Re: Working on my 2nd V2 sBitx
On Tue, Mar 18, 2025 at 10:44 AM, Gordon Gibby KX4Z wrote:
I have not yet checked the potential reduction in receiver birdies from the aluminum foil shielding of the display cable.
It does not reduce the number of receiving stations, but it significantly increases the sensitivity that can be adjusted with the sensitivity control, which is also visible in the waterfall.
In the unshielded state, it started to get noisy above 50, with shielding this level shifts to around 80.
?
--
Gyula HA3HZ
|
Re: Working on my 2nd V2 sBitx
Attached is a final document with a list of the reliability-improvements and photos of how I managed to put them in.? ?Amazingly, I didn't break anything!? ?It appears to work just fine afterwards.? ?I have one of the 64-bit setups working and thanks to some help, I can compile this also!? ?
?
- I have not yet checked the potential reduction in receiver birdies from the aluminum foil shielding of the display cable.
- I'm away from normal home and don't have a good 50-ohm dummy load so no reliable power output measurements so far, but appears to be at least as good as the previous V2 IRF520 replacement that I did.
?
?
IRF520? Infineon? ?biased for about 0.3Amp total idling current
3pf TVS diodes on gates instead of the previous huge zeners (which Ashhar says don't stop the problems)
MODE = CW? ?Power measured by Siglent scope and mathematically voltage -> 50 ohm power
Frequency? ? 100% drive output power? ? hw_settings.ini? ? Comment
3.5010? ? ? ? ? ? ? ?32W? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? .0037? ? ? ? ? ? ?Gets a little less power than on 40, similar setting to IRFZ24N
? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? my earlier notes suggest I got a little more power than this, with the IRFZ24N's
? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? and gate zeners, so the IRF520 may be a little inferior here.
?
7.010? ? ? ? ? ? ? ? ? 33.3? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ?.0028? ? ?
10.1? ? ? ? ? ? ? ? ? ? 22.6W? ? ? ? ? ? ? ? ? ? ? ? ? ? ? .0028? ? my notes indicate I was in the range of 21W with IRVZ24N & gate-zeners
14.01? ? ? ? ? ? ? ? ? 16W? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ?.0032? ? my notes here on IRFZ24N don't make sense
18.1? ? ? ? ? ? ? ? ? ? ?9.33? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ?.0061? ? ? ? ? ? ?? the gate circuit reactance issue here?
? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ?notes indicate I got 11-12W with IRVZ24N's
21.01? ? ? ? ? ? ? ? ? 16.6? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? .0054? ?notes indicate I could only get 15W with IRFZ24N & gate-zeners
24.9? ? ? ? ? ? ? ? ? ? ?12.3? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ?.0063? ?notes indicate I could only get 10W with IRFZ24N & gate-zeners
? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ?likely due to their huge capacitance
28.0? ? ? ? ? ? ? ? ? ? ?11.52W? ? ? ? ? ? ? ? ? ? ? ? ? ? .0063? ?notes indicate I could only get 8W with IRFZ24N & gate-zeners
? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? likely due to their huge capacitance
?
Without a dummy load, I made some initial measurements and adjusted the coefficients on the new unit and on several bands came up with very similar coefficients, suggesting that the circuitry and devices are performing reasonably similar.? ?I think I'm getting in the range of 40W on the two lowest bands, at around 12 watts on 10 meters.? ?These numbers are quite adequate for me!? ?I like having the additional robustness against excessive drive that the TVS diodes may bring, and the additional robustness against SWR-issues, that the 100V (drain-source limit) that the IRF520's give.? ?(Ashhar selected the IRF510 for the V3 with the same drain-source voltage capability).? ?Be careful to buy 520's from reputable sources and there are versions out there with inferior specifications.
?
73
Gordon KX4Z
?
|
Yes, Gerry, I agree.? ?I don't know the particulars of the not-yet-released zBitx, however, presuming it either has a "send relay output" (or equivalent) or one can be added, it should be a fine option for the exciter transceiver for a transverter (as I have recently tested using the sBitx V2 in such a role).
The electrically controlled transmit/receive switching appears to be important for satellite work (though I have no personal experience) because the "vox" type control just doesn't "hold in" with SSB speech (which I verified with one of the Ukranian-sourced transverters).? ?If the send output doesn't exist, it should be easily added as some of us have already done on the sBitx.
?
