POTA a perspective, many activations with zBitx. ?Usually get five contacts in before taking a break for heat dissipation. ?My fingers are my gauge. Running the radio at 75% drive usually change in a second set of batteries after the first drops to 6 volts. ?Typically one and a half pairs of batteries per outing, the second set is usually still 7+ volts at the end. Did a five park outing on six batteries. ?A lot less gear than using my Sbitx. Tim - W1WCI Sent from me and my iPad
toggle quoted message
Show quoted text
On May 23, 2025, at 9:20?AM, Dave, N1AI via groups.io <n1ai@...> wrote:
? On Thu, May 22, 2025 at 10:55 PM, Jay Bremner wrote:
So if we are talking about the HRCC video and how his radio was resetting, he posted a follow up video and admitted that he used a 1A power supply. When he connected a 3.5A power supply, problem solved.
?
I wasn't talking about that situation, but you might be inadvertently pointing out why it is not the perfect POTA/SOTA solution: should you have to supply 3.5A at 7.2V = 25W to a POTA radio to make 5W output? ?How many watt-hours of batteries are you going to have to bring to that park/summit to have a decent outing?? And if you do so, isn't a lot of that power that isn't going out the antenna producing a lot of heat inside a small package?? ?At some point, isn't it a better idea to address the root cause of the problem instead of applying work-arounds?
I agree just having a solid aluminum baseplate as a heatsink with no mechanical ventilation could be an issue, I ordered a thermoelectric cooling fan that will attach to the back of the radio and that does add about 2 ounces. Despite these issues, I don¡¯t mind tinkering with radios and think it will be a fun experiment.?
?
? I can always take my G90 out if it doesn¡¯t work out. ?
?
The person who started this thread said that price was important to them which is part of why I chose to respond.??
?
Like I said, the review I posted is really balanced.? It points out the good and the bad and everything in between.? ?I admire Farhan's motivations and innovations.? ?I just think people should spend some time understanding what they are buying, especially if $200 is a meaningful part of their hobby budget.??
?
--
Regards,
Dave, N1AI
|
Re: Homebrew satellite control system that can run on sBitx
Would love to see some close-ups of your elevation setup with the linear actuator! What material did you use for the elements on your yagis? I¡¯m on the same journey right now.? 73 de W0ZF? On Fri, May 23, 2025 at 5:10?AM Gordon Gibby KX4Z via <docvacuumtubes= [email protected]> wrote:
I have now gotten an elevation system working very well using a linear actuator (12V) from Amazon.? ?Also created crossed yagi's to allow for circular polarization.? ? Using "J" half-folded dipole driven elements has turned out very well.? ? The impedances of these driven elements wasn't as large as I had expected (they are dragged downward in impedance by the influence of the nearby reflector and director).? ?However a very fortunate outcome was that the impedance of putting each crossed yagi in parallel with the other resulted in nice combined impedance.? ?I chose to use short feedlines that (corrected for velocity factor) were 1/2 wavelength, for the purpose of allowing me to use a nanoVNA to try and estimate the actual feed point impedance.? ?It worked!
?
Putting the yagis in parallel using a BNC T-connector resulted in an almost perfect SWR on my 70cm set and tolerable on the 2meter set.? ??
?
Here is a photo of the final antenna, with the booms and yagi's now implemented in standard 3/4 inch Schedule 40 PVC from Home Depot:
?
?
I'm still very very new at all of this, but I have now been able send and receive AX.25 (packet) to the ISS very easily on 2 meters.? ?This is an APRS digipeater, so acts a little differently than normal digipeaters I'm familiar with.? ? ?I'm still working on figuring out the best software with which to approach it -- there are LOTS of users so it is a big crowded!
?
Working my way back up to attempting the LINEAR satellites.? ?In the meantime, I have now worked out how to control the rotators remotely over WIFI using a raspberry pi to run the rotctld.? ?That will be for another post here.
?
So far the Yagi's seem to be working amazingly well for the homebrew way that i built them!? (the box on the base is just for stability weighting)
?
