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TUNE signal for tuning tuners


Frank Krozel
 

Thanks everyone, lots to think of, I use a paddle when remote operation so looking for something simple.  Lots to digest, thanks all. Frank KG9H
(Informal uBitz net Sunday, 7.277 9:30A Central.  de KG9H


Al Duncan VE3RRD
 

Another option for adjustment of a tuner without transmitting is ND6T's "Polite Antenna Tuner" at http://www.nd6t.com/antenna/Polite%20Tuner.htm


Vince Vielhaber
 

When you close the key, 5V is applied to unbalance the ring. A pot with a switch can take the place of that. Wiper of the pot thru the switch then to TP13 thru a diode and probably a 2k resistor. One side of the pot to ground, the other to 5V. Put the uB in CW and turn the pot to the desired output. I know it works, I did it on my Bitx 40.

Vince.

On 01/20/2021 04:12 AM, Evan Hand wrote:
Vince,
I have not tried to use a variable voltage on the mixer diodes to
control power through the unbalanced ring. Not sure if that would work,
though would be curious as to the theory on how it would work.

You still need to adjust the CLOCK#2 signal of the Si5351 and turn off
the other two CLOCKs.

To do as you are suggesting, you could install a switch between the
CW-KEY and R104 to connect R104 to the CW-KEY or to a variable resistor
to adjust the voltage that is connected between the CW-KEY and R104.
Throw the switch and then press the CW key/PTT to get a lower level tune
signal. Switch it back to do the normal operation. It would require
that the CW mode be straight key, not keyer and that the CW mode is set
in the v6 (not required in prior versions, just need the CW key connected).

Above are speculations, so I could be off.
73
Evan
AC9TU


Evan Hand
 

Vince,
I have not tried to use a variable voltage on the mixer diodes to control power through the unbalanced ring.  Not sure if that would work, though would be curious as to the theory on how it would work.

You still need to adjust the CLOCK#2 signal of the Si5351 and turn off the other two CLOCKs. 

To do as you are suggesting, you could install a switch between the CW-KEY and R104 to connect R104 to the CW-KEY or to a variable resistor to adjust the voltage that is connected between the CW-KEY and R104.  Throw the switch and then press the CW key/PTT to get a lower level tune signal.  Switch it back to do the normal operation.  It would require that the CW mode be straight key, not keyer and that the CW mode is set in the v6 (not required in prior versions, just need the CW key connected).

Above are speculations, so I could be off.
73
Evan
AC9TU


Vince Vielhaber
 

Not EXACTLY. The nano puts out 5V. I said to vary the voltage to get less out.

Vince.

On 01/19/2021 09:30 PM, Jerry Gaffke via groups.io wrote:
CW-KEY is doing exactly the same thing.
When transmitting CW, CLK2 is programmed to be at the transmit
frequency, CLK0 and CLK1 are shut down,
and a Nano IO pin drives 5v on CW-KEY to unbalance the mixer.

Jerry, KE7ER

On Tue, Jan 19, 2021 at 05:57 PM, Vince Vielhaber wrote:

To get less than full power out, you can vary the voltage from 0-5v.
TP13 (it looks like TP13 anyway) would be a good place to inject
that variable voltage, you'd probably want to use a diode and
resistor in line.

I did that on my B40 and it worked well. I put the pot right on the
front panel.

Vince.


Jerry Gaffke
 

CW-KEY is doing exactly the same thing.
When transmitting CW, CLK2 is programmed to be at the transmit frequency, CLK0 and CLK1 are shut down,
and a Nano IO pin drives 5v on CW-KEY to unbalance the mixer.

Jerry, KE7ER


On Tue, Jan 19, 2021 at 05:57 PM, Vince Vielhaber wrote:
To get less than full power out, you can vary the voltage from 0-5v. TP13 (it looks like TP13 anyway) would be a good place to inject that variable voltage, you'd probably want to use a diode and resistor in line.

