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Re: sBITX Toolbox - A great companion for the sBitx transceiver is now available for public release #file-notice #sBitx #sbitx_v2 #sBITX_v3 #wiki-notice

 

I have just installed the toolbox on my Sbitx v3, when runner the scanner it gives an error that telnet port not open, not sure hoe to do it need help , the toolbox is great tks.
Re: sBitxv3.02 logging

 

I use sbitx v3.02 to save ft8 QSO auto log file. After starting the program, I don't have to enter the LOG file anymore. The modification can be found on github a few days ago.
Since I have been constantly testing it since its release, I can safely say that in ft8 mode, the QSO is saved automatically and without error after switching on.

The complex call signs listed in the previous message are not displayed in ft8 mode and they cannot be recorded in the log file either. Due to its size and light weight, the device can be ideally used for camping and radio broadcasting from other areas. Due to the lack of storage of complex call signs, the special call sign cannot be recorded.
This problem has been solved in other programs designed for digital plants. I'm no coder, but I understand those source files are available.

I am painfully careful not to call stations with these call signs. But I can't avoid it when I'm called by such a station, whose callsign I can see so much <...>.
Every time I answer: callsign not decode or use short callsign. I would like a contractor who can code to fix this problem. The call sign is also not visible in the reception window. The log file cannot store these characters either.
--
Gyula HA3HZ
Which Version?

 

Hi there, I'm new to the forum altho' a long time RF builder of things.

I'm somewhat confused by all the vesrsions of BITx and am looking for an SMT version as I no longer use thru' hole components.

Could someone point me towards a PCB design for such, Eagle (as I can import) or Gerber as I'd like to make some up.

Regards to ALL.

Stretchy.
Re: ubitx audio amp problem discovered

 

I only have the 2019 version of the ARRL Handbook, but the emitter follower ("common collector") amplifier?(which has no voltage gain) is covered in Chapter 4.? Presuming the prior stage remains within linear bounds, the collector of the prior stage will be somewhere between a few volts above ground, and the Vcc voltage for the circuit.? ?Thus the base of a directly connected emitter follower will be between a few volta above ground, and the Vcc voltage for the circuit, also.? ?The emitter will always be forward biased (unless there is some HUGE capacitance on its output that keeps the emitter from decreasing its voltage when needed!) and the emitter will always be 0.6 volts lower than the base.? ? The circuit is basically a buffer, and that is discussed in the ARRL Handbook.? ?It is a nifty circuit that is very often used in linear power supplies, where a voltage reference can be established by a low-current device such as a zener diode or linear op amp, and the emitter follower can then provide current amplification when needed to drive a much heftier currrent draw.

Hope that helps!? I don't have a basic book of electronics, but I bet this concept would be covered in many of those type texts, and in many places on the Internet.

73
Gordon KX4Z


On Mon, Feb 19, 2024 at 9:52?AM AndyH <awhecker@...> wrote:
Thank you, Farhan.? I don't yet understand how to ensure the directly coupled follower stays biased 'on' in all conditions. I'll keep at it.

Best, Andy

On Sun, Feb 4, 2024 at 11:50 PM, Ashhar Farhan wrote:
There emitter follower's base can directly couple to the original's collector.
- f

On Mon, Feb 5, 2024, 10:18 AM AndyH <awhecker@...> wrote:
Farhan,

? ?Would you sanity check this, please? It's the uBITX V6 mic amp through C63 with a buffer pulled from Eamon Skelton's book.? Did I translate your suggestion accurately?

? ? Thanks and 73,
? ? ?Andy



On Sat, Jul 15, 2023 at 09:18 PM, Ashhar Farhan wrote:
Thanks for the analysis. There are two other significanr issues with the current mic amplifier.
1. The output impedance is 1000 ohms, the modulator needs a 50 ohms drive.
2. The gain is not less but too much. The electrer mic produces about 50mV of audio, the modulatoe needs less than 150mv drive. A gain of two or three is more than sufficient. The apparent loss is due to the mismatch between the 1000 ohm output and the needed 50 ohms drive.
These can be solved by adding an emitter follower with a 47 ohms resistor in series with the output of the emitter follower and removing the emitter bypass of the original mic amplifier.
- f

On Sun, Jul 16, 2023, 7:22 AM Dan Damon <dan.g.damon@...> wrote:
I've been working on the uBitx audio circuit for a while now and I think I've discovered a problem that I've never seen anyone mention before. If anyone has experience with this circuit, please review and let me know if I've missed anything. Here are my notes:
?

?Audio Amp notes.

?