Gordon KX4Z
?
|
Re: Up and Running Fully Portable
Having fun with mine as well.?? I did not bother to try the OTG
adapter at all, but I've been doing stuff with various RPis for a
while so I had several of the necessary USB and mini HDMI adapters
around.
For my keyboard and mouse I used a small multi port USB hub and
that's working fine.??? I do like the idea of a bluetooth keyboard
though, and one with a trackball would be awesome.? That would
keep from putting too much regular stress on that mini USB
connector.? Mind sharing which keyboard/trackball you're using?
As for batteries, I got a four pack of the 18650s and a charger,
but you can kill a set of those pretty quickly on an FT8 operating
session, so I have a 12.5-7V dc to dc converter on the way.? As
long as noise isn't an issue, I'll probably use that and run it
off my battery box.? I'm also an RC guy, so I thought I might make
an adapter for a Lipo 2S pack as well.? I have several of those
available.
73, Steve KF8KI
On 5/23/2025 12:11 AM, Gwen Patton via
groups.io wrote:
toggle quoted message
Show quoted text
Yeah, I ran
into the same issue with that OTG adapter. I think it's not
so much an OTG adapter as a crisp, tasty waffle. I had one
around, and, like you, got my keyboard and mouse working.
Then I paired a handheld keyboard with a trackpad built in,
and I'll likely use that. I think I'm going to make a
technical bag to go along with the radio's go-bag, one with
an HDMI cable, a 14-inch portable screen, and a better
bluetooth keyboard I have that's got a built in trackball.
Each of those things is bigger than the repurposed
photographer's bag I'm using for the radio and its immediate
gear. I need to get the radio out and update the firmware
and UI anyway, so I'll do the pairing for the new keyboard
while I have it out.
I got an
8-pack of 18650 batteries and a USB-C powered 4-place
charger that has been a real workhorse. I like that it
doesn't need a mains plug. I'm about halfway through
assembly of a 5-band link dipole. Once I get the basic build
put together, I'll run it up a telescoping mast and tune it
up. Then I'll crimp on bullet lugs to make connecting the
links easy, and it'll be in service. I've got a 3-band link
dipole already, but I need to replace the connectors in the
links, and it doesn't have my favorite bands in it. Besides,
I made the new one out of Kev-Flex. Durable.
-=-=-=-=-=-=-=-=-
73,
Gwen, NG3P
BitXers,
??? Been playing with and
learning my new zBitx and I am having a blast.? I have
made a couple CW contacts almost immediately after
receiving my unit.? I had a couple unexpected hiccups in
that I wasn't prepared for the "Mini-HDMI".? The other
was the USB-OTG adapter that came with it was bad.?
Fortunately I had another stuffed in a drawer and
decided to try it.? Keyboard came right up and I was
able to get the unit up in Host mode.? I paired up my
bluetooth keyboard so I no longer have to deal with the
USB port for that.
I am running a portable
16inch (USB powered) monitor along with the wireless
keyboard and can run the rig on either 18650 batteries
or my Bioenno 1212Ah based battery box.? Got the clock
sync'd up and started up FT8 on 20m and made my first
contact within in a minute....
Great start so far.? It's
not a KX2 but this little unit is a lot of fun
especially with all the build in apps which I still need
to play with.
Attached is a couple of
photos.
--
"POWER, WE DON'T NEED NO STICKIN' POWER" - EVERY KX2 OWNER
Always respect the airwaves,
73 de KI7PBR, Gary
|
On Thu, May 22, 2025 at 10:55 PM, Jay Bremner wrote:
So if we are talking about the HRCC video and how his radio was resetting, he posted a follow up video and admitted that he used a 1A power supply. When he connected a 3.5A power supply, problem solved.
?
I wasn't talking about that situation, but you might be inadvertently pointing out why it is not the perfect POTA/SOTA solution: should you have to supply 3.5A at 7.2V = 25W to a POTA radio to make 5W output? ?How many watt-hours of batteries are you going to have to bring to that park/summit to have a decent outing?? And if you do so, isn't a lot of that power that isn't going out the antenna producing a lot of heat inside a small package?? ?At some point, isn't it a better idea to address the root cause of the problem instead of applying work-arounds?
