Re: NBFM (Was: AM on sBITX?)
But why are you not using NBFM with sBitx? Its bandwidth is by far much wider than what is needed for NBFM.
- Rafael PU2UIT
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On 10/29/24 2:14 AM, WP3DN wrote: Rafael,
I also have a 2m working system. If you would like to test any implementation of nbfm or any other mode let me know.
Juan WP3DN
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Re: Looking for flow diagram of the audio paths for sBitx v2 or v3
Sidetone is not used.
The module of the loopback or the wm8731? It is basically read and write to the device, there is no mux in the driver. If you want we can make a call I can explain what I did, and may be it will help you. Pipewire integration is an option indeed, but not the only one. Keeping just with alsa is also an option, as both pipewire and pulseaudio both can talk directly to the alsa API. I'm not an experto on the ham-radio ecosystem, so I'm not really sure if using a sound daemon is a good option. My first bet is keeping it simple - just ALSA.
- Rafael
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On 10/28/24 8:53 PM, JJ - W9JES wrote: Thanks for replying. It seems complicated to many of us especially when tiering 3rd party applications.
There is some trickery going on in software that controls the Wolfson module loaded into Linux. There is a MUX for line in/out audio The capture mix mutes on TX and the mater volume is boosted. What is sidetone used for?
I understand how the loopbacks are controlled and used. It's the module to linux to software piece that has me confused.
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Re: NBFM (Was: AM on sBITX?)
Rafael,?
?
I also have a 2m working system. If you would like to test any implementation of nbfm or any other mode let me know.
?
Juan WP3DN
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Re: FT8 sBitx v3 v4.01 Power Output
On Sun, Oct 27, 2024 at 01:44 AM, Kevin wrote:
This morning, I ran JS8Call with drive/power set to 25 watts
Kevin, pull the JS8Call "Power Slider" down to around -28dB to start with, about a quarter way up from the bottom.? At max on the power slider you will over drive the system.
?
I run my naitve sbitx at 33 on the "DRIVE" dial and with the JS8Call slider way down I get a nice 5 to 7 watts on the ATU meter.?
--
Pete VK3PYE
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Re: FT8 sBitx v3 v4.01 Power Output
It’s even more sloped than a pure percentage. 50% percent means 50% of the voltage, not the power. The power will be 1/2×1/2 of peak or 1/4 of peak. When you’re at 25% you will have 1/16 of the possible if the unit can go there?
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On Oct 28, 2024, at 12:52, Kevin via groups.io <cepagmetram@...> wrote:
? Oh snap, you're right.? The units for that field must be percentage and not watts like I was thinking.? I cranked it to '50' and it does show much higher on the power meter and the sbitx app now shows something other than zero.
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Re: NBFM (Was: AM on sBITX?)
Not yet... I'd love to see NBFM on this platform so I can effectively use my transverter for other modes.
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Re: Looking for flow diagram of the audio paths for sBitx v2 or v3
Thanks for replying. It seems complicated to many of us especially when tiering 3rd party applications.?
?
There is some trickery going on in software that controls the Wolfson module loaded into Linux. There is a MUX for line in/out audio The capture mix mutes on TX and the mater volume is boosted. What is sidetone used for?
?
I understand how the loopbacks are controlled and used. It's the module to linux to software piece that has me confused.
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Re: Looking for flow diagram of the audio paths for sBitx v2 or v3
Hi JJ,
I wrote the software we use from scratch, so I understand it very well, and it is not complicated, indeed, I can not imagine something simpler than the sbitx. What are exactly your questions?
radio rx -> WM8731 in?(one side of stereo) -> software
mic -> WM8731 in?(other side of stereo) -> software
software -> WM8731 out (one side of stereo) -> radio tx
software -> WM8731 out (other side of stereo) -> earphones / speaker
Farhan's reference implementation also uses alsa audio loopback - it just "plugs" to the rx and tx through software, of course using proper conversions when needed.
Cheers,
Rafael Diniz
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On 10/28/24 7:37 PM, JJ - W9JES wrote: I am trying to figure out the unnecessarily, complicated audio plumbing for the sBitx v2 and v3. Has found or attempted to reverse engineer this?
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Re: Looking for flow diagram of the audio paths for sBitx v2 or v3
Forgot to mention is that the main reason for understanding this current architecture is to convert it over to pipwire. I need to understand how and what it's doing before making changes.
?
