Enabling VOX causes bad RX

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N6WLM
 

Posts: 20
Joined: 12 Jul 2022, 03:15

Enabling VOX causes bad RX

Post by N6WLM »

Hi all,

I have an odd issue. Enabling VOX will cause my receive to be full of noise. I've tried setting the noise gate and TX delay with no luck. I also re-flowed the soldier from MIC path to the ATmega in hopes that would help. Are there any other things I could try to debug the issue? I was hopping to try digital modes using my phone via VOX.

Here is an audio clip of enabling and disabling VOX. The noise disappears when VOX is disabled.

Thank you,
Bill N6WLM
Last edited by N6WLM on 06 Sep 2022, 17:11, edited 1 time in total.
Ohwenzelph
 

Posts: 207
Joined: 01 Jan 2022, 03:47

Re: Enabling VOX causes bad RX

Post by Ohwenzelph »

I had two from one group buy. On one the vox seems to work ok, but on the other, if I turn the vox on, the resting power use doubles and it kinda locks up, the button response and screen mostly stop responding, it pretty much crashes and have to cycle the power. I reloaded the firm ware and it seemed to fix it but I have not really used vox on it any.
N6WLM
 

Posts: 20
Joined: 12 Jul 2022, 03:15

Re: Enabling VOX causes bad RX

Post by N6WLM »

I tried new and old firmware but still have the issue. Pulling the on-board mic from the main board made no difference either.
John
 

Posts: 49
Joined: 19 Feb 2022, 08:56

Re: Enabling VOX causes bad RX

Post by John »

You haven't mentioned if the rig works properly on CW, or on SSB, or AM, or FM each with or without VOX enabled, i.e. other modes that use the Mic inputs to the processor. That would tell us more about the specific nature of the problem.

Either way, my guess is that it's a problem with the microcontroller chip.
N6WLM
 

Posts: 20
Joined: 12 Jul 2022, 03:15

Re: Enabling VOX causes bad RX

Post by N6WLM »

John wrote: 07 Sep 2022, 00:09 You haven't mentioned if the rig works properly on CW, or on SSB, or AM, or FM each with or without VOX enabled, i.e. other modes that use the Mic inputs to the processor. That would tell us more about the specific nature of the problem.

Either way, my guess is that it's a problem with the microcontroller chip.
The TX sounds okay for CW, USB, and LSB. I have to yell into the MIC to get AM or FM to TX. VOX will only trigger for USB and LSB.

RX sounds great on all modes except FM. With VOX enabled LSB and USB are unusable. The noise is present even without the RF board plugged in and VOX enabled.
pe1nnz
 

Posts: 50
Joined: 30 Dec 2021, 19:29

Re: Enabling VOX causes bad RX

Post by pe1nnz »

Hi Bill,

I am unable to reproduce this on the latest beta version, but we had such an effect in an older version.

Could you please confirm you are using a version older than R2.00c?
You can find the version number in the menu or is visible on startup.

In addition. can you confirm that ATT is set to 0dB?

Are things improving when increasing the Noise Gate level?

73, Guido
KD9SPR
 

Posts: 2
Joined: 07 Sep 2022, 02:30

Re: Enabling VOX causes bad RX

Post by KD9SPR »

I also saw this vox problem trying to get FT8 working last weekend. I was able to Tx FT8 and confirm on pskreporter manually pressing PTT at appropriate times.

When I enabled vox on trusdx it seemed to work for a minute or two, then display stopped showing frequency and buttons stop working. I am on the 2.00i release.
pe1nnz
 

Posts: 50
Joined: 30 Dec 2021, 19:29

Re: Enabling VOX causes bad RX

Post by pe1nnz »

Could it be that the Windows audio mixer settings are such that it passes the receiver audio to the sound card speaker output?

and then activating the VOX with this receiver noise?

