Re: #sbitx A cool (kludgy) way to remotely use the sbitx
#sBitx
That's not entirely accurate. VNC does not use the X Windows protocol, It uses its own Remote Frame Buffer protocol, which is a simple one that just sends the bitmap of the screen (compressed to keep the bandwidth requirement reasonable), along with handling keyboard and mouse information. VNC clients are available for just about any modern computing device, including Linux, Windows, Mac, iOS, and Android devices.
VNC DOES do the same job from the end user's point of view, which is to allow you to remotely operate a computer. That's the important takeaway here.
The X Windows protocol is complex and sends both text and graphics that?get?rendered on the user's system, requiring an X server to run on the destination computer to interpret. (The terminology of X server and client feels backwards to me: the end user sits in front of an X SERVER and the remote system being operated is a CLIENT.) X servers (remember the backwards designations) are also available for many OSes, but installing one on a system where X is not the native display method (like Windows) is more complex than installing a VNC client. One of the reasons it is designed that way is that it was meant to work back in the days of low bandwidth connections; just sending the descriptions of what will appear on the screen and letting the user's system render them often requires fewer bits to be sent.
On Mon, Sep 5, 2022 at 9:55 AM Evan Hand < elhandjr@...> wrote: Farhan,
The Raspberry Pi OS has VNC built in.? That will open an X-window environment on any operating system.? Here is a link on how to set up to use VNC on a Raspberry Pi:
73
Evan
AC9TU
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thanks...that worked..
having a couple of other issues but not related to the code it appers.
thanks
Vince
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Tayda looks like a good steer for a cheap PFET.
But be aware that the on resistance of an IRF5305 is 60 milli-Ohms, which is 20 times more than the part Gordon was working with.
So if your rig draws 10 Amps there will be a 10*0.060=0.6 volt drop across this PFET, and you may as well just use a big Schottky diode in series.
Also, IR/Infineon consider this part to be obsolete, so now only made by no-name second tier clone manufacturers.
For example, these guys list the manufacturer as "various".
Not necessarily a bad thing, there are thousands of uBitx's out there with a clone no-name Nano,
and the Nano is far more complicated than a PFET.
I've bought a bunch of stuff from Tayda at their alarmingly low prices, it all seems to work just fine.
Jerry, KE7ER
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On Mon, Sep 5, 2022 at 11:41 AM, JerryP wrote:
If you're looking for a P-Channel MOSFET for a power switch then this may be able to use a IRF5305 - TO-220, 55V, 31A, 0.06Ohm RDS On @$0.78 each:
Tayda has a $5.00 minimum order and their USPS shipment is 8-16 days and low cost.? While they may not have everything, it's very low priced and good quality.
?
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If you're looking for a P-Channel MOSFET for a power switch then this may be able to use a IRF5305 - TO-220, 55V, 31A, 0.06Ohm RDS On @$0.78 each: Tayda has a $5.00 minimum order and their USPS shipment is 8-16 days and low cost.? While they may not have everything, it's very low priced and good quality.
Thanks, Jerry.? ?Our County had spent > $100,000 on our group to provide 14 go-boxes with Public Service Motorolla truked?radios as well as far less expensive ham radios....because the hurricane shelters are steel reinforced concrete buildings (schools) and the police handhelds simply won't get out. ..? With hundreds of people cooped p in a shelter....the police Need To Reach Backup if there is a disturbance...hence our ham radio group.
We were terrified of destroying one of those radios because large storage batteries can ALWAYS be misconnected with ring connectors to their bolt-terminals....and hence this project.? ?We built a couple of dozen AT LEAST when mosfets were still easily obtainable.? ?Now it is harder to find.? ? You want to arrange for very low series resistance because it means much much less heat dissipation.? ? ? When the mosfets get hot, their series resistance goes up -- BAD CYCLE!!
I have this on my 7300 and still a spare or two sitting around, so one will go on the sBitx.? ? We have them on every key radio in our Emergency Operations Center.? ?People under STRESS will make mistakes.? ? You could probabaly?build the same circuit with an N channel....if yu are willing to break the ground wire, which we didn't want to do.
This is something that can be built MUCH EASIER with SMD's which?are much more readily available.? ?But I don't have that ability to fool with.? ?Others could do it much more easily than I.
