The second step sets the master clock, and the last step readjusts the BFO for the best response to voice and carrier suppression.

I would calibrate the radio per the video, then load any new software if you want a different performance.? My preferred is in the files section of this list server:
/g/BITX20/files/uBITX_6_N8ME_2_VU3GAO_Mods.zip

73
Evan
AC9TU

An alternative for getting on frequency might be to tune in a strong AM radio station in your area that you know the frequency for.? You set your displayed frequency to the exact station frequency in sideband mode to start, then use Set Freq mode to change the frequency until the sound is clear.? ?When the tuning is right on, you should be able to switch between USB and LSB without any significant change in the sound quality (since it's AM).? Keep in mind the stock software has a minor bug that requires you tune the frequency slightly off then back after you change the sideband to actually get the sideband to change in the receiver after touching a sideband button.

If you have a good frequency counter available, you could set your displayed frequency to say 10000 khz, monitor the clk2 frequency on the circuit board at TP12 near the end of R102 with the counter, then get into Set Freq mode and adjust the reading on the frequency counter to be as close as you can get to 45005 khz above your display value or in this case 55005 khz? ?(10000 + 45005).? This is the method I used on my v6.

As mentioned by Evan, the transmit frequency in CW mode will be shifted from the displayed frequency by the tone value.? ?I modified the stock software for my own use, and in my version I changed that so the receive frequency is shifted instead.? I've not really used CW mode yet on my v6, but its on my list of things to do, so I can't vouch for how well it works in that mode.? My version is here if you have an interest.? Probably not necessary to change software if you can live with transmit shifting.



Good luck, 73
Rolan N8LOV

Thank you Evan,

After flashing N8ME version I was able to easily do the frequency and BFO calibration. With this version I don't have the problem of the calibration numbers running away.
Finally I can enjoy the radio. Thank you for the help.

73, Yvon AE7YD