The uBitx has always had challenges with the audio amp. It has insufficient gain for the condenser mic that is provided. Solutions include:

?

a. Use a mic with an amplifier built in.

b. Add an additional amplification stage such as the SSM2167.

c. Increase the mic circuit gain.

?

Mic amplifier circuit with suggested modifications. Also showing the load of the following stage.

?

SEE ATTACHED FILE

?

Analysis:

Given that the receive transistor Q70 is connected directly to the output of the microphone amplifier, the output of the mic amp must be less than 0.6v. We¡¯ll say 550 mV to give us a bit of safety margin.

The input drive required to achieve 550mV out of the mic amp is 200mV. Most have claimed that the mic amp has a gain of around 20 due to the collector resistance of 1k divided by the emitter resistance of 47 ohms. This simple analysis is incorrect because it neglects the load impedance of the mixer circuit. Spice analysis and actual observation shows the actual gain to be about 2x or 3x.

A big problem with this mic amplifier is that it is incorrectly biased. With the originally specified bias resistor R61 set at 2.2k, the transistor runs out of emitter current at about 160mV of output voltage. In addition to limiting output, this causes distortion of the audio waveform. By increasing R61 to 10k, the circuit can easily output the 550 mV (1.1V P-P) originally suggested.

In my own uBitx, I have chosen to use the SSM2167 as a preamp in order to enjoy some voice compression. However, the simplest solution is to decrease R63 to 10 to 22 ohms. I¡¯d advise not to go lower than 10 ohms, since that circuit should fully drive the mixer with a mic output of only 40 mV. But before doing anything else, increase R61 to 10K.

?

?

?
Re: ubitx audio amp problem discovered

 

Thanks for your thoughts, Dave. The V6 I have on board, that I ordered a bit more than a year ago, has the new hand mic you mentioned.? The earlier V3 and V6 radios I have in storage have the earlier mics. I missed the posts about stuffing foam or cotton into the case - good info!

I do have a couple of the various mic preamp boards mentioned in this and other threads, and like that one offers the option of compression. I may look at compression once I figure out how to buffer the amp in the radio.

Thanks again.
Andy, KG5RKP/MM


On Wed, Jan 31, 2024 at 10:09 PM, DaveW, KL7HJF wrote:
Andy,
If your problem is microphone audio quality on transmit from uBitx V6 (and other versions), there has been a lot of forum discussion about using different microphones, or improving the microphone supplied with the radio.

I think some radios were supplied with Baofeng microphones, which had low quality electret mic elements. Audio was sometimes improved by finding a better quality compatible mic element.??

My uBitxV6 came with a different microphone. The internal circuit board is labeled "hamshack.in". The transmit audio was reported as very poor. I confirmed this by hooking the mic to my computer mic input through a simple circuit which provided dc bias to the electret mic, I recorded the audio as I spoke, then played it back. (The computer didn't supply proper bias.) In any case, the audio was muffled and nearly unintelligible.

I had a couple of used electret mic elements (quality and specs. unknown) in my junk box. I installed them, one at a time, and tested with similar results. But I noticed that, if tested outside of the microphone housing, all three mic elements had reasonably good audio. Apparently, there were echoes inside the hollow case. The fix was to add some soft foam padding inside the case (filling the lower case, with a thinner layer behind the holes on the case front, to cover the mic element, circuit board, and space in the upper case). I saw another forum thread where someone stuffed the case with cotton. The improvement was remarkable... and did not require any modification to the radio.

Also note that transmit audio can also be poor, if the BFO calibration is not right.

Simple bias circuit (for testing mic element with computer):? Use a 9 volt battery. Connect negative lead to ground side of mic element. Connect positive lead through a 10K resistor to the positive side of the mic element. Also connect a 10 ufd capacitor (+ side) to the positive side of the mic element. (These exact resistor and capacitor values are not required. Use the closest that you have). Bias circuit is complete. Connect to computer: Negative side of mic (and battery)? to ground of mic plug; Negative side of capacitor to mic input terminal of mic plug.
Re: ubitx audio amp problem discovered

 

Thank you, Farhan.? I don't yet understand how to ensure the directly coupled follower stays biased 'on' in all conditions. I'll keep at it.

Best, Andy


On Sun, Feb 4, 2024 at 11:50 PM, Ashhar Farhan wrote:
There emitter follower's base can directly couple to the original's collector.
- f

On Mon, Feb 5, 2024, 10:18 AM AndyH <awhecker@...> wrote:
Farhan,

? ?Would you sanity check this, please? It's the uBITX V6 mic amp through C63 with a buffer pulled from Eamon Skelton's book.? Did I translate your suggestion accurately?

