Audio "click" during knob rotation


Yury Krasouski
 

Hi HAMs,

Could you do I favor and answer following question about QCX mini.

Each time I rotate VFO knob I hear in headphones quite strong audio “click” even with antenna connected.

This is not mechanical “click” and it appears during frequency change, menu change. Also “click” present when I rotate knob with LCD module disconnect.

I cannot understand is this common problem or only of my QCX mini.

If problem with my item probably someone give an idea how to troubleshoot this.


Jack G5JDA
 

I also have this on QCX mini (but not QCX+), although for me it is very weak and not audible when there is noise from antenna unless volume is turned all the way down. I had a theory that it was interference from the LCD module / control lines but since it doesn't bother me in actual use I didn't investigate it yet.


Jim Ladd
 

I think I remember running into this when I was using a very weak battery to power the QCX (original, not mini).

Jim / KF0RST


 

There was a lot of discussion on this issue barely a month ago... The general (though not universal) understanding is that it was microphonic part(s) - probably capacitors - in the vicinity of the handwheel encoder, inducing an electrical signal into the signal path.
--
Julian, N4JO.


Yury Krasouski
 

Many thanks.

Here is I recorded video with my QCX mini clicks.

Without antenna clicks very noticeable during frequency or menu item change.

With connected antenna clicks can be recognized (probably video cannot provide this).

https://youtu.be/zN7kW1bXjIg

I asked a few peoples about this behavior. QCX plus users reported that don't have such clicks at all.

Probably this is QCX mini specific problem.

The my main question is this common behavior or problem with my QCX mini?


Yury Krasouski
 

Also have to mention that increasing volume increasing gain of click.


Gary Bernard
 

I have an almost inaudible click and volume has no relation to the click.
Gary W0CKI


-----Original Message-----
From: Yury Krasouski <krasoffski@...>
To: QRPLabs@groups.io
Sent: Fri, Jun 18, 2021 3:33 pm
Subject: Re: [QRPLabs] Audio "click" during knob rotation

Also have to mention that increasing volume increasing gain of click.


Yury Krasouski
 

Can be the main reason of thin dc regulator used for RF analogue and digital parts at the same time?


Michael Bendio
 

I’m bothered by the same click in my QCX mini. My understanding is that it comes from the frequency synthesizer. But it does lessen my enjoyment of the radio.


Yury Krasouski
 

Michael, I also thought in the same way. But you can notice in my video that my QCX mini has clicks during menu items walk without frequency frequency change.


KEN G4APB
 

Hi Yury,
my QCX-mini has a loud ‘crack’ sound when I change frequency using the startup 10khz step, but is just a click on the smaller frequency steps. I am not sure of the reasoning, but the 10khz step is only available immediately after power-on, once I move to the smaller steps, I cannot go back to a 10khz step, so I don’t really experience the crack sound as a nuisance.
73 Ken g4apb 


Yury Krasouski
 

Thank you,Ken

Yes, mine QCX mini also has 'crack' with big steps. BTW, you can change steps to 'big' ones by presing encoder button and rotation at the same time.


Hans Summers
 

Hi Ken

As Yuri says, you can change the step beyond the usual 1kHz-500Hz-100Hz-10Hz cycle by pressing-and-turning the rotary encoder... when you turn the rotary encoder and the button is held in, it moves the step underscore left and right. 

The 10kHz you see must be selected as the power-up frequency step in your VFO configuring menu. 

The loud click is due to a PLL RESET command which is issued to the Si5351A when tuning in steps 10kHz or bigger. Years ago when I wrote that piece of code there was some doubt about when PLL reset is required, as the datasheet and AN619 are not informative on this point; the idea that a reset might be needed for large frequency changes is inherited from the way the Si570 works. However I now know that the way the QCX uses the Si5351A this reset is not required. In the next firmware release I will remove that >= 10kHz step RESET. It hasn't bothered most people since most people don't feel the need to tune in 10kHz steps. 

Whenever there is a tuning step even small sizes, there will always be a small "whoosh" kind of sound as I call it, due to the sudden frequency change; this is not normally heard when you have an antenna connected. On QCX-mini there is also the possibility of low level microphony due to the SMD capacitors; this was substantially (and sufficiently) reduced by using through-hole capacitors in critical places and this is documented in this article: http://qrp-labs.com/qcxmini/qcxminidev4.html

73 Hans G0UPL 

On Sun, Jun 20, 2021, 10:10 Yury Krasouski <krasoffski@...> wrote:

Thank you,Ken

Yes, mine QCX mini also has 'crack' with big steps. BTW, you can change steps to 'big' ones by presing encoder button and rotation at the same time.


Mont Pierce KM6WT
 

On Sun, Jun 20, 2021 at 03:42 AM, Hans Summers wrote:
As Yuri says, you can change the step beyond the usual 1kHz-500Hz-100Hz-10Hz cycle by pressing-and-turning the rotary encoder... when you turn the rotary encoder and the button is held in, it moves the step underscore left and right. 
This is a little confusing, but works.

The thing is, when I first press-and-hold the rotary button, the display shows the Messages memories.  I need to release the rotary button, and press-and-hold a second time. Then turn the rotary dial to move the underscore left and right.

Not sure if this is a bug, as it does not work "exactly" as Hans' described.  But if it is a bug, it's very minor, as it always works on the 2nd press-and-hold.


