Topics

12V Power for the Pi (was Re: [RaspberryPi-4-HamRadio] Getting back to the RPi)

Michael WA7SKG
 

And yet the previously referenced article ( https://www.amsat.org/amsat/articles/g3ruh/109.html) says:

"One is that the channel is not DC coupled. It could never be so in an FM system unless one could guarantee both transmitter and receiver were always exactly on frequency and had no drift. As this is virtually impossible to achieve, one simply AC couples the channel, i.e. gives it a response down to a few Hz, and exploits the feature of the randomised data that it has a negligible DC component."

I always thought AC coupling was often via a transformer.

That's okay, I'm a native of the State of Confusion.

I'll crawl back under my rock now.

Michael WA7SKG



Eric wrote on 12/31/19 8:31 PM:

I think I remember reading that 9600 bps requires DC coupling to the modulator.
Transformer coupling would be a problem if that is the case.
Eric
WB6TIX
On Tue, Dec 31, 2019, 20:48 Michael WA7SKG <wa7skg@... <mailto:wa7skg@...>> wrote:
"the Signalink will not work at the higher speed because it has
transformers in the audio chain."
Huh?? It is audio. Maybe a greater bandwidth due to the speed, but
audio
nonetheless. Entertainment system audio often goes over 15 kHz through
transformers. I would be interested in understanding why the Signalink
cannot do the higher speeds because it has transformers. I always like
to learn new things.
Michael WA7SKG
Bill Vodall wrote on 12/31/19 4:13 PM:
>
> The DRAWS board is designed for 9600 baud which most other sound card
> interfaces won't handle.  In particular, as handy as it is, the
> Signalink will not work at the higher speed because it has
> transformers in the audio chain.
>

Eric
 

I think I remember reading that 9600 bps requires DC coupling to the modulator.

Transformer coupling would be a problem if that is the case.

Eric
WB6TIX

On Tue, Dec 31, 2019, 20:48 Michael WA7SKG <wa7skg@...> wrote:
"the Signalink will not work at the higher speed because it has
transformers in the audio chain."

Huh?? It is audio. Maybe a greater bandwidth due to the speed, but audio
nonetheless. Entertainment system audio often goes over 15 kHz through
transformers. I would be interested in understanding why the Signalink
cannot do the higher speeds because it has transformers. I always like
to learn new things.

Michael WA7SKG

Bill Vodall wrote on 12/31/19 4:13 PM:
>
> The DRAWS board is designed for 9600 baud which most other sound card
> interfaces won't handle.  In particular, as handy as it is, the
> Signalink will not work at the higher speed because it has
> transformers in the audio chain.
>



Ray Wells
 

In simple terms 9600 is not audio tones, it's a data switching rate (actually at 4800 and doubled in the process) . For 9600 the frequency response of the signal chain is ideally down to a DC response which of course won't pass through a transformer. One of the "fathers of 9600 packet was James Miller G3RUH who produced various modems. His writings on 9600 are worth a read for some detail about what works and what doesn't. Try this for starters https://www.amsat.org/amsat/articles/g3ruh/109.html

HTH
Ray vk2tv

On 1/1/20 3:02 pm, Daniel Holmes wrote:
It’s always been my understanding it’s not the transformers that are the problem, it’s where the audio is injected—if it’s injected in the mic input then you are limited to 1200 baud, but if you inject elsewhere (the IF? I can’t remember) the you can get 9k6. A lot of modern radios have inputs for data that take 9k6. I think any soundcard can connect to those inputs for higher baud rates via direwolf. The signalink and other specialized cards I think have optical isolators that isolate from the computer. ‘Course it is NYE, and I could be all wrong due to that. 

Dan

--
. Please pardon any mispelings or errors.


On Dec 31, 2019, at 8:48 PM, Michael WA7SKG <wa7skg@...> wrote:

"the Signalink will not work at the higher speed because it has transformers in the audio chain."

Huh?? It is audio. Maybe a greater bandwidth due to the speed, but audio nonetheless. Entertainment system audio often goes over 15 kHz through transformers. I would be interested in understanding why the Signalink cannot do the higher speeds because it has transformers. I always like to learn new things.

Michael WA7SKG

Bill Vodall wrote on 12/31/19 4:13 PM:

The DRAWS board is designed for 9600 baud which most other sound card
interfaces won't handle.  In particular, as handy as it is, the
Signalink will not work at the higher speed because it has
transformers in the audio chain.