? ? Thanks and 73,
? ? ?Andy



On Sat, Jul 15, 2023 at 09:18 PM, Ashhar Farhan wrote:
Thanks for the analysis. There are two other significanr issues with the current mic amplifier.
1. The output impedance is 1000 ohms, the modulator needs a 50 ohms drive.
2. The gain is not less but too much. The electrer mic produces about 50mV of audio, the modulatoe needs less than 150mv drive. A gain of two or three is more than sufficient. The apparent loss is due to the mismatch between the 1000 ohm output and the needed 50 ohms drive.
These can be solved by adding an emitter follower with a 47 ohms resistor in series with the output of the emitter follower and removing the emitter bypass of the original mic amplifier.
- f

On Sun, Jul 16, 2023, 7:22 AM Dan Damon <dan.g.damon@...> wrote:
I've been working on the uBitx audio circuit for a while now and I think I've discovered a problem that I've never seen anyone mention before. If anyone has experience with this circuit, please review and let me know if I've missed anything. Here are my notes:
?

?Audio Amp notes.

?

The uBitx has always had challenges with the audio amp. It has insufficient gain for the condenser mic that is provided. Solutions include:

?

a. Use a mic with an amplifier built in.

b. Add an additional amplification stage such as the SSM2167.

c. Increase the mic circuit gain.

?

Mic amplifier circuit with suggested modifications. Also showing the load of the following stage.

?

SEE ATTACHED FILE

?

Analysis:

Given that the receive transistor Q70 is connected directly to the output of the microphone amplifier, the output of the mic amp must be less than 0.6v. We¡¯ll say 550 mV to give us a bit of safety margin.

The input drive required to achieve 550mV out of the mic amp is 200mV. Most have claimed that the mic amp has a gain of around 20 due to the collector resistance of 1k divided by the emitter resistance of 47 ohms. This simple analysis is incorrect because it neglects the load impedance of the mixer circuit. Spice analysis and actual observation shows the actual gain to be about 2x or 3x.

A big problem with this mic amplifier is that it is incorrectly biased. With the originally specified bias resistor R61 set at 2.2k, the transistor runs out of emitter current at about 160mV of output voltage. In addition to limiting output, this causes distortion of the audio waveform. By increasing R61 to 10k, the circuit can easily output the 550 mV (1.1V P-P) originally suggested.

In my own uBitx, I have chosen to use the SSM2167 as a preamp in order to enjoy some voice compression. However, the simplest solution is to decrease R63 to 10 to 22 ohms. I¡¯d advise not to go lower than 10 ohms, since that circuit should fully drive the mixer with a mic output of only 40 mV. But before doing anything else, increase R61 to 10K.

?

?

?
Re: sBITX V2 S-Meter?

 

I think Ashhar already has a somewhat-calibrated graphical display of signal level, which probably is in some factor of "dBm"??

S-meters are notoriously?variable and unreliable, but there does exist a published standard.? ?An enterprising coder could take the signal level and make an image that would?approximate a moving S-meter or moving bar, with a bit of delay so peaks could be read.? ?I think this would be appreciated by a lot of users.? ?

My 2 cents!!!? ? I'll be presenting the radio Saturday at the West Central Florida TECHCON, and it is a greatly improved story this year!? Very fascinating radio and at an amazing pricepoint.
Gordon KX4Z


On Mon, Feb 19, 2024 at 4:18?AM Paul <g0kaohx@...> wrote:
Ashar
Not sure if S-Meter is anywhere near on the horizon yet, just a suggestion perhaps but maybe a numeric indicator to the side of the grey bars on the audio spectrum? might be useful, not accurate but maybe a useful indicator. by setting the noise floor to the bottom of the display using the IF control, then a rough indication based on the waveform peaks might provide a useful indication of a possible S-Point value indication.?
I am not a coder per-se, this might perhaps be just a UI modification to start with until a proper s-meter is deployed to give a rough indicator

Regards
Paul

Re: Bitx40 issues, version 2

 

The early BitX radios had a separate power connection for the finals, Q15 in the case of the BitX40. This was so you could run higher voltages there to increase power output while the rest of the rig ran at 12v. Typically that separate line is just connected to the 12v and it is wired that way on the latest V6 uBitX. Check to see if that is connected on yours.

=Vic=
Re: sBitx with ESP32 #esp32 #sBitx

 

Hi Ramon

This is fascinating. Since the Weaver method doesn't need an SSB filter, does this work without the 40MHz filter in the sBitx?
I note that the ESP32-LyraT board is available very cheaply - in fact?cheaper than a MIKROE codec board I bought to graft onto a Raspberry Pi.
This looks like a great route to play with yet more designs of transceiver.

