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Re: Baofeng Microphone for uBITX #microphone

 

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I am REALLY happy with my -24DB cartridge homemade Mike. The Sbitx ?needs a good bit of audio signal input. I think this is a great chance for a cottage industry to develop selling these mics and shipping them, with the right connector, shielded cable is possible, and wwith really high output. ?

It’s somewhat labor-intensive. But somebody could probably automate the process a bit. Then I think you could sell these microphones for anywhere between $30 and $50 and have a pretty good business. ?

Gordon Kx4z?



On Oct 22, 2023, at 09:15, Aaron K5ATG <Aaron@...> wrote:

?Thanks for the replies.?
--
'72
Aaron?
Re: sBitx V2 SN #141 Spurious/Harmonic Measurements

 

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Thanks Evan. Yes we need confirmation. One way or the other. Either I’m doing something wrong, or my unit is a complete fluke, or there’s a problem!

I’m not sure why anyone would bother developing software for a radio that might not be legal to operate…..

What if ?only 25% of the units have a problem? But that still way way too high!! ? This is a groundbreaking transceiver and it should not be troubled by these kinds of problems. ?We certainly fixed them on the developer unit. ?And my measurements there may have been clouded by the Heathkit Cantana so it may be even better than I know! ?

The bypassing issue I think is important for the 470 ohm resistors. ?Only c204 protects at that end —-Adding several more may help. Also between the 470 and the indconductors may help

It’s dicey to slow down the switchover with capacitors on the 470 K. ?Theoretically, into a 50 ohm system, the 470 K alone provides better than 60 DB isolation. ?So I’m not sure a lot needs to be done there. Maybe a few picofarads? ?The output of the RF voltage doubler has a few hundred picofarads already. ?so it provides some significant isolation. ?

I think the real issues are the +12 line, where RF energy can get back into earlier stages and wreck havoc as far as spurious responses there, !!!!! and maybe just maybe on the ground line itself which I hope is solid. ?

The QDX seem to show that it’s possible to fix all of this. But we’re running a lot more RF current through those diodes than it did. ?I don’t know if we need additional diode’s in parallel at the output, I just don’t know. ?? A text jig fixture and a good clean commercial transceiver might be able to prove this— run the RF through a turned-on 1N4007 and measure the spurious response afterwards; this would also be a way to select preferred diodes ?for this service

I’ll be back to Gainesville in about 10 days and then I may be able to start measurements again. ?

I don’t know how many other people have quality test set up such as the Siglent or Rigol spectrum analyzer‘s but we could sure use some data; as my finances allow I’m going to buy a higher power RF pad so I can easily tolerate the full output for some time. ??

Thanks for your thoughts!

Gordon?



On Oct 22, 2023, at 07:15, Evan Hand <elhandjr@...> wrote:

?Gordon,

If it is passed through on the bias circuit, would adding some capacitors help?? Every connection of the bias to the LPF circuit may need to be bypassed.

dummyfile.0.part

This might mess up the filters instead of helping.

So far, you are the only one that is reporting an issue.? It would help if others verified that there is an issue with other V2 sbitx or for HFSignals to respond with measurements from the production units that have been tested.

73
Evan
AC9TU

Re: An alternative for sBitx software development

 

I am also using VS Code with the git, remote-ssh, and C language extensions. Works great.?
Re: Baofeng Microphone for uBITX #microphone

 

Thanks for the replies.?
--
'72
Aaron?
#sbitx #speaker #sBitx #speaker

 

Hi. What's the part number / name / type of the speaker plug J10? Thx.
Re: Baofeng Microphone for uBITX #microphone

 

I saw this one too, but I'm not sure it would work on the uBitx, because the mic for the uBitx has only three connections on the plug rather than four.? I think the difference is that the uBitx mic is just a mic, and not a speaker-mic.?

Checked my mic for a part number, but couldn't find one.? Unfortunately, so far I've not found anything for sale that looks like it matches up.?

Might need to contact hfsignals.com or gigparts.com directly to see if one could be ordered.

Another option might be to order a Baofeng speaker mic and change the connector to a 3.5mm stereo plug,? or find/build a short cable to adapt it.

73 Rolan N8LOV
Re: sBitx V2 SN #141 Spurious/Harmonic Measurements

 

Gordon,

If it is passed through on the bias circuit, would adding some capacitors help?? Every connection of the bias to the LPF circuit may need to be bypassed.