And you are right about gpredict.? Ashhar Farhan suggested this software, apparently using it himself for this purpose.? ?I downloaded it and installed it on an sBitx and it ran well once I used a display with enough pixels to be able to see the entire page (some of the dialog boxes have fixed dimensions and without being able to get to the buttons at the bottom, you couldn't get out of the choices).? ?I also found that the sBitx 32-bit firmware could be listed as a radio interface under "preferences" and perfectly accepted the calls to port 4532 from gpredict operating on the same device.? ?and obeyed the commands to track Doppler shift, without the need for rigctld (the function is provided right within sBitx).? ? This was quite nice!? ?gpredict allows you to enter the local oscillator of a (mixer-type) transverter.? ? Now not having the unit in hand I can't prove that all will fit and work acceptably on the zBitx but if there is space and speed, it should work.? ??
?
73
Gordon KX4Z
?
?
?
|
?
-----Ursprüngliche Nachricht-----
toggle quoted message
Show quoted text
From: Gerald Sherman via groups.io
Sent: Tuesday, March 18, 2025 3:49 AM
Subject: [BITX20] zBit thoughts
?
I know the zBit hasn't been delivered yet.? From what little firm
information we have, it looks as if this radio would make an excellent
unit as a tunable IF to work into a transverter for operation on
frequencies above 30 Mhz.? I won't be doing this with mine, but it's a
thought.? One thing I do want to do when I get mine is to install a
couple of PDF files that I have prepared as databases for DX work.?
Those of us who work the satellites might want to install GPREDICT.?
This is a tracking program, and it is available for Linux.? I don't
know
if it is available for the Pi, but it is for Intel/AMD CPUs.? These
thoughts might also be good for the sBit.
?
Gerry Sherman
?
Sent by the Windows 11 Thunderbird
?
?
?
?
?
|
I know the zBit hasn't been delivered yet.? From what little firm information we have, it looks as if this radio would make an excellent unit as a tunable IF to work into a transverter for operation on frequencies above 30 Mhz.? I won't be doing this with mine, but it's a thought.? One thing I do want to do when I get mine is to install a couple of PDF files that I have prepared as databases for DX work.? Those of us who work the satellites might want to install GPREDICT.? This is a tracking program, and it is available for Linux.? I don't know if it is available for the Pi, but it is for Intel/AMD CPUs.? These thoughts might also be good for the sBit.
Gerry Sherman
Sent by the Windows 11 Thunderbird
|
Re: zBitx alternative board...
The
zBitx has not even been delivered yet... but there is already discussion and
grumbling in advance, even though no one has any practical experience with the
zBitx. Excuse me... I find that unbearable.
|
Re: zBitx alternative board...
From: Ken N2VIP
Sent: Sunday, March 16, 2025 10:47 PM
Subject: Re: [BITX20] zBitx alternative board...
?
It is fascinating watching hams solve problems/improve a radio that hasn't
even shipped yet, let alone demonstrate problems that need addressing.
?
A quick search leads me to believe that FreeDV works fine on an RPi 3B+,
which is the same processor in the RPi Zero 2 W board, but the Zero 2 W has half
the RAM - the question is, does FreeDV require much RAM?
?
Ken, N2VIP
|
Re: uBITX v6 Alignment Question
Hi Evan and Gary. Yes, you were right, that was it. So for now it appears the little beast is working as it should. It will be on the air tomorrow to shake out any cobwebs. All is looking OK - for now. Thanks for all your assistance. 73, Richard AG5M
On Monday, March 17, 2025 at 02:05:28 PM PDT, Evan Hand via groups.io <elhandjr@...> wrote:
Hi Richard, ? The change does not take effect unless you adjust the frequency.? Try the experiment with a click-up and click-down in frequency after changing from USB to LSB and vice versa. ? 73 Evan AC9TU ?
|
toggle quoted message
Show quoted text
-------- Original message --------
From: "Evan Hand via groups.io" <elhandjr@...>
Date: 3/17/25 5:02 PM (GMT-05:00)
Subject: Re: [BITX20] reviving my sbitx v3
Michael,
?
I believe these are the parts:
?
|
|
CDSOD323-T08CCT-ND
TVS DIODE 8VWM 18.5VC SOD323
|
?
?
?
?
?
?
I found them on Mouser and Digi-Key.
?
