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sBitx Commands

 

Question:
When in an FT8 Transmission, and I want to Halt TX what is the command??
Thanks
Vince
N2AIE
Re: Transverter Location #ubitx #2meters

 

I was mistaken, my uBITX is doing right around 6 watts on 10 meters
--
'72
Aaron K5ATG
Re: Transverter Location #ubitx #2meters

 

Yes, this transverter has a maximum power input of 10 watts. My uBITX is putting out 9.6 watts on 10 Meters. That is just under the max limit of power but I think that it will be ok.?
The tuner is for 80-10 meters, not 2 Meters. The tuner tunes an end-fed antenna that is attached to my house. It is 135 feet long and with a tuner, it will give me 80-10 meters.?
The 144 MHz Transverter uses the 10 Meter band and converts it to 144 MHz. The antenna connector labeled VHF ANT, on the transverter, goes to a 5 element 2 Meter yagi antenna. This antenna has an SWR from 1.1:1 to 1.2:1 across the 2-meter band. Because the SWR on the 2 meter yagi is so low I do not need a tuner.?

The HF tuner is for my HF antenna. In order for me to operate on multiple HF bands I need a tuner for the HF bands, again I do not need a tuner for the 2 meter band.?
Everyone has become so fixated on me using a tuner for 2 meters. That was never the question.
There is a fair amount of SSB and CW activity on the 2-meter band in my area. I would like to take part in that activity. Since my uBITX does not have 2? meters, I need either a dedicated 2-meter rig that operates on SSB and CW. My FM radio does not do that. The option that is in my budget is a transverter.?
My question is should the antenna tuner be placed before or after the 2 Meter transverter.?

Has anyone ever tried to add 2 Meters to the uBITX or the sBITX? Then I would not need a separate transverter.?
--
'72
Aaron K5ATG
Re: Transverter Location #ubitx #2meters

 

As Ashar said....

Antenna tuners aare for HF only.? Any 2M beam that would need that is?
in bad shape or completely untuned (useless).

THe Radio goes to transverter and the Transverter 2M output gots to 2M antenna.

NOTE: most transverters have a maximum power input and exceeding that can destroy it.


Allison
------------------
Please use the forum, offline and private will go to bit bucket.
Re: sBitx C403 Part details

 

I'm attempting to make a simple parts list for my homebrew build but I have not progressed very far with it.?
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'72
Aaron K5ATG
Re: sBitx which filter is which?

 

Ashar,
Thanks that's what I needed.
Vince
N2AIE
Re: sBitx which filter is which?

 

Top to Down :
30- 21
14-18
7-14
3.5
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On Mon, Sep 26, 2022, 8:57 PM Vince Loschiavo <vince320@...> wrote:


Could someone mark which bands are related to which relays?
Thanks
N2AIE

sBitx C403 Part details

 

Parts list?
is it just me or I'm not looking in the right place.? Would like to know details of the Caps that are used in the filtering (ie C403) so i can get one or 2...
thanks
N2AIE
Vince
Re: sBITx shorting out #bitx20 #sBitx

Andrew
 

Mr. Farhan,

I had a moment where the IF gain was so forceful that the waterfall had turned entirely red; this was during that period when the raspberry pi digital board would shut down when transmitting. Could the WM8731 have been overdriven? Would this explain no reception input but the ability to transmit? Assuming this is where the signals come into the SDR, I could be wrong.

Andrew
sBitx which filter is which?

 



Could someone mark which bands are related to which relays?
Thanks
N2AIE

Re: Transverter Location #ubitx #2meters

 

Thank you guys
--
'72
Aaron K5ATG
Re: 16x2, 16x4 display for V6

 

Thank you Evan. Appreciate !

I will now go through the process of learning how to programme the Raduino and do this display change. Idea is to build a compact radio for portable digital use.

73
Bapi
VU2MZX
Re: 45 Mhz crystal filter

 

The mods are on ubitx.net


73
Evan
AC9TU
45 Mhz crystal filter

 

I¡¯m looking for details about the 45 Mhz crystal filter mod for v3 ubitx rf clean up. Also a part number for the Axicom relays at Mouser or Digikey would be helpful. I have seen this mentioned but not really explained. Wasn¡¯t there some surface mount inductors involved too?
Re: sBitx DE sold out

 

When setting bias, set power supply current limit to 1 or 2 A. That will prevent blown finals.

Without transistors check if you get a smooth 0-5V variation with presets.

Raj

On 26/09/2022 4:22 PM, Mark Earnest via groups.io wrote:

My finals now blow when attempting to set the bias, I¡¯m concerned I may have damaged something else as well. Is there anything in particular I should be checking?