I agree just having a solid aluminum baseplate as a heatsink with no mechanical ventilation could be an issue, I ordered a thermoelectric cooling fan that will attach to the back of the radio and that does add about 2 ounces. Despite these issues, I don¡¯t mind tinkering with radios and think it will be a fun experiment.?
?
? I can always take my G90 out if it doesn¡¯t work out. ?
?
The person who started this thread said that price was important to them which is part of why I chose to respond.??
?
Like I said, the review I posted is really balanced.? It points out the good and the bad and everything in between.? ?I admire Farhan's motivations and innovations.? ?I just think people should spend some time understanding what they are buying, especially if $200 is a meaningful part of their hobby budget.??
?
--
Regards,
Dave, N1AI
|
Re: Unreliable WIFI on zBitx?
Hey Jody,
When you were running RealVNC in your configuration, did you also
have an external display hooked up?? Or were you just connected to
the device with RealVNC?
When I was running yesterday I had both RealVNC AND a monitor,
keyboard and mouse.?? I disconnected everything last night to sit
on the porch and run some FT8 and JUST connected to it with
RealVNC this morning to export the FT8 logs.?? I immediately
noticed that the resolution on the display is different.? With an
HDMI monitor hooked up, the desktop was the size of the monitor.?
This morning, the desktop appears to be just about the size of the
built in display.?? I'm having some display issues showing all of
sBitx, but that's a different issue.
What's notable is that in this configuration, RealVNC seems much
more stable than it was with the monitor connected and thus much
higher display resolution.
Thanks!
Steve KF8KI
On 5/22/2025 1:31 PM, Jody - K3JZD via
groups.io wrote:
toggle quoted message
Show quoted text
I have run SSH and RealVNC for hours at a time while trying
out things.? But I am either 5 feet away from my WiFi Router or
about 30 feet away.? ?I have not experienced any unexpected
disconnects with either connection.? But I have only been using
CW into a dummy load.? So, maybe my results are not typical.
?
72,
Jody - K3JZD.??
|
Re: Homebrew satellite control system that can run on sBitx
Beautiful work Gordon! Very impressive.
73
toggle quoted message
Show quoted text
On May 23, 2025, at 6:10?AM, Gordon Gibby KX4Z via groups.io <docvacuumtubes@...> wrote:
? I have now gotten an elevation system working very well using a linear actuator (12V) from Amazon.? ?Also created crossed yagi's to allow for circular polarization.? ? Using "J" half-folded dipole driven elements has turned out very well.? ? The impedances of these driven elements wasn't as large as I had expected (they are dragged downward in impedance by the influence of the nearby reflector and director).? ?However a very fortunate outcome was that the impedance of putting each crossed yagi in parallel with the other resulted in nice combined impedance.? ?I chose to use short feedlines that (corrected for velocity factor) were 1/2 wavelength, for the purpose of allowing me to use a nanoVNA to try and estimate the actual feed point impedance.? ?It worked!
?
Putting the yagis in parallel using a BNC T-connector resulted in an almost perfect SWR on my 70cm set and tolerable on the 2meter set.? ??
?
Here is a photo of the final antenna, with the booms and yagi's now implemented in standard 3/4 inch Schedule 40 PVC from Home Depot:
?
?
I'm still very very new at all of this, but I have now been able send and receive AX.25 (packet) to the ISS very easily on 2 meters.? ?This is an APRS digipeater, so acts a little differently than normal digipeaters I'm familiar with.? ? ?I'm still working on figuring out the best software with which to approach it -- there are LOTS of users so it is a big crowded!
?
Working my way back up to attempting the LINEAR satellites.? ?In the meantime, I have now worked out how to control the rotators remotely over WIFI using a raspberry pi to run the rotctld.? ?That will be for another post here.
?
So far the Yagi's seem to be working amazingly well for the homebrew way that i built them!? (the box on the base is just for stability weighting)
?
