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Keyer hanging when using SOTAbeams dipole


Richard
 

Just upgraded tonal the latest firmware via chip replacement and my QCX hangs with the letter G at the end of th4 frequency displayed on the top line.  Works fine with a dummy load.  The SB antenna works fine on my FT891 and FT818.  I think it has worked on the QCX also.  Any ideas? 


N3MNT
 

Do you have anything connected to the GPS port?.  The G thinks the QCX is receiving GPS Data.


Richard
 

Nope.  Nothing.  


Ronald Taylor
 

Richard, first make sure you don't have any solder shorts in the area of JP1. Then, since you indicated that you did the firmware via chip replacement, you might want to take another look at the pins and make sure all 28 of them went into the socket properly. If that doesn't do it. I would suggest a factory reset. 

Ron

On Sun, Sep 20, 2020 at 2:51 PM Richard <groups.io@...> wrote:
Nope.  Nothing.  


Ham Radio
 

If Ron’s suggestion does not work, try running the QCX on battery power.  

Perhaps you are picking up some stray RF somewhere causing the QCX micro-controller to hang.
--
73, Bernie, VE3FWF
(most typos in this message have been generated by highly sophisticated auto-correction software)


Richard
 

Crap, I meant to try  a factory reset while at the park.

I was testing it out in the configuration I plan on using for SOTA.  It was running on a 1500mAh LiPo. 

Will try it with my balcony WRC tonight.  


Richard
 

Hangs using the WRC as well.

Something that I did notice that is very odd.

If I hold the unit in the air, it works perfectly.  If I set it down on a surface, it may work for a while but will eventually hang.  There is also a distinctive buzz in the sidetone when the device is sitting on a surface that is NOT there when I am holding it in the air.  I've tried rotating it around all three axis when in the air with no change.  When I put it down, though, the sidetone gets a buzzing noise and the "G" starts coming on and causing sending to hang.

I need to find the old chip with the previous version firmware and give it a try.  Could my board revision not be compatible with the 1.05 software?


Ronald Taylor
 

Richard, all the firmware revisions are backward compatible with all board versions. Older boards won’t have the components to support the CAT interface that’s in the newer firmware versions but that won’t affect the rest of the operation of the board. But it’s a good idea to go ahead and try the earlier version chip and see what happens. 

It really sounds like you have some stray RF issues. If holding it up in the air fixes it, try just touching it while it’s on the bench and see if that fixes it too. 
Did you have the same problems with it at the park today?  

Ron

On Sun, Sep 20, 2020 at 19:33 Richard <groups.io@...> wrote:
Hangs using the WRC as well.

Something that I did notice that is very odd.

If I hold the unit in the air, it works perfectly.  If I set it down on a surface, it may work for a while but will eventually hang.  There is also a distinctive buzz in the sidetone when the device is sitting on a surface that is NOT there when I am holding it in the air.  I've tried rotating it around all three axis when in the air with no change.  When I put it down, though, the sidetone gets a buzzing noise and the "G" starts coming on and causing sending to hang.

I need to find the old chip with the previous version firmware and give it a try.  Could my board revision not be compatible with the 1.05 software?










Richard
 

Yes, that's where I first noticed it.

I took it on a SOTA activation a few weeks ago and had no issues.  Used the same setup except I had an EFHW instead of a dipole or loaded coil.

I tried my Bencher BT-2 and had absolutely NO difficulties whatsoever.  No keying issues, no hum, and great RBN spots.  I tried the N0SA paddle and had the same hum and hanging.  I tried a SW Morse pico straight key and while I had a hum, the keyer never hung.  Neither did the built-in keyer.  Of course, I had the box set for straight key so there would be no internal dits and dahs being generated.

I did also notice that my RBN signal strength was significantly lower when calling CW with the hum than without.

Touching the case is the magic!  Everything works perfectly.  Guess I'll have to bond myself to the case with an anti-static strap!  LOL

Now I just have to remember where I put that old chip.  :( 


Hans Summers
 

Hi Richard

Finding the old firmware chip will work, because the old firmware did not have the GPS auto-detect that automatically protected the transceiver when you plugged in a GPS, and displays "G" on the screen to indicate that it has done so. 

But the old firmware just hides your problem, not fixes it. Everything you have said points to a big problem with your antenna set up. You had better fix this real problem, not just symptoms. For some reason, that antenna isn't working correctly... and you have lots of RF around your radio, earthing system, etc. 

73 Hans G0UPL
http://qrp-labs.com

On Mon, Sep 21, 2020 at 6:15 AM Richard <groups.io@...> wrote:
Yes, that's where I first noticed it.

I took it on a SOTA activation a few weeks ago and had no issues.  Used the same setup except I had an EFHW instead of a dipole or loaded coil.

I tried my Bencher BT-2 and had absolutely NO difficulties whatsoever.  No keying issues, no hum, and great RBN spots.  I tried the N0SA paddle and had the same hum and hanging.  I tried a SW Morse pico straight key and while I had a hum, the keyer never hung.  Neither did the built-in keyer.  Of course, I had the box set for straight key so there would be no internal dits and dahs being generated.

