|
Finally took the plunge and bought one of those Ukranian 2m/70cm Transverters -- with the fancy MOSFET so it is supposed to do 10W on 2m.? ?
Eventual goal is to learn something about the linear translation satellites.
?
Got it all connected up this afternoon.? ? The attenuator inside the unit is way off from what they said it would be -- I have the sBitx at about 19% power level to avoid overdriving the transverter.? ? I can't find my "normal" sBitx mic so having to use a CB amplified mic and a rube-goldberg set of connections.... but it works!!
?
Made first 2m SSB and CW contact EVER in my life to friend who has a superb VHF / UHF setup about 11 miles away -- this with a homebrew 3 element beam made years ago from welding wire, laying between bannister and chair.? ?The sBitx worked perfectly.? ? The transverter only has "vox" and wouldn't stay "in" during SSB voice -- but others have added a ptt connection before and I should be able to also, since I already have a "send" output on my sBitx.? ?
?
The eventual goal is to try SATELLITES.? ? But I have to crawl before I walk.....
?
Gordon KX4Z??
?
?
?
|
I was able to get the top off, find the device that controls the relay, and add a connection (through a 100 ohm resistor) to allow my sBitx send output (that I added) to activate the T/R system of the transverter.? ?That made it FAR easier to do SSB; the transverter STAYS IN TRANSMIT rather than jumping in and out.
?
My experience with the gain/attenuation is exacctly that the reviewer on eHam.net found -- with the original setting, only 0.4-0.8w was enough to max out the 2m output.? ?BE CAREFUL -- do not apply 5W like the instruction sheet says.? ? I haven't tried the 70cm side yet, but the eHam reviewer said its gain was normal.? ?
?
Easily able to have a SSB contact with another local ham on 2 meters now using the sBitx as the 10m exciter.? ? Running now with a 31% drive after adjusting the attenuation in the transverter a bit.? ? ?This should be about 0.9W drive.? ?
?
Working great!? I have to give a talk about the sBitx updates in a week, so this is very timely.? ?
?
Gordon KX4Z
?
?
|
Sounds fun, I'll be listening for you on the "Birds" RS-44 is pretty easy to work ??
|
Wow! BITX for working linear satellites! That is really cool.
Has anyone thought of FM modules for BITX?
73 Jon, VU2JO
On Sat, Feb 15, 2025 at 9:29?PM Doug Backer via <dougbacker= [email protected]> wrote: Sounds fun, I'll be listening for you on the "Birds" RS-44 is pretty easy to work ??
|
I would love to see an FM mod. For now, I am busy figuring out how to pack transverters for 2m/440 into my custom sbitx box.
K8MCB
toggle quoted message
Show quoted text
-------- Original message --------
From: "Jon via groups.io" <vu2jo0@...>
Date: 2/15/25 11:05 AM (GMT-05:00)
Subject: Re: [BITX20] sBitx --> Transverter for 2m/70cm SSB/CW
Wow! BITX for working linear satellites!
That is really cool.
Has anyone thought of FM modules for BITX?
73
Jon, VU2JO
On Sat, Feb 15, 2025 at 9:29?PM Doug Backer via
<dougbacker= [email protected]> wrote:
Sounds fun, I'll be listening for you on the "Birds" RS-44 is pretty easy to work ??
-- Mike - K8MCB?
|
what about an upmixer from 70 cm to 13cm and use it for qo100 (if
you are in the footprint) and a downmixer from 740 megs down to 2m
(and then down to shortwave)
just thinking
dg9bfc sigi
Am 15.02.2025 um 17:05 schrieb Jon via
groups.io:
toggle quoted message
Show quoted text
Wow! BITX for working linear satellites!
That is really cool.
Has anyone thought of FM modules for BITX?
73
Jon, VU2JO
On Sat, Feb 15, 2025 at
9:29?PM Doug Backer via <dougbacker= [email protected]>
wrote:
Sounds fun, I'll be listening for you on the "Birds"
RS-44 is pretty easy to work ??
|
Oh! BITX to move from Low Earth Orbit to Geostationary Orbit. Not sure whether VU2ESE would have thought of it, being a pioneer in this region for amateur LEO launch.