Gordon KX4Z
?
|
Re: Homebrew satellite control system that can run on sBitx
I have now gotten an elevation system working very well using a linear actuator (12V) from Amazon.? ?Also created crossed yagi's to allow for circular polarization.? ? Using "J" half-folded dipole driven elements has turned out very well.? ? The impedances of these driven elements wasn't as large as I had expected (they are dragged downward in impedance by the influence of the nearby reflector and director).? ?However a very fortunate outcome was that the impedance of putting each crossed yagi in parallel with the other resulted in nice combined impedance.? ?I chose to use short feedlines that (corrected for velocity factor) were 1/2 wavelength, for the purpose of allowing me to use a nanoVNA to try and estimate the actual feed point impedance.? ?It worked!
?
Putting the yagis in parallel using a BNC T-connector resulted in an almost perfect SWR on my 70cm set and tolerable on the 2meter set.? ??
?
Here is a photo of the final antenna, with the booms and yagi's now implemented in standard 3/4 inch Schedule 40 PVC from Home Depot:
?
?
I'm still very very new at all of this, but I have now been able send and receive AX.25 (packet) to the ISS very easily on 2 meters.? ?This is an APRS digipeater, so acts a little differently than normal digipeaters I'm familiar with.? ? ?I'm still working on figuring out the best software with which to approach it -- there are LOTS of users so it is a big crowded!
?
Working my way back up to attempting the LINEAR satellites.? ?In the meantime, I have now worked out how to control the rotators remotely over WIFI using a raspberry pi to run the rotctld.? ?That will be for another post here.
?
So far the Yagi's seem to be working amazingly well for the homebrew way that i built them!? (the box on the base is just for stability weighting)
?
Gordon KX4Z
?
|
Re: zBitX offset waterfall passband
I think the RIT got turned on in the second photo (off in the 1st) as I was playing around trying to fix that display offset error. It made no difference.
?
However, I did get the odd frequency fixed in the second photo. Connecting via sbitx.local and adjusting tuning seemed to get everything aligned on the display for the correct frequency on the HDMI screen matching the frequency tuned to, but the offset which only appears on the zBitX screen remains. I also got VNC connected, but I am having problems with that mode other than viewing.
|
I agree and would like to add. It is also possible that due to the higher load, the transmission will be noisy (50hz) which will degrade the sound of the FT8. HA8LKT Laci
On Fri, May 23, 2025 at 02:02 AM, Li Cao wrote:
I¡¯m using a PD power supply that comes with my MacBook computer along with a 9v trigger cable rated at 5 amps. But I cannot set Drive beyond 60 with FT8 on 20 meters. If is over 60, the zBitx restarts when transmitting . I don¡¯t know it¡¯s the trigger cable or the PD voltage drop.
?
Exactly. The current consumption during transmission is higher than what your power supply can handle, which is why the voltage drops.
The device turns off due to the low voltage, as it drops out of transmission and the voltage increases again, which is why it starts again.
--
Gyula HA3HZ
|
On Fri, May 23, 2025 at 02:02 AM, Li Cao wrote:
I¡¯m using a PD power supply that comes with my MacBook computer along with a 9v trigger cable rated at 5 amps. But I cannot set Drive beyond 60 with FT8 on 20 meters. If is over 60, the zBitx restarts when transmitting . I don¡¯t know it¡¯s the trigger cable or the PD voltage drop.
?
Exactly. The current consumption during transmission is higher than what your power supply can handle, which is why the voltage drops.
The device turns off due to the low voltage, as it drops out of transmission and the voltage increases again, which is why it starts again.
--
Gyula HA3HZ
|
Re: zBITx First Impressions from M7NDB
#zbitx
On Fri, May 23, 2025 at 02:19 AM, Li Cao wrote:
How do you know yours is truncating TX in ?FT8? I did completed some QSOs but success rate is very low. For me it seems it transmits fully judging by the losing of waterfall (all striped yellow bar) and presence of tone. But seems few people other than PSKreporter can hear me¡
For low power you need a well-radiating antenna, then you will be successful in the connection.
It is advisable to call the CQ station and not the other way around that you are CQing, then the QSO may be possible, but you must transmit on a clear frequency so that they can really hear you and your transmission is not suppressed by another station transmitting on the same frequency.
