Ubitx v6 No Output on SSB #ubitx-v6 #ubitxv6 #wsjt-x #ubitx-help


Spencer Nelson
 

Ubitx v6, only mod being a nextion display and kd8cec software

-I have output on cw mode, 8ish w on 80m varying through the bands
-the stock mic keys the radio as a cw key in the key jack and puts the radio into transmit when in the mic jack.  no output from the radio in ssb when speaking into the mic. 
-I have tried to operate the radio in ft8 as well with a signal link and a computer.  I can key the radio, but no output. 
-I have verified good connection at the mic jack on the board, tested the wires on the mic from the jack to the circuit board inside the mic. 
-I tried a c/b mic with a built in amplifier (using an adapter) that has a built-in amplifier and battery. no change.
-a quick look at the circuit board doesn't reveal any defects, or bad solders.

I originally thought it was the mic but if that was the case, it should have worked when using ft8 with the signal link. 
I am intending to use this radio for portable operation both digital and ssb, so having the mic/ssb working is crucial.  Not sure if I have a mic/audio issue or something else at this point.....

Thanks in advance for advice/next steps to test.


Evan Hand
 

Hi Spencer,

Does the v6 receive as expected?  The most likely issue is that it is not calibrated correctly.  This is most likely the case if you changed the Nano when you installed the KD8CEC software.  The calibration data is stored in the EEPROM that, is not updated when you download the program, and stays with the Nano.

The next most likely issue would be the mic preamp, Q6.  You can use the v4 voltage spreadsheet to check the transistors of proper dc bias voltages provided by VU2ZAP:
https://groups.io/g/BITX20/files/VU2ZAP

73
Evan
AC9TU


Spencer Nelson
 

Hi Evan,

It does receive but it is off the frequency is slightly off.  I'll try a calibration since I did change the nano when I changed software.
If that doesn't get me anywhere I'll look at those voltages.  

Thanks, 73
Spencer VA3SPN


Spencer Nelson
 

I tested the voltages at q7 and they are very similar to the readings on the chart you provided the link to.  I did some more testing, this time with a Bird 43 meter with peak kit.  Turns out that it does transmit when in ssb mode, my other meter doesn't read peak even though it has a peak switch on the front.....
The radio was still a bit off, so I took a shot at calibrating the unit.  Following the instructions on the ubitx site I tried tuning it to a strong am station and calibrating the vfo. (the station os 820khz).  After trying the best I could to zero beat the station, I tuned to 7.074 to see if I was on frequency as a test. I'm not sure how, but this thing has still managed to stay tuned to the am station. I have tried to power cycle it, unplugged power, even reinstalled the old display and arduino.
I'm not even sure where to go with this thing now, nothing it is doing is making any sense. 

Thanks
Spencer VA3SPN


Evan Hand
 

Hi Spencer,

If I have read your post correctly, you can not change the frequency with either of the two Nano MPCs.  I do not see how that can happen unless you plugged the tuning encoder into the mainboard instead of the Raduino board.  Have you tried to set the frequency with the touch display?

73
Evan
AC9TU


Spencer Nelson
 

Hi Evan
The encoder is plugged into the back of the raduino board. I can change the frequency in the screen, and I am able to pick up strong signals while tuning (ie: 40m Ft8) but even while I hear the Ft8 tones the am station is still coming through as well. 

if I have time in the next few days I’ll try and record a video of what it’s doing. This thing is weird. 

73
Spencer
VA3SPN


Evan Hand
 

Spencer,

There are two possibilities that I can think of:
1 - The AM station is close to your QTH and overloading the first mixer.  That would mean a BCI filter is needed.
2 - The other possibility is that you tuned the v6 to receive the BC signal and not the standard HF band signals when you did the calibration.  That would require a recalibration using another standard.  I use WWV, though dealing with the tones is an issue.  The other calibration option would be to use a signal generator as the AM source.  By chance, do you have a NanoVNA or TinySA?  Either can be used as a signal generator if you do not have one.

The most likely cause is the first.
By chance, did you save the calibration file using the Memory Manager from KD8CEC?  If so, I would load that into the Nano with the KD8CEC software and see if that solves the problem.

73
Evan
AC9TU


Spencer Nelson
 

Evan

I didn’t save a copy of the calibration unfortunately. I didn’t know that was possible. I’ll look into the memory manager. 

The am station was not coming through before I tried tuning to it. I’ll have to try another calibration. I do have a nano vna so I’ll give that a shot. 

73
Spencer
VA3SPN