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Looking for flow diagram of the audio paths for sBitx v2 or v3
I am trying to figure out the unnecessarily, complicated audio plumbing for the sBitx v2 and v3. Has found or attempted to reverse engineer this?
?
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Re: FT8 sBitx v3 v4.01 Power Output
Oh snap, you're right.? The units for that field must be percentage and not watts like I was thinking.? I cranked it to '50' and it does show much higher on the power meter and the sbitx app now shows something other than zero.
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If somebody has purchased good ones at Aliexpress it would be nice having their coordinates, I also rolled my own and, I'll start functional tests, at least the 12 Mhz works.
73s Hubert F6DUK
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Re: Sbitx bandpass filter
In the circuitry. Look at the resistoe capacitors around the T/R circuitry of 2N7000s.
On Mon, Oct 28, 2024, 7:50 AM Mike Johnshoy via <mike.johnshoy= [email protected]> wrote: thanks ... where is that done in the sbitx?
On Sun, Oct 27, 2024 at 09:55 PM, Ashhar Farhan wrote:
>
> Mike, the Rx line is derived by inverting and delaying the tx line.
>
--
Mike KB2ML
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Re: Sbitx bandpass filter
thanks ... where is that done in the sbitx?
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On Sun, Oct 27, 2024 at 09:55 PM, Ashhar Farhan wrote:
Mike, the Rx line is derived by inverting and delaying the tx line.
--
Mike KB2ML
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Re: Sbitx bandpass filter
Mike, the Rx line is derived by inverting and delaying the tx line.
On Mon, Oct 28, 2024, 7:20 AM Mike Johnshoy via <mike.johnshoy= [email protected]> wrote: Ashar, I have been studying the tr_switch code sin sbitx.c.? I see code like
digitalWrite(TX_LINE, HIGH);
which seems to control the TR switch (disconnecting the rcvr from the PA) and controlling the power to the PA.
What is the rx line you mention?
Mike
On Sun, Oct 27, 2024 at 08:36 PM, Ashhar Farhan wrote:
>
> Be careful to time the T to R transitions carefully. When starting tx, the rx
> line should go down, you wait a millisecond or so and then the tx line powers
> up.
> The transition from T to R should be similar. Power donw the T line, wait for
> a millsec or so for everything to discharge power, then turn on the R line.
>
--
Mike KB2ML
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Re: Sbitx bandpass filter
Ashar, I have been studying the tr_switch code sin sbitx.c. I see code like
digitalWrite(TX_LINE, HIGH);
which seems to control the TR switch (disconnecting the rcvr from the PA) and controlling the power to the PA.
What is the rx line you mention?
Mike
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On Sun, Oct 27, 2024 at 08:36 PM, Ashhar Farhan wrote:
Be careful to time the T to R transitions carefully. When starting tx, the rx
line should go down, you wait a millisecond or so and then the tx line powers
up.
The transition from T to R should be similar. Power donw the T line, wait for
a millsec or so for everything to discharge power, then turn on the R line.
--
Mike KB2ML
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Re: sBITX out of band transmit
Thanks for the advice. I will take a look.
--
'72
Aaron?
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Re: Sbitx bandpass filter
Ashhar,?
?
Thanks a lot for the advice!! Taking a closer look at the schematic of the gpa10 amplifier, it looks like the pa gets completly disconected when on rx. But still have to attention to the oscillations. The amp uses 1 rd16 to drive 2 rd16. So i dont want to damage those.
?
?
Juan WP3DN
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Re: sBITX out of band transmit
In the sbitx.c, there is an array that defines the band edges. You can edit them to get to your desired frequency. Remember to rebuild the program after editing it.
On Mon, Oct 28, 2024, 1:57 AM Gary Eldridge - KC8UD via <gary.video= [email protected]> wrote: On the hardware side of things you have to consider band pass filters which are band specific.
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Re: Sbitx bandpass filter
Juan,
There is lurking danger with the t/r circuitry.
As the entire receiver is bidirectional, when you go from transmit back to receive, there can a millisecond or less of time when the rx power line capacitors still hold power and the tx circuitry is powered up.
This can cause the entire power amp and the if aml to go into self oscillations. These can be very large oscillations that can blow up the finals.
Be careful to time the T to R transitions carefully. When starting tx, the rx line should go down, you wait a millisecond or so and then the tx line powers up.
The transition from T to R should be similar. Power donw the T line, wait for a millsec or so for everything to discharge power, then turn on the R line.
I meant to say from 30m to 6m
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Peter VK3PYE
Kevin
Aaron K5ATG