73
Evan
AC9TU
-- Mike - K8MCB?
|
Re: The sBitx disk image - too big for certain (theoretically) 32GB SD cards
Use this ... https://github.com/Drewsif/PiShrink
--
Pete VK3PYE
|
Re: uBITX v6 Alignment Question
Richard,
If I remember correctly, the stock firmware requires you to change frequency before it switches to the new side band selection.?
-Gary
|
Re: uBITX v6 Alignment Question
Hi Richard,
?
The change does not take effect unless you adjust the frequency.? Try the experiment with a click-up and click-down in frequency after changing from USB to LSB and vice versa.
?
73
Evan
AC9TU
?
|
Michael,
?
I believe these are the parts:
?
|
|
CDSOD323-T08CCT-ND
TVS DIODE 8VWM 18.5VC SOD323
|
?
?
?
?
?
?
I found them on Mouser and Digi-Key.
?
73
Evan
AC9TU
|
uBITX v6 Alignment Question
Now that the audio issue has been fixed, I proceeded with alignment of BFO and Frequency.? For the most part, after viewing multiple videos, I did the alignment mostly by ear.? It sounds good, and frequency appears to be spot on. On air reports are fine, both SSB and CW.
?
However, if I am on the Noon-Time-Net (NTN) 7,284 LSB, I notice if I go to USB there is no change in the audio.? Sounds just as clear as when in LSB.? If I use CW to check into the NTN, dial set at 7,283.30, same thing.? No change in the audio on either USB or LSB setting. ?Is that normal for this radio?? No other radio I own acts like this, thus the question.? Thanks, 73 Richard AG5M
|
Re: Adding external relay control two V2/V3
On Mon, Mar 17, 2025 at 05:02 PM, Gordon Gibby KX4Z wrote:
Now I just need to learn how to compile the new version. Does anyone know the proper way to do that?
You can read the description if you don't remember the process. I document every modification step by step, so I can always look back at how I did it.
I see that you solved the installation. Always enter the given directory where you want to do the installation.
If you missed following the development, it is worth loading the sBITX-Toolbox v3.01, because there are many new things in it.
In sbitx v4.4, a lower driver level is enough for the same output power. The thing only appeared because I use it with constant voltage and current limit.
--
Gyula HA3HZ
|
Re: Compiling sBitx in 64 bit image
Well, maybe I was inside the source directory when I tried it before? In the sBitx ?directory it works perfectly. ? Thanks, Evan!!
Gordon kx4z?
toggle quoted message
Show quoted text
On Mar 17, 2025, at 14:07, Gordon Gibby KX4Z via groups.io <docvacuumtubes@...> wrote:
? I get the directions mixed up. I think I did that, but I’ll try it again when I get back home. On Mar 17, 2025, at 13:45, Evan Hand via groups.io <elhandjr@...> wrote:
? Gordon,
Did you cd to the sbitx directory?
Also, the command is ./build sbitx.
?
73
Evan
AC9TU
|
Re: Compiling sBitx in 64 bit image
I get the directions mixed up. I think I did that, but I’ll try it again when I get back home.
toggle quoted message
Show quoted text
On Mar 17, 2025, at 13:45, Evan Hand via groups.io <elhandjr@...> wrote:
? Gordon,
Did you cd to the sbitx directory?
Also, the command is ./build sbitx.
?
73
Evan
AC9TU
|
Re: Compiling sBitx in 64 bit image
Gordon,
Did you cd to the sbitx directory?
Also, the command is ./build sbitx.
?
73
Evan
AC9TU
|
Compiling sBitx in 64 bit image
OK, Mr. clueless here.
I tried the .\build sbitx On the new image with 64 bit operating system and it didn’t work. Something about missing make file. I know I could probably figure this out, but somebody probably knows the answer right off the bat.
?
What do we have to do in order I’ll the new 64 bit version on the 64 bit image that was so kindly provide provided???
?
I must be missing something. ?Now that I have it running, and I have upgraded the hardware on my 2nd sBitx, I want to start tinkering with software things again!!
(Full report on the hardware upgrade coming soon. It went way better than expected. I found easier ways to do things.)?
?
?
gordon kx4z?
?
|
Re: Working on my 2nd V2 sBitx
Thanks, Gordon,
I have a working V2 and have started doing upgrades. I appreciate all your information on this.
George VY1GP
|
HA3HZ
Jens/HB9JOI
Richard AG5M
Peter VK3PYE