--
Gyula HA3HZ
|
If I recall correctly, the USB-C PD standard is 9V at 3 A max. I suspect when the zBitx transmits, the current draw exceeds 3 amps and the PD adaptor shuts down and then restarts. ?
|
Re: Up and Running Fully Portable
Yeah, I ran into the same issue with that OTG adapter. I think it's not so much an OTG adapter as a crisp, tasty waffle. I had one around, and, like you, got my keyboard and mouse working. Then I paired a handheld keyboard with a trackpad built in, and I'll likely use that. I think I'm going to make a technical bag to go along with the radio's go-bag, one with an HDMI cable, a 14-inch portable screen, and a better bluetooth keyboard I have that's got a built in trackball. Each of those things is bigger than the repurposed photographer's bag I'm using for the radio and its immediate gear. I need to get the radio out and update the firmware and UI anyway, so I'll do the pairing for the new keyboard while I have it out.
I got an 8-pack of 18650 batteries and a USB-C powered 4-place charger that has been a real workhorse. I like that it doesn't need a mains plug. I'm about halfway through assembly of a 5-band link dipole. Once I get the basic build put together, I'll run it up a telescoping mast and tune it up. Then I'll crimp on bullet lugs to make connecting the links easy, and it'll be in service. I've got a 3-band link dipole already, but I need to replace the connectors in the links, and it doesn't have my favorite bands in it. Besides, I made the new one out of Kev-Flex. Durable.
-=-=-=-=-=-=-=-=- 73, Gwen, NG3P
BitXers,
??? Been playing with and learning
my new zBitx and I am having a blast.? I have made a couple CW
contacts almost immediately after receiving my unit.? I had a
couple unexpected hiccups in that I wasn't prepared for the
"Mini-HDMI".? The other was the USB-OTG adapter that came with
it was bad.? Fortunately I had another stuffed in a drawer and
decided to try it.? Keyboard came right up and I was able to get
the unit up in Host mode.? I paired up my bluetooth keyboard so
I no longer have to deal with the USB port for that.
I am running a portable 16inch (USB
powered) monitor along with the wireless keyboard and can run
the rig on either 18650 batteries or my Bioenno 1212Ah based
battery box.? Got the clock sync'd up and started up FT8 on 20m
and made my first contact within in a minute....
Great start so far.? It's not a KX2
but this little unit is a lot of fun especially with all the
build in apps which I still need to play with.
Attached is a couple of photos.
--
"POWER, WE DON'T NEED NO STICKIN' POWER" - EVERY KX2 OWNER
Always respect the airwaves,
73 de KI7PBR, Gary
|
Up and Running Fully Portable
BitXers,
??? Been playing with and learning
my new zBitx and I am having a blast.? I have made a couple CW
contacts almost immediately after receiving my unit.? I had a
couple unexpected hiccups in that I wasn't prepared for the
"Mini-HDMI".? The other was the USB-OTG adapter that came with
it was bad.? Fortunately I had another stuffed in a drawer and
decided to try it.? Keyboard came right up and I was able to get
the unit up in Host mode.? I paired up my bluetooth keyboard so
I no longer have to deal with the USB port for that.
I am running a portable 16inch (USB
powered) monitor along with the wireless keyboard and can run
the rig on either 18650 batteries or my Bioenno 1212Ah based
battery box.? Got the clock sync'd up and started up FT8 on 20m
and made my first contact within in a minute....
Great start so far.? It's not a KX2
but this little unit is a lot of fun especially with all the
build in apps which I still need to play with.
Attached is a couple of photos.
--
"POWER, WE DON'T NEED NO STICKIN' POWER" - EVERY KX2 OWNER
Always respect the airwaves,
73 de KI7PBR, Gary
|
So if we are talking about the HRCC video and how his radio was resetting, he posted a follow up video and admitted that he used a 1A power supply. When he connected a 3.5A power supply, problem solved.
? ?I agree just having a solid aluminum baseplate as a heatsink with no mechanical ventilation could be an issue, I ordered a thermoelectric cooling fan that will attach to the back of the radio and that does add about 2 ounces. Despite these issues, I don¡¯t mind tinkering with radios and think it will be a fun experiment.?
? I can always take my G90 out if it doesn¡¯t work out. ? Best ?regards & 73
Jay KK7BVY
?
?
