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PTT activates menu...

Steven
 

Thanks for all the help so far. My uBitX v5, Nextion 3.2, CEC firmware radio has been a daily success. I have worked both CW and phone successfully many times. I tried to check in to a net on Sat and Sun, both times something odd happened. When I press PTT to check in ,the yellow menu comes up asking "Band Select?"  I'm not sure if my TX is getting through, and I now have to press the VFO tuner twice to return to receive status . Any suggestions?

Thanks,
Steven KM4WIP

Russ KR0EHM
 

I’m having exactly the same problem that I just noticed today but the is the first day I did some real SSB so held down the PTT.

I have the VU3SUA case but not the Nextion display. Do you have the case too? I read on another thread about the volume control being finicky with unintentional grounding because of case flex. I’m going to check that out on mine because I’ve noticed the volume control and mic cutting out on mine if I move it while it’s on.  I have a Uniden mic, the cheapo electret version from Amazon that fit the 4 pin CB XLR that came with the case.

if that’s not it then I hope for both of us my reply to bump your thread gets some attention!

here is the link to the other thread:
https://groups.io/g/BITX20/topic/59354776#72943

Biju Apkrcl
 

De VU2TDD

 This problem arises due to feedback from linier power amp. Keep away the PA and try

On Mon, 25 Nov 2019, 09:40 Russ KR0EHM, <russ@...> wrote:

I’m having exactly the same problem that I just noticed today but the is the first day I did some real SSB so held down the PTT.

I have the VU3SUA case but not the Nextion display. Do you have the case too? I read on another thread about the volume control being finicky with unintentional grounding because of case flex. I’m going to check that out on mine because I’ve noticed the volume control and mic cutting out on mine if I move it while it’s on.  I have a Uniden mic, the cheapo electret version from Amazon that fit the 4 pin CB XLR that came with the case.

if that’s not it then I hope for both of us my reply to bump your thread gets some attention!

here is the link to the other thread:
https://groups.io/g/BITX20/topic/59354776#72943

Russ KR0EHM
 

So do you mean the pots are up too high on the amp?

Russ KR0EHM
 

I found this thread with the same symptoms
https://groups.io/g/BITX20/topic/33158855#71824

Russ KR0EHM
 

Any other suggestions for KM4WIP and I on how to troubleshoot this? It sounds like there are multiple causes.

Evan Hand
 

Steven,
This is exactly what happened to me on my version 4 uBitx that I traced back to RF getting into the radio on the shield of an off center fed dipole.  Only solution was to insure good ground on the rig, snap on ferrite chokes on the outside of the coax (3 before entering the shack and one on the feed to my SWR/Power meter).  I also put smaller snapons on the digital lines to the Raduino.  Bought a kit of them on Amazon.  Be sure the largest fits the outside of your coax.

A possible test is to try the radio into a dummy load on the same frequency as you currently have the issue.  If it does not happen on the dummy load, than for sure the problem is RF feedback.

Note:  I have my uBitx rigs in metal enclosures.  If yours is all plastic, then may need to use some shielding tape on the inside of the case grounded to the braid side of the output connector.

The above is what I found, your problem may be different.

73
Evan
AC9TU

Gary Anderson
 

I am glad that Evan spoke up yet again.  Always best to invoke good RF practices.

To further the discussion: I think of this as an "Aggressor" and a "Victim."  RF is the Aggressor and the Nano controller is the potential Victim.
Solution is found when the Aggressor can not overcome the potential Victim.  Evan addresses the RF Aggressor.  What also can be done to make the Victim less susceptible?
I would try external pull-ups on PTT and F_BTN to the 5V on the Raduino board (not directly on the Nano).  Start with ~4.7K pull-ups.  This would make the pull-ups stronger and shunt some RF energy away from the Nano.
I would also disable the internal pull-up on PTT and F_BTN in the software if you have the ability to do so.
This is just a thought experiment, with no real world data, but resistors are cheap, easily available, easy to add and remove.

Rgds,
Gary
AG5TX

Evan Hand
 

I looked up the VU3SUA case.  It appears to be painted, so insure that the board and antenna grounds are solid.  This may take "star" lock washers and / or removing the paint around the the board and connector fastening locations.  Also be sure to run the shack earth ground to a point on the rig that is solidly grounded to the case.

The pull-up resistors are a good idea as well, though did not need them in my case.

Again, just my thoughts.
73
Evan
AC9TU