Daniel Holmes
 

It’s always been my understanding it’s not the transformers that are the problem, it’s where the audio is injected—if it’s injected in the mic input then you are limited to 1200 baud, but if you inject elsewhere (the IF? I can’t remember) the you can get 9k6. A lot of modern radios have inputs for data that take 9k6. I think any soundcard can connect to those inputs for higher baud rates via direwolf. The signalink and other specialized cards I think have optical isolators that isolate from the computer. ‘Course it is NYE, and I could be all wrong due to that. 

Dan

--
. Please pardon any mispelings or errors.


On Dec 31, 2019, at 8:48 PM, Michael WA7SKG <wa7skg@...> wrote:

"the Signalink will not work at the higher speed because it has transformers in the audio chain."

Huh?? It is audio. Maybe a greater bandwidth due to the speed, but audio nonetheless. Entertainment system audio often goes over 15 kHz through transformers. I would be interested in understanding why the Signalink cannot do the higher speeds because it has transformers. I always like to learn new things.

Michael WA7SKG

Bill Vodall wrote on 12/31/19 4:13 PM:

The DRAWS board is designed for 9600 baud which most other sound card
interfaces won't handle.  In particular, as handy as it is, the
Signalink will not work at the higher speed because it has
transformers in the audio chain.



Michael WA7SKG
 

"the Signalink will not work at the higher speed because it has transformers in the audio chain."

Huh?? It is audio. Maybe a greater bandwidth due to the speed, but audio nonetheless. Entertainment system audio often goes over 15 kHz through transformers. I would be interested in understanding why the Signalink cannot do the higher speeds because it has transformers. I always like to learn new things.

Michael WA7SKG

Bill Vodall wrote on 12/31/19 4:13 PM:


The DRAWS board is designed for 9600 baud which most other sound card
interfaces won't handle. In particular, as handy as it is, the
Signalink will not work at the higher speed because it has
transformers in the audio chain.

Ed K6ESS
 

Tad came pretty close to a "Santa's wish list" card. I could pass on all the data logging, but all else is spot on. Santa, can you come thru with a late Christmas gift?

Ed K6ESS
Sacramento CA

Make everything as simple as possible,  but not simpler.  Albert Einstein

On Tue, Dec 31, 2019, 16:14 Bill Vodall <wa7nwp@...> wrote:
> Not, yet, interested in 1200 baud, especially at $150.

The DRAWS board is designed for 9600 baud which most other sound card
interfaces won't handle.  In particular, as handy as it is, the
Signalink will not work at the higher speed because it has
transformers in the audio chain.

DRAWS has suggested it will work at 19,200 but I'm waiting for them to
demo that - preferably with iPerf numbers...

Bill



 

Not, yet, interested in 1200 baud, especially at $150.
The DRAWS board is designed for 9600 baud which most other sound card
interfaces won't handle. In particular, as handy as it is, the
Signalink will not work at the higher speed because it has
transformers in the audio chain.

DRAWS has suggested it will work at 19,200 but I'm waiting for them to
demo that - preferably with iPerf numbers...

Bill

 

Patience maties.   Don’t knock anybody making a product which is pretty much exclusively for ham radio ops.  Hams are NOT that great of a market place.  We need all that we can get.  

The DRAWS is pretty cool if you want to be doing APRS stuff with Direwolf.  

I acknowledge that it doesn’t address the 12v backup power thing we’ve been talking about.  
This is my wishlist for a Raspberry PI backup and power control system:
  • Runs a Raspberry PI 3B, 3B+ or 4B @5.1vDC 
  • It is powered by a 11.5vDC to 15vDC mains/primary power source.  
  • Powered using Anderson PowerPole connection.
  • Provides backup power to the Raspberry PI with instant switchover if the primary power source goes below 11.5v (maybe configurable?)
  • It should have an on/off button or toggle to do a safe shutdown of the Raspberry PI.  
  • It should know if we turned off the PI using an external switch, that the PI should stay off until we turn it on, even of the main power and secondary power are removed and re-applied.   A toggle switch input is ideal for this since it has a real “OFF” state. 
  • Uses an unspecified battery for backup power, given some reasonable battery voltage (6.5v to 15v?).  
  • Supports an unspecified external charger for any particular battery and can remove the charger from the circuit when the battery is discharging.  
  • It should be configurable to do a self-declared Raspberry Pi shutdown if the battery backup battery goes below the configured voltage, and then return the Raspberry PI to powered-up only if the mains/PRIMARY source is present for a configured length of time. 
  • It should be able to tell us how l long the power was off for, and let us read the voltage of either mains/PRIMARY or battery input in real time.
  • It would be nice if it could log the voltage on each power input periodically whenever the switch is ON, regardless of whether running on primary/mains or battery.  Perhaps the log would increase the time between readings logarithmically if it runs out of memory space?  
  • It should have some RF immunity features built in, including ground-plane, a large tinned-thru-hole screw-hole for #4 screw to ground the unit, and maybe provision to insert ferrite beads and bypass caps in off-the-board circuits?  
  • It should be almost free (haha)
There aren’t many points not covered by the MOPI.  