This might mess up the filters instead of helping.

So far, you are the only one that is reporting an issue.? It would help if others verified that there is an issue with other V2 sbitx or for HFSignals to respond with measurements from the production units that have been tested.

73
Evan
AC9TU

Re: Baofeng Microphone for uBITX #microphone

 

Hi,
may be you are looking for this:

?

73 Norbert DH5JW

Aaron K5ATG <Aaron@...> schrieb am Sa., 21. Okt. 2023, 23:38:

I am hoping that someone could help me out and provide me with a link on where I can purchase a Baofeng microphone. I'm referring to the one that comes with the uBITX, the hand microphone that looks like it is for an HT but it has just the one pin instead of 2 pins.?
Thank you
--
'72
Aaron?
Re: #sBitx FFTW3 libraries #sBitx

 

amazing.
Gordon KX4Z


On Sat, Oct 21, 2023 at 8:13?PM Ashhar Farhan <farhanbox@...> wrote:
Mark,
I thought (without really confirming this) that the rpi zero is 32 bit and hence it will work much faster with single precision math hence decided on single precision fft?
The fftw? library didn't build the single precision directly, you had to first build the double precision version and then build the single precision, hence the mixup.
With RPI, now that the GPU FFT library is available, the proper thing to do would be to use that, I saw someone had written a wrapper around it to be a drop-in replacement for the fftw. This will shave off many cycles from the cpu consumption.
Interestingly, I ran gprof on sbitx, the timr spent on fftw is minor. Most of the cpu cycles were spent in other loops in rx_process that copy samples and bins around. There must be some DMA kind of a way to do this.
- f

On Sun, Oct 22, 2023, 1:09 AM Mark Erbaugh <mark.election@...> wrote:
I noticed that the stock firmware uses both the standard (double) and float FFTW3 libraries. The install instructions have you build both library versions. It looks like the float libraries are only used in fft_filter.c, the standard libraries are used elsewhere. Is there a reason that fft_filter.c doesn't use the standard library?

FWIW, I modifed the code to use the standard library in fft_filter and build the program with just the standard library and everything seemed to work.

Then, I changed all the code to use just the float library. It seems to work also and at least on receive (I haven't tried transmit), it seems to sound fine. Does the program need the precision of the standard library? Does using the float library speed up the FFT process?
--
73,
Mark, N8ME

Re: #sBitx FFTW3 libraries #sBitx

 

Mark,
I thought (without really confirming this) that the rpi zero is 32 bit and hence it will work much faster with single precision math hence decided on single precision fft?
The fftw? library didn't build the single precision directly, you had to first build the double precision version and then build the single precision, hence the mixup.
With RPI, now that the GPU FFT library is available, the proper thing to do would be to use that, I saw someone had written a wrapper around it to be a drop-in replacement for the fftw. This will shave off many cycles from the cpu consumption.
Interestingly, I ran gprof on sbitx, the timr spent on fftw is minor. Most of the cpu cycles were spent in other loops in rx_process that copy samples and bins around. There must be some DMA kind of a way to do this.
- f

On Sun, Oct 22, 2023, 1:09 AM Mark Erbaugh <mark.election@...> wrote:
I noticed that the stock firmware uses both the standard (double) and float FFTW3 libraries. The install instructions have you build both library versions. It looks like the float libraries are only used in fft_filter.c, the standard libraries are used elsewhere. Is there a reason that fft_filter.c doesn't use the standard library?

FWIW, I modifed the code to use the standard library in fft_filter and build the program with just the standard library and everything seemed to work.

Then, I changed all the code to use just the float library. It seems to work also and at least on receive (I haven't tried transmit), it seems to sound fine. Does the program need the precision of the standard library? Does using the float library speed up the FFT process?
--
73,
Mark, N8ME

Re: #sBitx FFT filtering question - answer #sBitx

 

I think I figured it out. The agc2() routine was only adjusting the imaginary part. I changed it to work on the real part and it works.
--
73,
Mark, N8ME
Baofeng Microphone for uBITX #microphone

 

I am hoping that someone could help me out and provide me with a link on where I can purchase a Baofeng microphone. I'm referring to the one that comes with the uBITX, the hand microphone that looks like it is for an HT but it has just the one pin instead of 2 pins.?
Thank you
--
'72
Aaron?
Re: sBitx V2 SN #141 Spurious/Harmonic Measurements