Gordon
Correction for the final sentence:
?If the user does NOT fuse the battery with a fast blow fuse
of the appropriate current rating, then a reversed battery can destroy the rig.
On Mon, Sep 5, 2022 at 09:20 AM, Jerry Gaffke wrote:
If the user does fuse the battery with a fast blow fuse
of the appropriate current rating, then a reversed battery can destroy the rig.
--
Jerry, AC9NM ÊÖÖеÄÄñÔÚ¹àľ´ÔÖÐÖµÁ½¸ö
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It may be a step backward for some but I have an assembled uBITX V6 for sale. It has been used very little on SSB with excellent results.? If interested, please contact me by email to discuss details.? Thanks, Clyde - W7CZA?
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Re: #sbitx A cool (kludgy) way to remotely use the sbitx
#sBitx
Mac users will need to be running an X11 server (see )
On Mon, Sep 5, 2022 at 12:37 AM Ashhar Farhan < farhanbox@...> wrote: First, enable ssh on the sbitx. 1. From the main menu, Choose Preferences > Raspberry Pi Configuration 2. Click on the Interfaces tab 3. On the tab and enable SSH if not enabled, Click OK 4. From a terminal on the sbitx, type ifconfig and note the IP address of the sbitx. In my case it was 192.168.1.142
Second, from your linux laptop (yeah, it wont work with windoze, it might work on a mac, let us know) 1. Open a terminal window 2. Enable remote x clients to connect with the command "xhost?+" (without quotes) 3. Next, ssh to your sbitx with a special option like this : ssh [email protected] -X
Enter your password (by default it is hf12345).
4. Now you are connected to the sbitx. Go into the sbitx directory
and execute the program like this:
cd sbitx
./sbitx
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Thanks, Jerry.? ?Our County had spent > $100,000 on our group to provide 14 go-boxes with Public Service Motorolla truked?radios as well as far less expensive ham radios....because the hurricane shelters are steel reinforced concrete buildings (schools) and the police handhelds simply won't get out. ..? With hundreds of people cooped p in a shelter....the police Need To Reach Backup if there is a disturbance...hence our ham radio group.
We were terrified of destroying one of those radios because large storage batteries can ALWAYS be misconnected with ring connectors to their bolt-terminals....and hence this project.? ?We built a couple of dozen AT LEAST when mosfets were still easily obtainable.? ?Now it is harder to find.? ? You want to arrange for very low series resistance because it means much much less heat dissipation.? ? ? When the mosfets get hot, their series resistance goes up -- BAD CYCLE!!
I have this on my 7300 and still a spare or two sitting around, so one will go on the sBitx.? ? We have them on every key radio in our Emergency Operations Center.? ?People under STRESS will make mistakes.? ? You could probabaly?build the same circuit with an N channel....if yu are willing to break the ground wire, which we didn't want to do.
This is something that can be built MUCH EASIER with SMD's which?are much more readily available.? ?But I don't have that ability to fool with.? ?Others could do it much more easily than I.
Gordon
Correction for the final sentence:
?If the user does NOT fuse the battery with a fast blow fuse
of the appropriate current rating, then a reversed battery can destroy the rig.
On Mon, Sep 5, 2022 at 09:20 AM, Jerry Gaffke wrote:
If the user does fuse the battery with a fast blow fuse
of the appropriate current rating, then a reversed battery can destroy the rig.
|
Correction for the final sentence:
?If the user does NOT fuse the battery with a fast blow fuse
of the appropriate current rating, then a reversed battery can destroy the rig.
toggle quoted message
Show quoted text
On Mon, Sep 5, 2022 at 09:20 AM, Jerry Gaffke wrote:
If the user does fuse the battery with a fast blow fuse
of the appropriate current rating, then a reversed battery can destroy the rig.
