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uBitX CW Sidetone Volume

Mark M
 

I find the CW sidetone on my uBitX V3 to be annoyingly loud. Any suggestions on how to quiet it down? I'm running Ian's 1.08 firmware.

Thanks...? ? ? Mark? ? AA7TA
 

The sidetone level is dependant on the level of the volume control, so as a temporary fix you could turn your volume down slightly when you start sending and then readjust it on RX.?

A permanent solution might be to try increasing the value of R253 (currently 1K). It is near Crystal X1 and the Audio connector. ?

Michael VE3WMB?
 

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Mark I replaced R250 with a 10k trimpot to set the level. R250 is located at the front of the main board at the right edge of the Raduino board.

Skip Davis, NC9O?

On Jun 20, 2018, at 20:16, Mark M <junquemaile@...> wrote:

I find the CW sidetone on my uBitX V3 to be annoyingly loud. Any suggestions on how to quiet it down? I'm running Ian's 1.08 firmware.

Thanks...? ? ? Mark? ? AA7TA

Mark M
 

Thanks, Skip, I was thinking along those lines. Did you put the pot between CW-TONE and ground and feed the wiper onward or put one end of the pot & the wiper where R250 was?

Mark? ? AA7TA
 

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I put one end of the pot and wiper where R250 was that worked for me, now mine doesn¡¯t blast my ears off with headphones.?

Skip Davis, NC9O?

On Jun 21, 2018, at 18:18, Mark M <junquemaile@...> wrote:

Thanks, Skip, I was thinking along those lines. Did you put the pot between CW-TONE and ground and feed the wiper onward or put one end of the pot & the wiper where R250 was?

Mark? ? AA7TA

Marko Pavlicevic
 

Even after replacing R253 with higher value, CW TONE is still loud.
If I remove R253, I can hear CW TONE in headphones!

Is there a way to implement CW TONE volume control in RADUINO?
 

Try a 10K or 1K preset (center and one end) parallel with C252,
this should work with 10K but if not try a 1K preset.

Raj

At 29-10-18, you wrote:

Even after replacing R253 with higher value, CW TONE is still loud.
If I remove R253, I can hear CW TONE in headphones!

Is there a way to implement CW TONE volume control in RADUINO?
 

Hi,

I installed a small pot (10k) in series with the line into the audio channel from the Raduino. The trace I broke is on the top of uBitx mother board to the right of the Raduino socket (looking at the board from the front). I cut the trace with a hobby knife, scraped the green paint off, and soldered the center and one end of the pot to those leads. The sidetone volume can then be adjusted and mine is down with the level of incoming signals. Make sure the pot (and the cut trace) is far enough to the right to clear the Raduino when it is plugged in.

73,

Bill KU8H

On 10/29/2018 05:51 AM, Marko Pavlicevic wrote:
Even after replacing R253 with higher value, CW TONE is still loud.
If I remove R253, I can hear CW TONE in headphones!

Is there a way to implement CW TONE volume control in RADUINO?



--
bark less - wag more
Marko Pavlicevic
 

Raj, I will try this.

Bill... tried that, but when keying the transmitter, I still hear the bumping of Raduino... even if the CW TONE line is grounded.
Marko Pavlicevic
 

All this when TX is off!
Marko Pavlicevic
 

Disconnected main pot and applied CW TONE direct to amplifier (R253 direct to VOL-M).
Now, CW tone can be lowered (with pot across C252) and there is no bumping sound.

So, when TX is off, and you remove R253 from the circuit, you can still somehow hear CW tone, that comes from Q70.
How is that possible?
Marko Pavlicevic
 

By TX is off, I mean TX OFF from the Raduino menu.


And, here is the picture...
Marko Pavlicevic
 

Part of the mistery solved...

If you remove R253, you can still hear CW side tone on speaker, because Arduino is using PWM pin for generating audio.
That pin behaves like an antenna, and signal from that pin enters receiver and comes to audio amplifier.

Regarding bumping sound... that sound is heard when CW key is pressed, and released (again, TX is OFF).
Tracing the problem, I found that when you cut the connection between CLK#0 pin from Raduino and main board, that sound doesn't exist any more (while pressing CW key).
Disconnecting the other two CLK signals (CLK#1 and CLK#2) doesn't make any difference.

What is so special about CLK#0 that makes bumping sound to appear?

73
Marko YU2MP
Marko Pavlicevic
 

Further research reveals that this is some audio pop error that is fixed when TX is on, but when someone wants to practice morse, there's that anoying pop again.

Reading through the forum, I found that some suggest that audio pop from TX/RX switching comes from charging mic preamp/turning off receive circuit and vice versa.
But, during TX off mode, receive circuit is always on and mic preamp is always off, but there is that audio pop again.

This time, pop comes from CLK#0 and CW_KEY Raduino pins.

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