Tony



On Sun, 18 Feb 2024 at 18:50, <ramonlh@...> wrote:
Hi,
SSB demodulation with an ESP32 is already working. I have changed the method followed in the sBitx to the Weawer method as described by Derek Rowell in


I have used the "Audio-Demod" output of the sBitx that I have applied to the input of an ESP32-LyraT board. The basic demodulation diagram is

It is programmed with the Espressif-IDE environment with the Espressif ESP-DSP libraries and the process is almost as simple as that used in the original sBitx.
This is the part of code that decodes the SSB at 24khz:
static void audio_modem_task3(void *pvParameters)??? ??? // Weawer method
{
?? ?xSemaphore = xSemaphoreCreateMutex();
?? ?size_t bytes_read = 0;
??? // Create cos & sin tables
?? ?float f_carrier = 24000;
?? ?float f_bfo = 1500;
?? ?float freq_carrier = f_carrier / 96000;
?? ?float freq_bfo = f_bfo / 96000;
??? dsps_tone_gen_f32(cos_carrier, N, 1, freq_carrier, 0);??? ??? // generate carrier cos
??? dsps_tone_gen_f32(sin_carrier, N, 1, freq_carrier, 90);??? ??? // generate carrier sin
??? dsps_tone_gen_f32(cos_bfo, N, 1, freq_bfo, 0);??? ??? ??? ??? // generate bfo cos
??? dsps_tone_gen_f32(sin_bfo, N, 1, freq_bfo, 90);??? ??? ??? ??? // generate bfo sin
??? while (1) {
??? // Step 0, read samples
?? ???? // 1024 4-byte samples are read, 1024 from the left channel and 1024 from the right channel
?? ???? i2s_read(I2S_NUM_0, samples, I2S_BUFFLEN, &bytes_read, portMAX_DELAY);??? // le¨ªdos 8192 bytes, 4x1024 left, 4x1024 rigth channel
?? ?// Step 1, copy samples to frf[]
?? ???? for (int i=0; i<N;i++) frf[i] = (float) samples[2*i] / 100000;? // rigth channel
?? ?// Step 2, multiply frf * cos_carrier & frf * sin_carrier
?? ???? dsps_mul_f32_ae32(frf, cos_carrier, f1, N_SAMPLES, 1,1,1);??? // multiply cos
?? ???? dsps_mul_f32_ae32(frf, sin_carrier, f2, N_SAMPLES, 1,1,1);??? // multiply sin
??? // Step 3, low pass filter 300-3000? TO DO
?? ???? float freq_t = 3000;
?? ???? float ft = freq_t/96000;
?? ???? generate_FIR_coefficients(fir_coeffs, FIR_COEFFS_LEN, ft);??? ??? ??? // Calculate 64 coefficients for the FIR filter
?? ???? dsps_fir_init_f32(&fir1, fir_coeffs, delay_line, FIR_COEFFS_LEN);??? // init fir filter
?? ???? dsps_fir_f32_ae32(&fir1, f1, f3, N_buff);? // Filter the input signal with FIR filter, f1 --> f3
?? ???? dsps_fir_f32_ae32(&fir1, f2, f4, N_buff);? // Filter the input signal with FIR filter, f2 --> f4
??? // Step 4,? multiply f3 * cos_bfo & f4 * sin_bfo
??????? dsps_mul_f32_ae32(f3, cos_bfo, f1, N_SAMPLES, 1,1,1);??? // multiply cos?? f5
?? ???? dsps_mul_f32_ae32(f4, sin_bfo, f2, N_SAMPLES, 1,1,1);??? // multiply sin?? f6
??? // Step 5,??? add f5 + f6 = f7
?? ???? dsps_add_f32_ae32(f1, f2, frf, N, 1,1,1);??? // f1=f5,?? f2=f6,?? frf=f7
??? // we copy the output in frf[] to the samples[] variable to send it to I2S
?? ???? for (int i=0;i<N;i++) samples[2*i]=10000000* frf[i];
?? ???? i2s_write(I2S_NUM_0, samples, I2S_BUFFLEN, &bytes_read, portMAX_DELAY);
?? ???? xtimes++;
?? ???? vTaskDelay(1 / portTICK_PERIOD_MS);
??? }
??? vTaskDelete(NULL);
}

I need to integrate it with the part that controls the sBitx, another ESP32 with a 2.8" screen, which is basically an adaptation of the Raduino32 software that I used with the uBitx v6.
/g/BITX20/message/90933
I don't know if it will be useful, I hope so, but it has been a good learning experience.