Note that in VOX TX mode buttons presses are not effective.
N6WLM
 

Posts: 20
Joined: 12 Jul 2022, 03:15

Re: Enabling VOX causes bad RX

Post by N6WLM »

pe1nnz wrote: 07 Sep 2022, 11:46 Hi Bill,

I am unable to reproduce this on the latest beta version, but we had such an effect in an older version.

Could you please confirm you are using a version older than R2.00c?
You can find the version number in the menu or is visible on startup.

In addition. can you confirm that ATT is set to 0dB?

Are things improving when increasing the Noise Gate level?

73, Guido
Hi Guido, thank you for helping.

I have the issue when testing with R2.00i and R2.00l (beta). I set ATT to 0dB and ATT2 to 0. A Noise Gate under 2 will TX continuously without external MIC audio. VOX will TX as it should with a noise gate of 3 or more but still has RX noise all the way up to a the max value of 255. At one point I removed the on-board MIC and had no external connections to the main board but still had RX noise with VOX enabled.

I feel like I might be picking up MIC noise in the circuitry heading into the Atmega. I don't see any shorts on the board though.
pe1nnz
 

Posts: 50
Joined: 30 Dec 2021, 19:29

Re: Enabling VOX causes bad RX

Post by pe1nnz »

Ok tnx Bill I have no idea but will dive into this to see what can cause this.
KD9SPR
 

Posts: 2
Joined: 07 Sep 2022, 02:30

Re: Enabling VOX causes bad RX

Post by KD9SPR »

pe1nnz wrote: 07 Sep 2022, 21:12 Could it be that the Windows audio mixer settings are such that it passes the receiver audio to the sound card speaker output?

and then activating the VOX with this receiver noise?

Note that in VOX TX mode buttons presses are not effective.
Quite possible audio mixer issues, but that would just cause T to show for transmit unexpectedly? The problem I observed had no frequency on display and buttons not responding.

I tried on a different PC last night for 15min or so and did not have the display/button problems, the vox T indicator showed at expected times when FT8 Tx. I have not changed the default settings for : ATT=0dB, ATT2=2, NoiseGate=4

While FT8 was Rx( &vox enabled), I was able to PTT and see the T indication on display.

Thank you for all your work on this project, PE1NNZ!
N6WLM
 

Posts: 20
Joined: 12 Jul 2022, 03:15

Re: Enabling VOX causes bad RX

Post by N6WLM »

pe1nnz wrote: 08 Sep 2022, 10:54 Ok tnx Bill I have no idea but will dive into this to see what can cause this.
Thank you for looking into it! I have been getting bad signal reports lately as well. Ive been told my voice sounds like there is RF on the line. Are there are any known voltages I can check for in the audio path so that we can exclude a hardware issue?

I have a Lo and Hi band RF board now. Both have VOX issues and poor TX voice quality. My main board has an LT6231 OpAmp so it is probably not the LMH6622 issue.
we1h
 

Posts: 1
Joined: 30 Jan 2023, 16:43

Re: Enabling VOX causes bad RX

Post by we1h »

At the risk of acivating relativly old thread, I wanted to provide a bit of info on what I am experiencing of this issue on my new to me unit. FW: 2.00i ...

With the rig connected to a PC sound with volume at +10
Mode: USB
Noise Gate:4 - 2 Outcome: VOX works as expected
Noise Gate:1 or 0 Outcome: VOX no longer works and rig goes into TX unexpectedly

With the rig NOT connected to a PC sound with volume set to +10 or 0
Mode: USB
Noise Gate:4 - 2 Outcome: VOX works as expected
Noise Gate:1 - 0 Outcome: VOX no longer works and rig goes into TX unexpectedly

Perhaps related or not, if i switch the rig to CW mode, VOX on or off, with no key attached, the rig immediately goes into TX mode, regardless of Noise Gate setting. Plugging in a cable to the Mic/Key port stops the behavior from occurring.

Thanks for such a cool and fun rig! I've got a bunch of QRP rigs, but this one is becoming my facorite quickly.

73,
Matt, WE1H
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