|
Gordon's construction manual for the PFET reverse protection circuit is excellent, well worth reading.? ?Be sure to follow his instructions and test with forward and reverse power applied, at maximum voltage and current draw.? Test into some cheap load, not your transceiver. Many people implement this without quite understanding how it works.? That can be killer, since a backwards PFET can seem to work, but offers zero protection. /g/BITX20/message/35434I have seen several how-to web pages that have the PFET in backwards, and one case of several hundred QRP transceiver kits going out with the PFET backwards. It seems to work, but gives no reverse polarity protection. Much of the difficulty is due to the fact that this is a PFET, not an NFET like the IRF510. So the voltages at the drain and gate with respect to the source are of the? opposite polarity of what you expect when operating normally in the linear region. Also, this PFET is in a circuit where it doesn't quite operate normally, the body diode plays an important part and should be included in the circuit drawing to make the operation a bit more obvious. At power on with the correct battery orientation, it is the intrinsic body diode that supplies power to the rig, going from the battery into the PFET drain and out of the PFET source to the rig. At this point, it is as if we have a simple diode in series with the battery as reverse protection.? As the voltage at the PFET source rises, the voltage from gate to source goes negative and the PFET starts turning on.? Once we have about minus 10 volts from gate to source, the PFET is fully on and there is just a couple mili-Ohms of resistance impeding current flow, which gives much lower losses than a series schottky diode would. It is often good enough to have a wimpy reverse protection scheme for everything except the final NFET's in the rig (a schottky diode, an LM2940CT-12), and?depend on a fuse or polyswitch to limit current through the NFET finals.? Any reverse voltage across most NFET's will flow harmlessly through the NFET's body diode.? But when adding this to a commercial rig, the minor hack of just adding this circuit where power enters the rig makes spending a few bucks on a big PFET a good investment. Lots of commercial rigs have a shunt schottky power diode across the 12v input connector, it conducts when the battery is backwards and blows the fuse.? However, they may not? include a fuse inside the rig.? If the user does fuse the battery with a fast blow fuse of the appropriate current rating, then a reversed battery can destroy the rig. Jerry, KE7ER ?
On Sun, Sep 4, 2022 at 02:45 PM, Gordon Gibby wrote:
In our neck of the words, if a radio is important to us we build a polarity protector that connects directly to it. ?No battery or anything is allowed to connect direct again, must go through our polarity protector
?
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?
?
?
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This isn't a great choice, but it would work for a modest power transceiver such as the sBitx and there are > 400 in stock at Digieky.
This is a much better choice and < $1 but you have to purchase?> 400 to get them.
It is amazing how thoroughly some actors can mess up the world productive capacity.
Gordon
On Mon, Sep 5, 2022 at 7:03 AM Gordon Gibby via <docvacuumtubes= [email protected]> wrote: Thanks for all the comments. 1.? It is difficult to fit ANYTIHNG inside an Icom 7300, so we build them externally for those and for $5000 police/fire transceivers.? ?Yes, it is better to install INSIDE...but sometimes you simply cannot. 2.? We previously used exactly what one commenter suggested -- the parallel reverse diode and series fuse.? ?Then one of my volunteers showed me a destroyed system where the diode didn't manage to blow the fuse in time for some fancy current measruing?gizmo.? ?Oops!? ?THat was the experience that got me working. 3.? Almost all of the P channel enhancement MOSFETS out there are very similar except for their series Rds-on? ? Most of them are quoted at a gate voltage of -10 (with reference to the source) and thus they are fairly interchangeable.? ?SOME (very few) have a protective zener built in to protect the vulnerable GATE but not very many, hence the zener built into the circuit in our simple (plagiarized) design. 4.? Yes, Max is right, these through-hole devices keep showing up--and then being made obsolete and disappearing.? ?However, the SMD versions are readily available.? ?I bought some -- yikes they are smaller than I like dealing with -- but then I found A NEW SUPPLIER of the automotive-market p-channel enhancements that had just what I was looking for and CHEAP.? ? I sent y'all the note quickly and haven't the time to find you that part instantly, but it (or the NEXT replacement) exists.? ?The worldwide governmental intrusion into markets has upset all manner of manufacturing and thus we have shortages of all kinds, but there is generally always something out there.? ?? 5.? I can't remember, but I think I made the PCB availble as a Project on ? ? ?It isn't a great design.? ?It did however, allow a couple dozen to be made in our town and successfully.? ?Add solder or wires to the traces if you need a lot more current capability.? ?The MOSFETS used to be easily available so we put as many as 4 on there to handle 25 Amps.? ??
