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uBitz 3 / 6 Easy way to key carrier for tuner adjustment?


kg9hfrank@gmail.com
 

Curious is there an easy way to access a point to transmit a small carrier (50%?) to adjust your tuner?
--
Frank, KG9H


Evan Hand
 

I use a "tune" function on the WSJT-X software to send a lower power audio signal to the transceiver.  Since SSB output is dependent on the audio level supplied.  Setting up a single tone audio signal that is much lower than normal on SSB would be the same (almost) as a low power CW signal.  

the other options that I have seen (but not tried) is to add a relay (or switch) and another RV1 pot to change the output level.

Either should work, so depends on where you want to make mods.

73
Evan
AC9TU


Curt
 

How about a morse key? With stock firmware, just press the key. With other, just change the mode to cw. Just like other rigs. If you must have 50 percent audio, you need to build a oscillator.

73 curt


Jonas Sanamon
 

This is how I do it,  I have added a pushbutton on the front that is connected to the CW key jack.  You don't have to switch mode to CW to use it, just make sure CW key mode is set to straight key before U start using it.  It works fine also in SSB mode.  It will be "full power" though, but as full power isn't more than 10-15w i just use it this way.

Regards, Jonas


Den tors 26 nov. 2020 kl 17:52 skrev Curt via groups.io <wb8yyy=yahoo.com@groups.io>:

How about a morse key? With stock firmware, just press the key. With other, just change the mode to cw. Just like other rigs. If you must have 50 percent audio, you need to build a oscillator.

73 curt


Bob Lunsford
 

If you have a mic with a locking PPT switch AND it has the right connector, merely push/lock the mic PTT switch and it does the same thing. Like Microsoft Windows, there's always a workaround.

Bob — KK5R

On Thursday, November 26, 2020, 12:24:24 PM EST, Jonas Sanamon <sanamon@...> wrote:


This is how I do it,  I have added a pushbutton on the front that is connected to the CW key jack.  You don't have to switch mode to CW to use it, just make sure CW key mode is set to straight key before U start using it.  It works fine also in SSB mode.  It will be "full power" though, but as full power isn't more than 10-15w i just use it this way.

Regards, Jonas


Den tors 26 nov. 2020 kl 17:52 skrev Curt via groups.io <wb8yyy=yahoo.com@groups.io>:
How about a morse key? With stock firmware, just press the key. With other, just change the mode to cw. Just like other rigs. If you must have 50 percent audio, you need to build a oscillator.

73 curt


IW4AJR Loris <lorisbollina@...>
 

Hello Frank:

A simple schematic to add inside the µBITX (see the attached files) ...
 
Use:
1) Connect the circuit as shown in the figure to the µBITX, the power supply takes it from the Mike power supply and consumes no more than 3-4 mA.
Mode TX in SSB.
2) Connect the µBITX to a dummy load.
3) Activate transmission with switch S1.
4) Adjust the BF level with the R9 trimmer for the desired output.
5) Put the µBITX in reception, always with S1,
6) Connect the ATU and act on S1 for the TUNE.
 
The frequency is about 1,300 / 1,400 Hz, approximately in the middle of the BF band.
 
The two graphs are derived from the simulation with LTspice and detect a discrete spectral content.

The circuit is so simple that you can make it even on a small prototype board.
 
A cordial greeting ... 73 de Loris IW4AJR


kg9hfrank@gmail.com
 

Thanks all.  I have the information that I need now.  Will be on MIDCARS 7.258 today with my v6 while I work on my v3.  Hope to work some contacts there.

--
Frank, KG9H


Mark Erbaugh
 

If you don't mind mucking with the firmware, I found that by raising the TX_RX and CW_KEY outputs of the Arduino and setting the Si5351 clocks appropriately, the uBITX (version 6) can generate a CW carrier. This is the same way the radio generates CW except that the carrier is continuous. Wanting to protect the finals, I modified the firmware to modulate the carrier by pulsing the CW_KEY signal to effectively reduce the average power. My firmware has an 8 msec heartbeat interrupt so I turn CW_KEY on for 8 msec then off for 24 msec to get a 25% duty cycle. Since this is hard on/off keying, I doubt the signal is very clean, but it works for tuning purposes.

73,
Mark, N8ME


IW4AJR Loris <lorisbollina@...>
 

Hello Mark,

Your idea is very good, but if you want to use the original software or use the available RAM space of the original raduino (µBITX-V6) for other modifications, for example the display of the S meter available in the kit-project AGC via the ADC A7 available, the use very low level single tone SSB modulation, may be better.
 
Ciao from IW4AJR Loris


IW4AJR Loris <lorisbollina@...>
 

P.S.

Another way is to modulate the SSB with a "dual tone generator", if you have a Modulator Display, to check the cross modulation and fix the BF level around 90% of the maximum power, this will produce an "Average Power" output from the power amp equal to about 50% of the CW power, it would be the best way, but the circuit is a bit more complex and a novice may have difficulty building it, plus not everyone has a tool to view the modulation in output available in the shack ...
Hello everyone Loris IW4AJR


Bob Lunsford
 

Sounds like a good use for an old CPO... Just feed speaker output into the microphone. Simple.

Bob — KK5R

On Monday, November 30, 2020, 4:00:08 AM EST, IW4AJR Loris <lorisbollina@...> wrote:


Hello Mark,

Your idea is very good, but if you want to use the original software or use the available RAM space of the original raduino (µBITX-V6) for other modifications, for example the display of the S meter available in the kit-project AGC via the ADC A7 available, the use very low level single tone SSB modulation, may be better.
 
Ciao from IW4AJR Loris