73 Jon, VU2JO On Sun, Feb 16, 2025 at 12:55?AM Siegfried Jackstien via <siegfried.jackstien= [email protected]> wrote:
what about an upmixer from 70 cm to 13cm and use it for qo100 (if
you are in the footprint) and a downmixer from 740 megs down to 2m
(and then down to shortwave)
just thinking
dg9bfc sigi
Am 15.02.2025 um 17:05 schrieb Jon via
:
Wow! BITX for working linear satellites!
That is really cool.
Has anyone thought of FM modules for BITX?
73
Jon, VU2JO
On Sat, Feb 15, 2025 at
9:29?PM Doug Backer via <dougbacker= [email protected]>
wrote:
Sounds fun, I'll be listening for you on the "Birds"
RS-44 is pretty easy to work ??
|
One of our local "satellite gurus" Ron Lewis KN4ZUJ has clued me into the CSN SAT-TRACKER device that has the ability to simultaneously control Yaesu Rotators to track satellites, and send CAT commands over CI-V (open collector bidirectional) to very high-end ICOM transceivers. to adjust the RECEIVER frequency for the doppler shift (I gather people leave their transmitter fixed -- but I'm very new at this).
?
I had difficulty finding public domain solutions that did both these functions.? The solutions that were being built in the 2009-2010 era seemed to do one or the other and ground to a halt.
?
The CSN SAT TRACKER produces open collector output (to control high-end ICOM VHf/UHF radios).? ?I think my UART input? (see: /g/BITX20/wiki/36015 )? ICOM-emulator raspberry pi simple program (see: /g/BITX20/wiki/36021 ) could read those CAT commands from the SAT-TRACKER and then perform the proper translation to the ten-meter band where the "receiver" portion of a full-duplex dual-sBitx/dual-transverter system were connected.? ? That would then allow for the proper adjustment of receiver frequency to account for the doppler shift; while the SAT TRACKER simultaneously control the az-el rotators to point at the satellite. ?
So that may be a viable set of steps.? ?Today I was able to drive 2 hours and pick up some amazing aluminum tower components, and 17-foot long VHF/UHF yagis.? ?I don't think we need THAT for this project; a much simpler set of antennas should do.? ?We have some Yaesu rotators.? ? This isn't going to happy quickly, but with the progress I made this weekend getting the transverter working, verifying frequency accuracy, adding real TX/RX control, this may work eventually.
?
Gordon KX4Z
?
?
?
|
You can install gpredict on sbitx!
On Sun, Feb 16, 2025, 8:20 AM Gordon Gibby KX4Z via <docvacuumtubes= [email protected]> wrote: One of our local "satellite gurus" Ron Lewis KN4ZUJ has clued me into the CSN SAT-TRACKER device that has the ability to simultaneously control Yaesu Rotators to track satellites, and send CAT commands over CI-V (open collector bidirectional) to very high-end ICOM transceivers. to adjust the RECEIVER frequency for the doppler shift (I gather people leave their transmitter fixed -- but I'm very new at this).
?
I had difficulty finding public domain solutions that did both these functions.? The solutions that were being built in the 2009-2010 era seemed to do one or the other and ground to a halt.
?
The CSN SAT TRACKER produces open collector output (to control high-end ICOM VHf/UHF radios).? ?I think my UART input? (see: /g/BITX20/wiki/36015 )? ICOM-emulator raspberry pi simple program (see: /g/BITX20/wiki/36021 ) could read those CAT commands from the SAT-TRACKER and then perform the proper translation to the ten-meter band where the "receiver" portion of a full-duplex dual-sBitx/dual-transverter system were connected.? ? That would then allow for the proper adjustment of receiver frequency to account for the doppler shift; while the SAT TRACKER simultaneously control the az-el rotators to point at the satellite. ?
So that may be a viable set of steps.? ?Today I was able to drive 2 hours and pick up some amazing aluminum tower components, and 17-foot long VHF/UHF yagis.? ?I don't think we need THAT for this project; a much simpler set of antennas should do.? ?We have some Yaesu rotators.? ? This isn't going to happy quickly, but with the progress I made this weekend getting the transverter working, verifying frequency accuracy, adding real TX/RX control, this may work eventually.