Sent: Thursday, May 22, 2025 7:03 PM
Subject: Re: [BITX20] Safe to buy?
?
On Thu, May 22, 2025 at 08:57 AM, Jay Bremner wrote:
I ordered one because I can deal with these minor issues, it
weighs under a pound, so perfect for POTA/SOTA and self-contained digital
modes.
?
Personally I think the issues with current draw and heat generation make it
less than perfect for POTA/SOTA and self-contained digital modes.? The
review I linked has these two items as the first two negative points for the
radio.
?
Hopefully these things will be improved over time, but from what I read
here it sounds like most people are operating them from home using wall current
and have added cooling solutions that add weight, as opposed to attacking the
root cause of excess current draw and heat generation.?
?
--
Regards,
Dave, N1AI
|
Re: zBITX Crashes - Suspect Memory Leak
#zbitx
Hi Jody,
?
New user/developer here and just tipping my toe in the water.? Regarding debouncing the key interrupts I wonder if you tried or considered disabling the GPIO interrupt as the first action in the IRQ handler, doing the IRQ business and renabling the interrupt after a small debouncing delay?? That is how I have done it on bare metal or RTOS projects I have done.? I did some research and the RPi OS doesn't make this straightforward to do without modifying the kernal, but I have seen workarounds to do this by poking /dev/mem register locations.
?
72, John - N2AFU
|
From: Dave, N1AI via groups.io
Sent: Thursday, May 22, 2025 7:03 PM
Subject: Re: [BITX20] Safe to buy?
?
On Thu, May 22, 2025 at 08:57 AM, Jay Bremner wrote:
I ordered one because I can deal with these minor issues, it
weighs under a pound, so perfect for POTA/SOTA and self-contained digital
modes.
?
Personally I think the issues with current draw and heat generation make it
less than perfect for POTA/SOTA and self-contained digital modes.? The
review I linked has these two items as the first two negative points for the
radio.
?
Hopefully these things will be improved over time, but from what I read
here it sounds like most people are operating them from home using wall current
and have added cooling solutions that add weight, as opposed to attacking the
root cause of excess current draw and heat generation.?
?
--
Regards,
Dave, N1AI
|
Re: zBITx First Impressions from M7NDB
#zbitx
John,? How do you know yours is truncating TX in ?FT8? I did completed some QSOs but success rate is very low. For me it seems it transmits fully judging by the losing of waterfall (all striped yellow bar) and presence of tone. But seems few people other than PSKreporter can hear me¡
toggle quoted message
Show quoted text
On May 22, 2025, at 3:45?PM, HA3HZ via groups.io <gyula@...> wrote:
? Shielding between the display and the RPi and shielding of the flexible connecting wire.
For sbitx I use copper foil and Kapton foil as electrical insulator because it can withstand temperatures better.
Another consideration is a single point ground, similar to the single point grounding of the station.
Ground loops should be avoided.
--
Gyula HA3HZ
|
I¡¯m using a PD power supply that comes with my MacBook computer along with a 9v trigger cable rated at 5 amps. But I cannot set Drive beyond 60 with FT8 on 20 meters. If is over 60, the zBitx restarts when transmitting . I don¡¯t know it¡¯s the trigger cable or the PD voltage drop.
toggle quoted message
Show quoted text
On May 22, 2025, at 1:40?PM, Robert Fairbairn via groups.io <bobfa@...> wrote:
? I have been using the batteries and a 9v Mean Well GST40A09-P1. ?
?
?
?
|
I haven't received my zbitx and haven't had my hands on it yet, so maybe my question is moot.?
?
With inexpensive and reliable GPS Modules such as the GT-U7, is there a way to implement it into the zbtix for time sync or maybe even location??
?
The GT-U7 can ouput NEMA data via serial USB or TTL. I have used this module (with Arduino) and it has been sensitive enough to use inside my house.
?
My first thought is to use an Arduino as an NTP server for the zbitz to sync to. However, I am curious if a more direct way could be possible so it can be used without networking.
?
Ed
?
?
|
Dave, N1AI
Vic WA4THR
HA3HZ
Gwen Patton
Gary-KI7PBR
Jay Bremner
Jens/HB9JOI
Ed K.