--
KB3LYB
sBitx #077
Use driver stage as PA. #sBitx

 

5W is better than 0W

Here is my mod. Easiest done with driver fets removed.
Remove both IRFZ24. Remove C100 and C101. Unsolder orange leads from? transformer. Make new connections as seen in photo (blue wires) Replace R59 and R65 with 0ohm.
Check bias current.
That's it.
de oz9ny, niels

sbitx-5w-pa.jpg

Re: Transverter Location #ubitx #2meters

 

¿ªÔÆÌåÓý

Aaron
? ? ?The antenna tuner goes in the line for the antenna that you want to tune ¡°after¡± the transverter.

Ed de: N7SNT?


On Sep 25, 2022, at 7:35 PM, Aaron K5ATG via groups.io <k5atg@...> wrote:

?No I have a 2 Meter beam.?
On the transverter the coax goes from the HF rig to the transverter. Then you got two antenna jacks on the transverter, one for the VHF antenna and one for the HF antenna. The jack labeled HF ANT goes to the HF antenna. Then jack labeled? VHF ANT goes to the 2-meter antenna.?
The question is should the external antenna tuner be put in line before or after the transverter or does it matter??

transverter rear.jpg
--
'72
Aaron K5ATG
Re: sBitx DE sold out

Mark Earnest
 

My finals now blow when attempting to set the bias, I¡¯m concerned I may have damaged something else as well. Is there anything in particular I should be checking?


--
KB3LYB
sBitx #077
Re: sBitx with ESP32 #sBitx #esp32

 

¿ªÔÆÌåÓý

Ashhar,

I respectfully disagree, the Raspberry Pi Zero 2 is now sold for anything between 12€ to 24€ (if available),? add to that the shipping costs and the cost of a small SD card.?
Agreed however, the Raspberry Pi Zero 2 is probably capable of running the entire sBITx software suite.?

73


Op 25/09/2022 om 19:05 schreef Ashhar Farhan:

Jean,
The Raspberry Zero 2 is actually cheaper than the Black Pill.?
It might be a good idea to design plugin boards to try out different CPUs.

On Sun, Sep 25, 2022, 8:42 PM jeanrenier2004 <jean.taeymans@...> wrote:

Stephen & Ramon,

Sorry to barge into your discussion, but since the last months I have been experimenting with exactly what your are proposing, I thought might forward some comments.

Nor the ESP32, nor the RP2040 are actually powerful enough to perform any serious DSP.? They can do some digital filters all right but not with the precision that is needed for any serious SSB demodulation (at least not with the limited knowledge of DSP that I have), I tried with both.?
Finally I got something working well using the STM32F411 (black pill), though this chip is only clocked at 100MHz it has a floating point coprocessor on board and this makes all the difference.?
The DSP chain is implemented using the Arduino IDE and the CMSIS DSP library and is textbook classic.? The receiving path starts from a rather modest 48ks/s signal for an IF of some 8kHz bandwidth centered around a 12kHz carrier.? It then features a 12kHz quadrature mixer, a pair of Hilbert +45¡ã / -45¡ã filters, a SSB demodulator and a main LPF, yielding an audio signal at the output.? The transmitting part does the reverse, audio in and a 12kHz SSB modulated carrier out.?
As the DSP process takes already about 2/3 of the CPU time, no spectrum display or waterfall was implemented.? AM and FM demodulation are not implemented yet, but are certainly feasible.? To control the radio (frequency, mode, ...) a simple CLI was implemented, a CAT interface (FT817 style) is working also.? Connecting a OLED/LCD for a GUI of sorts was also tried, but abandoned as the libraries for these do not live well together with the I2S routines (cracking noises every time the screen was updated). ? An additional controller for the GUI would not be too bad or cost too much.?

The hardware (see picture), is very much that of the sBITx (eternally indebted to Ashhar), including the WM8731A codec (which is indeed "finicky" as Ashhar puts it).? The board (100mm by 100mm) which contains the receiver part and the exciter part, is essentially an experimental platform and was developed in several phases, hence some lose wires, odd mounted components and the gluing of boards, including the actual black pill (about 8€, import from China).

This project is still very much work in progress (I am currently struggling with some harmonic distortion at the 12kHz carrier output), I am nevertheless willing to share the software and hardware design files with whoever is interested in pursuing this line of work.

73? Jean - on4jrt



Op 25/09/2022 om 11:59 schreef Stephen Farthing:
Ramon,?

I think this is a possibility. There is a series on YouTube of using an ESP32 as an SDR modulator demodulator. I don¡¯t have the link but if you search you should find it. Lots of maths and coding.?

73s Steve G0XAR
On Sun, 25 Sep 2022 at 11:52, <ramonlh@...> wrote:
Hello,
I wonder if it would be possible to do the signal processing with an ESP32 micro. The idea would be to take the "AUDIO-DEMOD" signal and inject it with "AUDIO-MOD", replacing the Raspberry process.
If it worked it could lead to a "compact and low cost sBitx". Radio control could be done with a modified Raduino32 and use another ESP32 for signal processing.
My knowledge and skills on FFT and C programming are limited but if anyone is interested we could work on it.
?
Ramon EA4GZI
Re: Double sided PCB for RF

 

I use the ground fill feature of Fritzing for all my boards.
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