?
Gordon KX4Z
?
?
?
|
Thanks, Ashhar! ?Beginning to read up on how to use that. ?
toggle quoted message
Show quoted text
On Feb 16, 2025, at 00:17, Ashhar Farhan via groups.io <farhanbox@...> wrote:
? You can install gpredict on sbitx!
On Sun, Feb 16, 2025, 8:20 AM Gordon Gibby KX4Z via <docvacuumtubes= [email protected]> wrote: One of our local "satellite gurus" Ron Lewis KN4ZUJ has clued me into the CSN SAT-TRACKER device that has the ability to simultaneously control Yaesu Rotators to track satellites, and send CAT commands over CI-V (open collector bidirectional) to very high-end ICOM transceivers. to adjust the RECEIVER frequency for the doppler shift (I gather people leave their transmitter fixed -- but I'm very new at this).
?
I had difficulty finding public domain solutions that did both these functions.? The solutions that were being built in the 2009-2010 era seemed to do one or the other and ground to a halt.
?
The CSN SAT TRACKER produces open collector output (to control high-end ICOM VHf/UHF radios).? ?I think my UART input? (see: /g/BITX20/wiki/36015 )? ICOM-emulator raspberry pi simple program (see: /g/BITX20/wiki/36021 ) could read those CAT commands from the SAT-TRACKER and then perform the proper translation to the ten-meter band where the "receiver" portion of a full-duplex dual-sBitx/dual-transverter system were connected.? ? That would then allow for the proper adjustment of receiver frequency to account for the doppler shift; while the SAT TRACKER simultaneously control the az-el rotators to point at the satellite. ?
So that may be a viable set of steps.? ?Today I was able to drive 2 hours and pick up some amazing aluminum tower components, and 17-foot long VHF/UHF yagis.? ?I don't think we need THAT for this project; a much simpler set of antennas should do.? ?We have some Yaesu rotators.? ? This isn't going to happy quickly, but with the progress I made this weekend getting the transverter working, verifying frequency accuracy, adding real TX/RX control, this may work eventually.
?
Gordon KX4Z
?
?
?
|
?
Ashhar’s ?tip has been very productive.
?
?
a German fellow created some interface hardware between the software rotctld (which puts out serial ASCII characters to control rotators) an actual rotator, such as the yaesu’s, which we have:?
?
?
?
(Vibro Plex is the US/candidate distributor for this gear)?
so with those simple pieces of equipment, we have the ability to control 2 rotators.
?
and with basically free software, it looks like we can control the Doppler shift and these rotators. We may need to do some programming to deal with the frequency translation, but the software should be available in source form
?
|
So for the very first time, I have gotten gpredict to control the frequency of a radio, auto-adjusting for Doppler shift.? ?Didn't cost me a penny!
?
I should have done this with the sBitx (which has NET rigctld responsiveness, rig "2" in rigctl-speak)? -- instead I thought (wrongly) it would be easier to learn by starting with a Windows Laptop and an ICOM 7300.? ?The 7300 does NOT have NET rigctl responsiveness.? ? Instead, I had to wade through all the learning to install a rigctld daemon on the laptop.? First I practiced with the command-line control program rigctl.? ?You get both of these when you download a hamlib installation system.? ?I had to learn the syntax to get rigctld installed to work with my Icom 7300 on COM3:
?
rigctld -m 3073 -r COM3
?
(the Icom is # 3073 in their long list....but you don't need this with the sBitx because it has NET responsiveness somewhere in the code.? This may not be the right way to explain that, but I think you get what I mean.? ?Gpredict on the default port is likely to directly immediately control the sBitx)?
?
Then I got that radio installed in gpredict....but it took me a long time to discover the icon at the far RIGHT of the menu bar where you actually direct the system to USE the radio and "track" the doppler shift.? ? You can specify the local oscillator of the transverter.? ?I cheated by telling the system I lived in Canada so I could simulat access to a satellite immediately, rather than having to wait wait wait for another pass -- and by clicking "track" (I don't fully understand all of that yet) I was rewarded by having the ICOM 7300 slowly adjust automagically for doppler shift as gpredict computed and corrected.