I did also notice that my RBN signal strength was significantly lower when calling CW with the hum than without.

Touching the case is the magic!  Everything works perfectly.  Guess I'll have to bond myself to the case with an anti-static strap!  LOL

Now I just have to remember where I put that old chip.  :( 


Richard
 

I've tried with multiple antennas and they are all having the same issue.  They are not complex antenna setups and I have been using them in the field for over a year with an FT818 and FT891 with no apparent issues.

SOTAbeams 20/30/40 linked dipole
WRC SB1000

I haven't tried with the QRPGuys EFHW but I suspect it will have the same issue.  I find it hard to believe that multiple antennas, which show SWR <1.5 and no apparent issues on a NanoVNA are both having these problems.  The SOTAbeams is basically two wires and a toroid into RG174 feedline.  You can't get much simpler than that.  :)

Any suggestions on where to start hunting this down?


Richard
 

One more thing.  Do you have any ideas on why the Bencher BY-2 key works flawlessly buy my other two keys seem to cause the issue?  Exact same setup, radio sitting in the same place.  That's really strange.  Could the cables, or the key itself, be picking up RF and feeding it back into the circuit?  I know the GPS and keyer share a common IO port (or something like that).


Evan Hand
 

Richard,
As a guess and only a guess, I would look to grounding as a potential issue.  It could be that in the shack there is interference that is not present in the field.  The fact that when you touch the rig it reduces the failures also points to a grounding issue.

I would start there and maybe look into bypassing the keyer/GPS input with a cap that is low enough to not cause issues with the GPS and keyer signal, yet high enough to short any RF.

Again, this is a guess.
73
Evan
AC9TU


geoff M0ORE
 

Tried on a dummy load?

What is the distance between the transmitter and the balun?

On 21/09/2020 13:46, Richard wrote:
I've tried with multiple antennas and they are all having the same issue.  They are not complex antenna setups and I have been using them in the field for over a year with an FT818 and FT891 with no apparent issues.

SOTAbeams 20/30/40 linked dipole
WRC SB1000

I haven't tried with the QRPGuys EFHW but I suspect it will have the same issue.  I find it hard to believe that multiple antennas, which show SWR <1.5 and no apparent issues on a NanoVNA are both having these problems.  The SOTAbeams is basically two wires and a toroid into RG174 feedline.  You can't get much simpler than that.  :)

Any suggestions on where to start hunting this down?


Richard
 

Well, I think it's resolved. 

Since it only happened with the mini key I use in the field I decided to look at that.  I then remembered I had tightened it up a little bit.  I backed off on the DAH contact just a tad and the issue went away.  I wonder if the two contacts were close enough to, for some reason, pick up RF from the BNC jack and feed it back into the keyer port?

REALLY strange. 


Jim Painter
 

It sounds like your coax is radiating. Check the coax/connectors. Check the bnc connections in the radio.

Jim...kq3s 


On Sep 21, 2020, at 8:46 AM, Richard <groups.io@...> wrote:

I've tried with multiple antennas and they are all having the same issue.  They are not complex antenna setups and I have been using them in the field for over a year with an FT818 and FT891 with no apparent issues.

SOTAbeams 20/30/40 linked dipole
WRC SB1000

I haven't tried with the QRPGuys EFHW but I suspect it will have the same issue.  I find it hard to believe that multiple antennas, which show SWR <1.5 and no apparent issues on a NanoVNA are both having these problems.  The SOTAbeams is basically two wires and a toroid into RG174 feedline.  You can't get much simpler than that.  :)

Any suggestions on where to start hunting this down?


Richard
 

Well, I just tried it again.  Same issue.   Apparently it wasn't an issue with the key.

I tried connecting it to a power supply instead of battery and it works fine with it.  Seems like the power supply is giving it a ground.

BNC connection looks good.  The mystery is why it works with the Bencher and not the Mini-paddle I use for SOTA/POTA?


Peter GM0EUL
 

My guess is that it might be a bad capacitor (dry joint or failed component) between the key line and ground.  I don't have the schematic handy so can't suggest which to look at.  Anything that replaces the capacitance might appear to fix it hence touching it etc.  My theory would explain the Bencher phenomenon by suggesting it's big steel body and arms introduce enough capacitance to ground to get rid of the stay RF. Same with the PSU.  

My second guess it that it might not be that.

73
Peter
GM0EUL


Trystan G0KAY
 

I'd perhaps look at the lengths of the cable from the two different paddles, and the cable itself. If the Bencher BY-1 is behaving itself, then see if you can use the same lead and lead length for the other paddle too. You could also put 10nF caps across the paddle keys and a ferrite on the paddle lead too. 


Richard
 

Based on the schematic, the ground of the keyer paddle connected directly with no components in between.  I was thinking the same thing on the Bencher since it is massive compared to the SOTA key. 

The cables are pretty much the same length.  I may try making a female to male 1/8" extension with a cap across the key lines.  I did try a huge choke on the paddle line with no luck but it was made for a power supply cord and may have been too big.  Plan on trying a more appropriate one later today after replacing the XYL2b's air conditioner condenser fan motor.