Perhaps I can find my notes and the latest enhancement mostfet out there that is available.? ?They all seem to have the same PINOUT as well, but of course, please check that.? ?In our design they lose less voltage THAN THE CONNECTORS!!!? ?And thus there is no need for heat sinks at all.? ?Amazing.? ?For a guy who started in vacujm tubes 12AX7 and 6146 and 811A....then had to learn bipolar transistors and their wierd?nonlinearities, to have some astonishingly low Rds-on in a MOSFET as a near perfect "switch" (at dc) is just amazing.? ??
Happy homebrewing! 73 Gordon KX4Z
Good luck finding the mosfet! The part has been superseded (change the last digit in the p/n from a 1 to a 2) but I couldn't find them anywhere. Mouser shows a lead time of 52 weeks which basically means they don't know when they will have them.
Max
On Sunday, September 4, 2022, 10:59:06 PM CDT, otalado < s53c.lado@...> wrote:
Hi, Gordon
while it is true that just showing a diode into the power supply line is cheap & quick, the solution you suggested is, without doubt, a lot better. In fact, I'll order (or produce) some PCB for the protector. Yet I strongly believe that such protection should always be built inside the box that needs protection!
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Re: #sbitx A cool (kludgy) way to remotely use the sbitx
#sBitx
toggle quoted message
Show quoted text
On Mon, Sep 5, 2022, 7:25 PM Evan Hand < elhandjr@...> wrote: Farhan,
The Raspberry Pi OS has VNC built in.? That will open an X-window environment on any operating system.? Here is a link on how to set up to use VNC on a Raspberry Pi:
73
Evan
AC9TU
|
Re: #sbitx A cool (kludgy) way to remotely use the sbitx
#sBitx
Farhan,
The Raspberry Pi OS has VNC built in.? That will open an X-window environment on any operating system.? Here is a link on how to set up to use VNC on a Raspberry Pi:
73
Evan
AC9TU
|
Thanks for all the comments. 1.? It is difficult to fit ANYTIHNG inside an Icom 7300, so we build them externally for those and for $5000 police/fire transceivers.? ?Yes, it is better to install INSIDE...but sometimes you simply cannot. 2.? We previously used exactly what one commenter suggested -- the parallel reverse diode and series fuse.? ?Then one of my volunteers showed me a destroyed system where the diode didn't manage to blow the fuse in time for some fancy current measruing?gizmo.? ?Oops!? ?THat was the experience that got me working. 3.? Almost all of the P channel enhancement MOSFETS out there are very similar except for their series Rds-on? ? Most of them are quoted at a gate voltage of -10 (with reference to the source) and thus they are fairly interchangeable.? ?SOME (very few) have a protective zener built in to protect the vulnerable GATE but not very many, hence the zener built into the circuit in our simple (plagiarized) design. 4.? Yes, Max is right, these through-hole devices keep showing up--and then being made obsolete and disappearing.? ?However, the SMD versions are readily available.? ?I bought some -- yikes they are smaller than I like dealing with -- but then I found A NEW SUPPLIER of the automotive-market p-channel enhancements that had just what I was looking for and CHEAP.? ? I sent y'all the note quickly and haven't the time to find you that part instantly, but it (or the NEXT replacement) exists.? ?The worldwide governmental intrusion into markets has upset all manner of manufacturing and thus we have shortages of all kinds, but there is generally always something out there.? ?? 5.? I can't remember, but I think I made the PCB availble as a Project on ? ? ?It isn't a great design.? ?It did however, allow a couple dozen to be made in our town and successfully.? ?Add solder or wires to the traces if you need a lot more current capability.? ?The MOSFETS used to be easily available so we put as many as 4 on there to handle 25 Amps.? ??
Perhaps I can find my notes and the latest enhancement mostfet out there that is available.? ?They all seem to have the same PINOUT as well, but of course, please check that.? ?In our design they lose less voltage THAN THE CONNECTORS!!!? ?And thus there is no need for heat sinks at all.? ?Amazing.? ?For a guy who started in vacujm tubes 12AX7 and 6146 and 811A....then had to learn bipolar transistors and their wierd?nonlinearities, to have some astonishingly low Rds-on in a MOSFET as a near perfect "switch" (at dc) is just amazing.? ??
Happy homebrewing! 73 Gordon KX4Z
Good luck finding the mosfet! The part has been superseded (change the last digit in the p/n from a 1 to a 2) but I couldn't find them anywhere. Mouser shows a lead time of 52 weeks which basically means they don't know when they will have them.