?
HOORAY!!? ? ? ?
?
This is just one step in a huge line of things I think I need to conquer, but according to some of the experts, this can be done with simple yagis and rotator control, because a lot of the satellites have circular polarization already.? ? ?Apparently you need some POWER which I only have 5-10 watts worth of so far, but hey, I'm learning!? ? ?Next step will be to get on the sBitx and repeat all of this with it in the linux world.? ?Having now figured out rigctl, I think rotator control (rotcld) will be very similar, and the available commercial package that Vibroplex sells from the european ham who figured it out, will make that much simpler for me.? ? Here is a very simple article explaining how easily one can start with antennas:
?
?
?
?
Gordon KX4Z
?
|
Let me congratulate you first for the excellent job. A slight doubt about this statement "because a lot of the satellites have circular polarization already"
My impression was that most satellites have just linearly polarized antennas. But the orientation changes continuously as the satellite tumbles and spins in orbit. If you use circularly polarized antennas for reception, the chance of drop in signal due to cross polarization is lesser. If we use linearly polarized antennas, that is more.?
As a disclaimer, I use only linearly polarized antennas for LEO satellite operations, just because I do not have the luxury of a circularly polarized antenna and even a rotator!
|
Jon, I’m not sure about it either. I found it in a training document on the AMSAT website. I’m not sure it’s still true?
?
I don’t have firsthand knowledge
?
gordon?
|
Gordon,
My statement is also from AMSAT material!
Do continue your excellent work and keep us posted.?
After having left radio homebrewing over three decades back, I am?watching with great interest the ongoing work with BITX. When I came back to ham radio in 2023, I wanted very much to start with BITX. But it was not available here then and I bought?IC 2730A?for LEO satellites and FT-710 for HF.
73
Jon, VU2JO On Mon, Feb 17, 2025 at 7:43?PM Gordon Gibby KX4Z via <docvacuumtubes= [email protected]> wrote:
Jon, I’m not sure about it either. I found it in a training document on the AMSAT website. I’m not sure it’s still true?
?
I don’t have firsthand knowledge
?
gordon?
|
Well, after trying quite unsuccessfully to download and install (compile) gpredict, with lots of complaints that my (ancient) setup is out of date and missing this and that......I discovered it is already available and installed and accessible under the HAM tab on the sBitx menu!? ?DUH!
But the screen won't allow me to get to the bottom of some of the configuration dialogs, to click "add" or "OK" or such, so I'm stopped until an adapter arrives so I might be able to move this to a monitor screen with more pixels.? ?But it looks like what I need, is already there!
I couldn't see any other way to get around the fixed-size of some of the gpredict windows......maybe there is a solution I just don't know about.? ?Adapter cable should arrive tomorrow
Gordon KX4Z
Gordon,
My statement is also from AMSAT material!
Do continue your excellent work and keep us posted.?
After having left radio homebrewing over three decades back, I am?watching with great interest the ongoing work with BITX. When I came back to ham radio in 2023, I wanted very much to start with BITX. But it was not available here then and I bought?IC 2730A?for LEO satellites and FT-710 for HF.
73
Jon, VU2JO
On Mon, Feb 17, 2025 at 7:43?PM Gordon Gibby KX4Z via <docvacuumtubes= [email protected]> wrote: Jon, I’m not sure about it either. I found it in a training document on the AMSAT website. I’m not sure it’s still true?
?
I don’t have firsthand knowledge
?
gordon?
|
From: Ashhar Farhan via groups.io
Sent: Sunday, February 16, 2025 6:17 AM
Subject: Re: [BITX20] sBitx --> Transverter for 2m/70cm
SSB/CW
?
You can install gpredict on sbitx!
On Sun, Feb 16, 2025, 8:20 AM Gordon Gibby KX4Z
via
<docvacuumtubes@...> wrote:
One of our local "satellite gurus" Ron Lewis KN4ZUJ has clued me into the
CSN SAT-TRACKER device that has the ability to simultaneously control Yaesu
Rotators to track satellites, and send CAT commands over CI-V (open collector
bidirectional) to very high-end ICOM transceivers. to adjust the RECEIVER
frequency for the doppler shift (I gather people leave their transmitter fixed
-- but I'm very new at this).