73
km6wt




Hans Summers
 

Hi Mont
As Yuri says, you can change the step beyond the usual 1kHz-500Hz-100Hz-10Hz cycle by pressing-and-turning the rotary encoder... when you turn the rotary encoder and the button is held in, it moves the step underscore left and right. 
This is a little confusing, but works.

The thing is, when I first press-and-hold the rotary button, the display shows the Messages memories.  I need to release the rotary button, and press-and-hold a second time. Then turn the rotary dial to move the underscore left and right.

Not sure if this is a bug, as it does not work "exactly" as Hans' described.  But if it is a bug, it's very minor, as it always works on the 2nd press-and-hold.

It's not a bug, it works correctly, it's more an "inevitability"; the button is loaded with several different functions depending on whether tapped once, twice, or one long press. On the left button there is also triple-tap to toggle the LCD backlight (applicable to QCX-mini only); on the right button there are more functions too (like taping a CW 'N' to set VFO A = B, or a CW 'D' to set VFO B = A); and on the encoder shaft you have press-and-turn to move the tuning step cursor. 

All of this is a consequence of having buttons do multiple things; one tries to design the user interface so that things that are needed most often are the most intuitive and easy to reach. But there are clearly always going to be some compromises. On the other hand if you were to have one button/knob for every function of the radio then you have a MUCH bigger and more expensive radio. 

In the specific case of push-and-turn the rotary encoder shaft; the system has to decide what are your intentions. There is a 0.3 second delay built in. If you press the button 1, 2 or 3 times within that 0.3 seconds delay then it is interpreted as such. If you are still pressing the button after 0.3 seconds then it decides you intended to do a "long press". If you want to push-and-turn to move the tuning step cursor, you have to initiate the turning in less than 0.3 seconds after pressing. Otherwise it will be interpreted as a long-press, not a press-and-turn. 

Note that the 0.3 seconds is also adjustable in the Other menu. 

So it IS possible to correctly use the rotary encoder shaft to press-and-turn to move the tuning step cursor left and right; However you do have to be quick. 

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


Mont Pierce KM6WT
 

On Sun, Jun 20, 2021 at 07:36 AM, Hans Summers wrote:
If you want to push-and-turn to move the tuning step cursor, you have to initiate the turning in less than 0.3 seconds after pressing. Otherwise it will be interpreted as a long-press, not a press-and-turn. 
 
Note that the 0.3 seconds is also adjustable in the Other menu. 
 
So it IS possible to correctly use the rotary encoder shaft to press-and-turn to move the tuning step cursor left and right; However you do have to be quick. 

Ah, that explains it.  I'm just doing it wrong (as usual).

However, I am glad that the "second" press-and-hold does always work, even with my old fingers and fading quickness...


Thanks Hans.   I should have known better...



73
km6wt


KEN G4APB
 

Well thanks guys for the info,
I must admit I tried this several times and keep getting the tx sending a message. However, I did have the QLG2 connected and beacon mode set in the menu. I was backing out of beacon mode to set mat receive frequency, then going to Preset to get beacon back on. I tried pulling out all the GPS/paddle connections and set wspr beacon mode to OFF, THEN, the freq step to worked as you describe! I have learnt something new.
Thanks for the explanation for the louder click at a 10khz setting Hans, all makes sense now.

BTW, a secret hidden function in beacon mode is that while awaiting wspr beacon transmission, the qcx-mini is actually receiving on the chosen VFO frequency plus the offset (nominally +700Hz), so for wspr transceiver operation, I set VFO A to 7.040,10 (hence the clicks heard), and 3.8 CW offset to 1500hz, bypass the cw filter (add switch) and then set wspr beacon mode operating.
73 Ken g4apb 


Yury Krasouski
 

Here are small updates from investigation audio clicks.

I connected EM14 (EM14R0D-R20-L032S) optical encoder and this did not change anything with clicks. Clicks still present and much louder that background noise with connected LW antenna on 40m.

The good news is that optical encoder works like a charm with QCX mini. Thus, if you have custom enclosure for your QCX it is worth to install it to have VFO knob like in expensive rigs =)

Also I noticed following, if very slowly turning the optical encoder I hear clicks without any change in frequency or menu items change. This looks like I have clicks for each encoder "clock".

Probably I have to check oapms input/output for spikes during turning using my pocket oscilloscope but my ideas run out =)

Here is video with optical encode: https://youtu.be/lM7Ooi_2MVU


Yury Krasouski
 

Also noticed today that with fast turning of VFO and enabled S meter it shows about half of bar on dummy load.


jerry@tr2.com
 

One thing I've noticed - with my Bourns encoder that I installed in the QCX+ - is that if I spin the dial fast, it often tunes *backwards*.

- Jerry KF6VB

On 2021-06-21 15:20, Yury Krasouski wrote:
Also noticed today that with fast turning of VFO and enabled S meter
it shows about half of bar on dummy load.
Links:
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[1] https://groups.io/g/QRPLabs/message/67568
[2] https://groups.io/mt/83622776/243852
[3] https://groups.io/g/QRPLabs/post
[4] https://groups.io/g/QRPLabs/editsub/243852
[5] https://groups.io/g/QRPLabs/leave/10312280/243852/1190336630/xyzzy