Max
On Sunday, September 4, 2022, 10:59:06 PM CDT, otalado < s53c.lado@...> wrote:
Hi, Gordon
while it is true that just showing a diode into the power supply line is cheap & quick, the solution you suggested is, without doubt, a lot better. In fact, I'll order (or produce) some PCB for the protector. Yet I strongly believe that such protection should always be built inside the box that needs protection!
|
Good luck finding the mosfet! The part has been superseded (change the last digit in the p/n from a 1 to a 2) but I couldn't find them anywhere. Mouser shows a lead time of 52 weeks which basically means they don't know when they will have them.
Max
On Sunday, September 4, 2022, 10:59:06 PM CDT, otalado <s53c.lado@...> wrote:
Hi, Gordon
while it is true that just showing a diode into the power supply line is cheap & quick, the solution you suggested is, without doubt, a lot better. In fact, I'll order (or produce) some PCB for the protector. Yet I strongly believe that such protection should always be built inside the box that needs protection!
|
I've never seen a commercial radio that had a diode in series with the 12v input. Instead they put a diode across the power input so that it conducts if the input power is reversed and blows a fuse.
I like?Phil Salas AD5X idea for an over voltage AND reverse voltage protector.
Max KG4PID
On Sunday, September 4, 2022, 11:26:25 PM CDT, Ashhar Farhan <farhanbox@...> wrote:
The polarity protector is the better idea. Simply because the diode can get very very hot. The sbitx can draw upto 10A of current. Across a diode like 1N4007, the voltage drop is about 0.7V, the diode will have to dissipate 10 x 0.7A = 7 watts of power during transmit. This is one reason why we don't switch the power to the power amplifier through T/R line, the power involved is just too much. - f
Hi, Gordon
while it is true that just showing a diode into the power supply line is cheap & quick, the solution you suggested is, without doubt, a lot better. In fact, I'll order (or produce) some PCB for the protector. Yet I strongly believe that such protection should always be built inside the box that needs protection!
|
#sbitx A cool (kludgy) way to remotely use the sbitx
#sBitx
First, enable ssh on the sbitx. 1. From the main menu, Choose Preferences > Raspberry Pi Configuration 2. Click on the Interfaces tab 3. On the tab and enable SSH if not enabled, Click OK 4. From a terminal on the sbitx, type ifconfig and note the IP address of the sbitx. In my case it was 192.168.1.142
Second, from your linux laptop (yeah, it wont work with windoze, it might work on a mac, let us know) 1. Open a terminal window 2. Enable remote x clients to connect with the command "xhost?+" (without quotes) 3. Next, ssh to your sbitx with a special option like this : ssh [email protected] -X
Enter your password (by default it is hf12345).
4. Now you are connected to the sbitx. Go into the sbitx directory
and execute the program like this:
cd sbitx
./sbitx
|
The polarity protector is the better idea. Simply because the diode can get very very hot. The sbitx can draw upto 10A of current. Across a diode like 1N4007, the voltage drop is about 0.7V, the diode will have to dissipate 10 x 0.7A = 7 watts of power during transmit. This is one reason why we don't switch the power to the power amplifier through T/R line, the power involved is just too much. - f
Hi, Gordon
while it is true that just showing a diode into the power supply line is cheap & quick, the solution you suggested is, without doubt, a lot better. In fact, I'll order (or produce) some PCB for the protector. Yet I strongly believe that such protection should always be built inside the box that needs protection!
|
Hi, Gordon
while it is true that just showing a diode into the power supply line is cheap & quick, the solution you suggested is, without doubt, a lot better. In fact, I'll order (or produce) some PCB for the protector. Yet I strongly believe that such protection should always be built inside the box that needs protection!
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Vince, This is a stupid bug that will be soon fixed. Type? ?git reset --hard ?git pull The git reset command will override and reset the files. - f
On Mon, Sep 5, 2022, 6:22 AM Vince Loschiavo < vince320@...> wrote: I guess it updated, would like to know where to look to see if / what was updated.
Vince
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Re: Ubitx version 3 heatsink
Thanks for the info.? I have a lot to learn.
-John
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Shirley Dulcey KE1L
Vince N2AIE
JerryP