?
I had difficulty finding public domain solutions that did both these
functions.? The solutions that were being built in the 2009-2010 era
seemed to do one or the other and ground to a halt.
?
The CSN SAT TRACKER produces open collector output (to control high-end
ICOM VHf/UHF radios).?? I think my UART input? (see: /g/BITX20/wiki/36015 )? ICOM-emulator
raspberry pi simple program (see: /g/BITX20/wiki/36021 ) could read those CAT
commands from the SAT-TRACKER and then perform the proper translation to the
ten-meter band where the "receiver" portion of a full-duplex
dual-sBitx/dual-transverter system were connected.??? That
would then allow for the proper adjustment of receiver frequency to account
for the doppler shift; while the SAT TRACKER simultaneously control the az-el
rotators to point at the satellite. ?
So that may be a viable set of steps.?? Today I was able to
drive 2 hours and pick up some amazing aluminum tower components, and 17-foot
long VHF/UHF yagis.?? I don't think we need THAT for this project; a
much simpler set of antennas should do.?? We have some Yaesu
rotators.??? This isn't going to happy quickly, but with the
progress I made this weekend getting the transverter working, verifying
frequency accuracy, adding real TX/RX control, this may work eventually.
?
Gordon KX4Z
?
?
?
|
On Mon, Feb 17, 2025 at 12:02 PM, Jens/HB9JOI wrote:
You can install gpredict on sbitx
Mostly off topic but on the off chance it helps someone, I built an earlier version of this a few years ago ? (be sure to check out the rest of their site) it was a relatively inexpensive way to figure out using gpredict with a rotator.? I only used it to track the ISS with an Arrow antenna.? I never did anything more than chase SSTV images.? I connected the Arrow to a cheap Baofeng and held my phone close enough running robot36 to convert screeching to pictures of smiling astronauts.
|
Doug W, THANKS!? ?I had seen some of their work before, but your comment led me to go back there again and study it more -- and they made a huge point about how much NOISE they had from the raspberry pi's!!? ?The more computers, the more noise, and lots of work to deal with it.
?
?
I've never had towers/ beams / rotators before.? ?This is all new to me.
It looks almost like highway robbery:
?
First you have to have some gizmo that products corrections and tower controller calculations -- I saw one for about $300.? ?These product a structured language of commands.?
?
THEN you take that output and it goes to some kind of computer interface thing -- I saw some of THOSE were in the $500 range years back? That produces another structured output (why?) and it goes then to an otherwise manually-controlled rotator box (another $100) that then goes to one or two $$$$$$ rotators if you are going to swing any sizeable antennas and not strip gears right and left.
?
WHAT A RACKET!!? ?
?
I have observed that the sBitx can produce?
a)? free gpredict sends tcp/ip commands over internal directly into sBitx to do CAT control of Doppler correction [haven't been able to prove that but have emulated it on an Icom 7300 and it worked)? ?$0 cost
b)? free grpredict can send tcp/ip commands port (4533) to same processor rotctld which can output USB from the rapsberry pi to go to $140 device that can directly control boxes or relays $28? for Yaesu and other rotators -- 2 axis even! ?
?
We already have 2-3 rotators and we are starting to accumulate yagis (a fellow gave us two 17-foot yagis.....I think they are WAY overkill so we won't use the full length.
?
This may never get finished but at least I'm learning and haven't had to spend much $$$$ yet.....
?
Gordon KX4Z
?
|
On Mon, Feb 17, 2025 at 05:30 PM, Gordon Gibby KX4Z wrote:
I've never had towers/ beams / rotators before.? ?This is all new to me.
------------------------
?
?
My only experience is building that sarcnet project.? One of these days I want to build something more robust but the best (and possibly worst) thing about this hobby of ours is I often find something else that catches my eye that pushes me down the next rabbit hole.? W8TEE and W6DQ's Arduino Projects book has a rotator controller project too.? They do a good job of actually explaining why and how everything works whereas the sarcnet project is mostly just plugging together modules.
|
Jens/HB9JOI