Saludos,
Ram¨®n EA4GZI

Re: sBITX V2 S-Meter?

Paul
 

Ashar
Not sure if S-Meter is anywhere near on the horizon yet, just a suggestion perhaps but maybe a numeric indicator to the side of the grey bars on the audio spectrum? might be useful, not accurate but maybe a useful indicator. by setting the noise floor to the bottom of the display using the IF control, then a rough indication based on the waveform peaks might provide a useful indication of a possible S-Point value indication.?
I am not a coder per-se, this might perhaps be just a UI modification to start with until a proper s-meter is deployed to give a rough indicator

Regards
Paul
Re: sBITX Toolbox - A great companion for the sBitx transceiver is now available for public release #file-notice #sBitx #sbitx_v2 #sBITX_v3 #wiki-notice

 

ps.:? This is exactly the kind of log exporter I was thinking of. Thank you very much for your work.
--
Gyula HA3HZ
Re: sBITX Toolbox - A great companion for the sBitx transceiver is now available for public release #file-notice #sBitx #sbitx_v2 #sBITX_v3 #wiki-notice

 

This v2.0 has grown quite a bit.
At first I thought that the Windows version was also included.
It is now much larger than the sbitx program itself. :-)
I tried it and I really like it!
--
Gyula HA3HZ
Re: FLDigi startup with SBitx- upgrade possible?

 

Adam,
I didn't update it, but you should know that Debian 10 Buster is used by sbitx. It is possible that this is the highest version currently installed and higher versions only work on newer Debian 11 or 12. I didn't watch that, but you can expect that.
--
Gyula HA3HZ
Re: sBitx no receive unless I restart the application

 

Dave,
when you enter the forum, you will find the wiki option in the menu on the left. You will find a lot of information there. Also, setup information from the beginning on .

I have tested many fixes so far, when I install a new one, I clone it from github if possible, then copy the previous useful and important data from the old one, and then install it (read ./build sbitx). What are the important data? The entire contents of the data folder, because it also includes hardware setting data, as well as the log database. Also, in the web folder, all macros with the .mc extension that I use with my own data.

At the end of the day, before I turn off the device, I make a copy of the daily variables. Sometimes I copy the entire sbitx folder. Even less often, the entire OS system, which is SD Copier.
However, if there is a problem, you should have a previous well-functioning program.
--
Gyula HA3HZ
Re: sBITX Toolbox - A great companion for the sBitx transceiver is now available for public release #file-notice #sBitx #sbitx_v2 #sBITX_v3 #wiki-notice

 

i am happy to announce that version 2.0 is now available. This version is another big step towards logical file management and data structure. New in this release are the addition of a Log Export application and cosmetic changes to the other apps. PLEASE READ BELOW!



Important Note: Due to the data structure changes, the configuration files for sBITX Manager and sBITX Launcher have moved. If you plan on upgrading from a version earlier than 2.0, then the data structure will be different and cause functional and appearance issues. It is highly recommended that you run the uninstaller first and DO NOT continue the upgrade from the Toolbox app update checker.?


?



-JJ
Re: Bitx40 issues, version 2

 

And I have not been able to get rid of the "power supply" hum (but it goes away when I run on my battery, so at least I know what it is!
Re: Bitx40 issues, version 2

 

Still receiving well, but no transmit output in transmit when speaking or whistling into the supplied mic. My voltages on transmit and receive seem to be fine until Q14, but that changes at Q15, and no voltages at Q15 either in transmit or receive.

I assumed that meant Q15 was bad, so I replaced it with a spare I had in another kit - but nothing has changed.?

Any next suggestions?
Re: Homebrew SBITX - no audio from codex

 

Thank you for the note... I did get it working. It was a faulty codec proto board
Re: Writing the ICOM EMULATOR for the sBitx

 

Now added a page and links to the very primitive Version 0.1 of this software.? ? It is VERY primitive folks.....lots of ways it can foul up.? ?Hopefully as I get better at this, it will become more robust.

/g/BITX20/wiki/30734

Which points to a repository of the software:? ?

There are probably better ways to store and do all of this.? ?With a virtual com port on a PC and some wizardry that I don't yet have, one could probably have all this running on the legacy PC and then simply telnet over to the V3 sBitx....but not yet.

73
Gordon KX4Z
Are International SW Broadcasts Coming Back? #uBITX_V6

 

I'm sitting here listening to the English hour of Radio Romania International on 7.325 MHz and it's bringing back some good memories!

The uBITX is smaller and less power hungry than the R390s and Racal RA6790s I used in an earlier life - yet the audio is at least as good as these old rack-mounted beasties.

73, Andy
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