 


The sBitx appears to be using the same improved inductors that the QDX switched to after early problems. ?But I’m still seeing some bleed around. ? It looks like Ashhar is providing about six times the bias current for the 1N4007’s. ? We are running about 2 to 5 times the power output, but the current wouldn’t be increased but by the square root of that amount. ? And where I’m seeing the problem is on the higher bands —not the lower freq bands where you would think the charge carriers would be hard-pressed to stick around long enough. ? ? Not sure if carefully selecting the diode’s or running 2 in parallel would make an improvement?

gordon
#sBitx FFTW3 libraries #sBitx

 

I noticed that the stock firmware uses both the standard (double) and float FFTW3 libraries. The install instructions have you build both library versions. It looks like the float libraries are only used in fft_filter.c, the standard libraries are used elsewhere. Is there a reason that fft_filter.c doesn't use the standard library?

FWIW, I modifed the code to use the standard library in fft_filter and build the program with just the standard library and everything seemed to work.

Then, I changed all the code to use just the float library. It seems to work also and at least on receive (I haven't tried transmit), it seems to sound fine. Does the program need the precision of the standard library? Does using the float library speed up the FFT process?
--
73,
Mark, N8ME
Re: sBitx Raspios Bookworm

 

Thanks.

You mentioned you maintain a fork of WiriingPi. I've heard that the reason Raspberry Pi dropped it from their repo's was because the original developer stopped work on the project. Do you know if the RPi people are coming out with an official way to manipulate GPIO pins from software? It seems odd that that feature is missing from the official operating systems.
--
73,
Mark, N8ME
Re: #sBitx Telnet server #sBitx

 

P.S. The frequency didn't change on the sBitx.
--
73,
Mark, N8ME
Re: #sBitx Telnet server #sBitx

 

Thanks for the reply.? I typed "f 7050" into the telnet client and the screenshot shows what I got.


--
73,
Mark, N8ME

Re: sBitx V2 SN #141 Spurious/Harmonic Measurements

 

?

In the light of what Evan pointed out about the inductors series resonances in another project, consider the trace below. ? This is the transfer function from the input of the switched low pass filter system all the way to the antenna, when no particular band is enabled. ?


at the time I was making the measurements this didn’t make any sense to me. But now you can see that it clearly shows that there are paths AROUND the filters, and sometimes they are as passable as -25db or so!!! ?This trace should be 2 MHz to 52 MHz so that big spike is somewhere in the low 30 MHz range. ??

That would appear to be a huge problem for the purity of the output signal, right? ?You want the bleed around to be way less than -45 DB.?

if the inductors have series resonances, and the filtering isn’t perfect on powerlines, then signal can get right across. ?Escaping the filters and creating havoc on the output.?


this is another possible improvement
gordon Kx4z?
Re: #sBitx Telnet server #sBitx

 

The commands are the labels on the controls. For instance "RIT ON" or "RIT OFF".


On Sat, Oct 21, 2023, 9:18 PM Ashhar Farhan <farhanbox@...> wrote:
Try "f 7050" to change to 7050 khz. "m usb", etc.


On Sat, Oct 21, 2023, 7:15 PM Mark Erbaugh <mark.election@...> wrote:
Looking in the source code file remote.c, I see that sBitx supports a telnet server on port 8081. Using the telnet client built into Windows 10, I can connect to the server about 1 time in 3. When it doesn't connect I get a message 'unable to connect'. When I do connect, the screen clears and prints "sbitx v2.0" at the top. But what can I do at that point. If I type an 'f' I get the response shown in the screen shot.
--
73,
Mark, N8ME
Re: #sBitx Telnet server #sBitx

 

Try "f 7050" to change to 7050 khz. "m usb", etc.


On Sat, Oct 21, 2023, 7:15 PM Mark Erbaugh <mark.election@...> wrote:
Looking in the source code file remote.c, I see that sBitx supports a telnet server on port 8081. Using the telnet client built into Windows 10, I can connect to the server about 1 time in 3. When it doesn't connect I get a message 'unable to connect'. When I do connect, the screen clears and prints "sbitx v2.0" at the top. But what can I do at that point. If I type an 'f' I get the response shown in the screen shot.
--
73,
Mark, N8ME
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