开云体育

On Jan 8, 2021, at 07:24, Rafael Diniz <rafael@...> wrote:

?Perfect, I just realized that, thanks!!

Rafael

On 1/8/21 12:15 AM, Ashhar Farhan wrote:
If you put the latest firmware into the ubitx, you can key cw by
holding down the mic ptt

On Fri 8 Jan, 2021, 8:25 AM Curt via groups.io <>,
<wb8yyy@... <mailto:[email protected]>> wrote:

Yes. With older vacuum tube transmitters we used a key to tune the
final amplifier. As Mark suggests, need to set menu for hand key,
as the paddle or keyer mode produces continuous dits or dahs instead.

I am remembering wsjtx software for ft8 has a tune function,
which gives a steady audio tone as Rubens suggested. Try all of these.

Curt

If you put the latest firmware into the ubitx, you can key cw by
holding down the mic ptt

On Fri 8 Jan, 2021, 8:25 AM Curt via groups.io <>,
<wb8yyy@... <mailto:[email protected]>> wrote:

Yes. With older vacuum tube transmitters we used a key to tune the
final amplifier. As Mark suggests, need to set menu for hand key,
as the paddle or keyer mode produces continuous dits or dahs instead.

I am remembering wsjtx software for ft8 has a tune function,?
which gives a steady audio tone as Rubens suggested. Try all of these.

Curt

Hi all,

Is there any simple way (can be changing the firmware) to transmit a
continuous tone, in order I can use it to adjust a power amplifier (I
got a kit from aliexpress)?

Btw, any guide on how to use he CW over serial on the ubitx? I should
just put the radio in CW mode over CAT and then send key down and key up
for having CW on and off in the selected frequency?

Rafael PU2UIT

Or connect a push button or switch to the cw input, either internal or
external. I can do it with a piece of wire.

Curt

Hi all,

Is there any simple way (can be changing the firmware) to transmit a
continuous tone, in order I can use it to adjust a power amplifier (I
got a kit from aliexpress)?

Btw, any guide on how to use he CW over serial on the ubitx? I should
just put the radio in CW mode over CAT and then send key down and key up
for having CW on and off in the selected frequency?

Rafael PU2UIT

You will have to brew it. Program the gps module to output 10 mhz,
feed it through a 10 mhz filter and divide it by two using a flip
flop, now you get a stable 5 mhz signak, square wave.
Filter out the fifth harmonic and use that as the input to the si5351.?
It sounds complicated but it can be a single evening project

On Thu 7 Jan, 2021, 7:38 PM Rafael Diniz, <rafael@...
<mailto:rafael@...>> wrote:

Hi Ashhar,

Is there a way to know if the Si5351 correct got the 25 Mhz input?

I still did not do the 10 MHz to 25 MHz circuit (I bought a GPSDO with
10Mhz output from ebay). Any way I can buy a 10 MHz to 25 MHz
transverter already assembled?

Regards,
Rafael

On 11/19/20 12:48 AM, Ashhar Farhan wrote:
> I tried something a year ago or so. I was attempting to reduce the
> phase noise on Si5351 using an external oscillator instead of the
> internal oscillator.
> So, this is how it worked.?
> 1. You take a 10 MHz TCXO, (subsitute this with a GPS source for a
> GPSDO) and divide it by 2 in a 74HC74. The output is rich in
harmonics
> at 5 MHz.
> 2. You feed the 5 MHz square wave into a triple tuned bandpass
filter
> at 25 mhz to isolate the 5th harmonic. This will be weak, add an
> amplifier of 16 db to bring it up.
> 3. Feed this to the xin input of the Si5351.
> Now, your Si5351 is GPS disciplined.
>
> On Thu 19 Nov, 2020, 7:35 AM Rafael Diniz,
<rafael@... <mailto:rafael@...>
> <mailto:rafael@... <mailto:rafael@...>>>
wrote:
>
>? ? ?Very interesting Jason! Tks!
>
>? ? ?Rafael
>
>? ? ?On 11/17/20 10:47 AM, Jason Pirok wrote:
>? ? ?> I just bought one of the VFO/SigGen kits from QRP-Labs and
they
>? ? ?> already have a GPS disciplined option for it if you want
to try it
>? ? ?> out. It is only 1PPS but apparently does the job. I
haven't built my
>? ? ?> GPS kit yet so I can't give any personal details atm. You
have to
>? ? ?> provide the 5v supply on your own so that is some extra work.
>? ? ?>
>? ? ?> Just a thought in case you hadn't seen that project yet.
>? ? ?>
>
>
>
>
>
>

On Tue, Jan 5, 2021 at 07:49 PM, Rafael Diniz wrote:

Btw, I noticed I get zero output on 6.9MHz, and full power on
7100. Why?

I believe it is due to this section of the v6.1 code where the low
pass filter is selected:

void setTXFilters_v5(unsigned long freq){
??
? if (freq > 21000000L){? // the default filter is with 35 MHz cut-off
? ? digitalWrite(TX_LPF_A, 0);
? ? digitalWrite(TX_LPF_B, 0);
? ? digitalWrite(TX_LPF_C, 0);
? }
? else if (freq >= 14000000L){ //thrown the KT1 relay on, the 30 MHz
LPF is bypassed and the 14-18 MHz LPF is allowd to go through
? ? digitalWrite(TX_LPF_A, 1);
? ? digitalWrite(TX_LPF_B, 0);
? ? digitalWrite(TX_LPF_C, 0);
? }
? else if (freq > 7000000L){
? ? digitalWrite(TX_LPF_A, 0);
? ? digitalWrite(TX_LPF_B, 1);
? ? digitalWrite(TX_LPF_C, 0);? ??
? }
? else {
? ? digitalWrite(TX_LPF_A, 0);
? ? digitalWrite(TX_LPF_B, 0);
? ? digitalWrite(TX_LPF_C, 1);? ??
? }
}

Note that there is a small bug in the above, as the 60/80 meter filter
will be selected if the frequency is set exactly at 7MHz.? Not sure
that anyone would run that close to the band edge, but it does mean
that taking any measurements you would want to be at least a few hertz
above 7MHz.? I would have made the compare >=.? The same is true for
15m (21MHz).

You need to also take into account the sidetone offset when testing
CW, as the actual carrier is shifted by the sidetone value.? Since I
do not have a v6 I am not sure how the CWL or CWU mode is handled.?
All of my uBITX have been converted to KD8CEC firmware.? To be safe,
the best bet is to set a test frequency of 1kHz or more above the
21MHz and 7MHz filter selection points.

73
Evan
AC9TU