I did that on my B40 and it worked well. I put the pot right on the front panel.

Vince.


Vince Vielhaber
 

On 01/19/2021 08:22 PM, Evan Hand wrote:
Frank,

It is not clear to me what you are asking. If you have a uBITX then the
method that Bob describes is the easiest. If your question is how to do
that, then here is the way that it is done in the v3 and later,
displaying the v6 schematic:


The way that works is that the first mixer (T1 and T2) is being
unbalanced by a 5 volt signal from the Nano on the CW-KEY line. This
forward biases 2 of the diodes in the mixer and allows the LO signal
that has been changed to the frequency that is to be transmitted to be
applied to the amplifier stages.



It should be noted that the power output will be the full power for that
band.
To get less than full power out, you can vary the voltage from 0-5v. TP13 (it looks like TP13 anyway) would be a good place to inject that variable voltage, you'd probably want to use a diode and resistor in line.

I did that on my B40 and it worked well. I put the pot right on the front panel.

Vince.
--
K8ZW http://www.metalworkingfun.com http://www.hamradio.fun


Rafael Diniz
 

Just set CW keyer to hand-key and key the radio, you'll get a continuous
CW for tuner adjustment. I'm adding a "TUNE" button in my ubitx v6
interface code for this.

Rafael

On 1/19/21 8:30 PM, kg9hfrank@gmail.com wrote:
This past weekend, I went back in time and reviewd posts back to 2018.

About half way through I started taking notes but... I did not take
any notes on how to unbalance the balanced modular to get a signal out
for using a tuner.

Anyone have that info available?  

If I recall the ham disabled a resistor causing an imbalance and a
steady signal came out which he used to tune his tuner.  He turned it
on and off with a toggle switch.

--
Frank, KG9H


Evan Hand
 

Frank,

It is not clear to me what you are asking.  If you have a uBITX then the method that Bob describes is the easiest.  If your question is how to do that, then here is the way that it is done in the v3 and later, displaying the v6 schematic:


The way that works is that the first mixer (T1 and T2) is being unbalanced by a 5 volt signal from the Nano on the CW-KEY line.  This forward biases 2 of the diodes in the mixer and allows the LO signal that has been changed to the frequency that is to be transmitted to be applied to the amplifier stages.  



It should be noted that the power output will be the full power for that band.

The other way would be to use FT8 software or similar to generate an audio tone that can be adjusted in level for the power needed to activate the tuner.

A third option would be tu use CW-TONE or generate a tone on the unused A7 pin to feed the mic input through a variable resistor.  This would take modifiying the Nano code.

Of the three, I use either the CW or Audio tone from FT8 software.

73
Evan
AC9TU


Bob Lunsford
 

Simple way is to use the Manual Key option and CW mode to use the PTT for a +/-10W CW signal that will tell the tuner what frequency to center on for tuning. Maybe someone else can suggest a hard-wire way but this for me is the simplest way.

Bob — KK5R

On Tuesday, January 19, 2021, 6:30:47 PM EST, kg9hfrank@... <kg9hfrank@...> wrote:


This past weekend, I went back in time and reviewd posts back to 2018.

About half way through I started taking notes but... I did not take any notes on how to unbalance the balanced modular to get a signal out for using a tuner.

Anyone have that info available?  

If I recall the ham disabled a resistor causing an imbalance and a steady signal came out which he used to tune his tuner.  He turned it on and off with a toggle switch.

--
Frank, KG9H


kg9hfrank@gmail.com
 

This past weekend, I went back in time and reviewd posts back to 2018.

About half way through I started taking notes but... I did not take any notes on how to unbalance the balanced modular to get a signal out for using a tuner.

Anyone have that info available?  

If I recall the ham disabled a resistor causing an imbalance and a steady signal came out which he used to tune his tuner.  He turned it on and off with a toggle switch.

--
Frank, KG9H