I’m not particularly wedded to having a shield card/hat for a Raspberry PI.  I find the physical mounting of such units to be sloppy and access to switches, variable controls, and LEDs on stacked boards is difficult.  I’d prefer using a 6” USB cable, but I acknowledge the additional expense and in-circuit loss of such a thing.  
   Tadd / KA2DEW
   Raleigh NC




On Dec 30, 2019, at 12:30 PM, Daniel Holmes <danielh@...> wrote:

Eh, considering all that it does and the convenience factor I don’t think $150 is all that outrageous. I already have a Pi-TNC, Signalink, GPS puck, and the Mo-Pi, so it’s superfluous for me. The Mo-Pi handled my power requirements (namely multiple inputs and charging circuitry) better than the DRAWS HAT. Although it would be very convenient to have everything in one package.

Dan
--
Daniel Holmes, danielh@...
"Laugh while you can, monkey boy!" -- Lord John Whorfin


On Dec 30, 2019, at 10:22 AM, Michael WA7SKG <wa7skg@...> wrote:

Thanks for the suggestion, but I am not going to spend another $150+ for more hardware that is less capable than what I already have to do the work of a $7 buck-boost module.

Michael WA7SKG

John D Hays - K7VE wrote on 12/30/19 8:48 AM:
For Amateur Radio use, be sure to look at the DRAWS™ <http://www.nwdigitalradio.com/draws> board: 9-15 VDC input supply, sound card, dual radio interfaces, GPIO pin extensions, GPS (w/battery backed clock) -- all integrated into a Raspberry Pi HAT.
http://nwdigitalradio.com/shop/
--
John D. Hays
Kingston, WA
K7VE








chuck gelm <rpi4ham@...>
 

On 12/30/19 12:22 PM, Michael WA7SKG wrote:
Thanks for the suggestion, but I am not going to spend another $150+ for more hardware that is less capable than what I already have to do the work of a $7 buck-boost module.

Michael WA7SKG

+1

Not, yet, interested in 1200 baud, especially at $150.

...what I already have to do the work of a $50 single band, modem, transceiver, antenna, POE powered, outdoor rated, up to 144.4 Mbps, automatic-adaptive networking,

:-|

But, I love the Raspberry Pi. :-)

Chuck

Daniel Holmes
 

Eh, considering all that it does and the convenience factor I don’t think $150 is all that outrageous. I already have a Pi-TNC, Signalink, GPS puck, and the Mo-Pi, so it’s superfluous for me. The Mo-Pi handled my power requirements (namely multiple inputs and charging circuitry) better than the DRAWS HAT. Although it would be very convenient to have everything in one package.

Dan
--
Daniel Holmes, danielh@...
"Laugh while you can, monkey boy!" -- Lord John Whorfin

On Dec 30, 2019, at 10:22 AM, Michael WA7SKG <wa7skg@...> wrote:

Thanks for the suggestion, but I am not going to spend another $150+ for more hardware that is less capable than what I already have to do the work of a $7 buck-boost module.

Michael WA7SKG

John D Hays - K7VE wrote on 12/30/19 8:48 AM:
For Amateur Radio use, be sure to look at the DRAWS™ <http://www.nwdigitalradio.com/draws> board: 9-15 VDC input supply, sound card, dual radio interfaces, GPIO pin extensions, GPS (w/battery backed clock) -- all integrated into a Raspberry Pi HAT.
http://nwdigitalradio.com/shop/
--
John D. Hays
Kingston, WA
K7VE

Michael WA7SKG
 

Thanks for the suggestion, but I am not going to spend another $150+ for more hardware that is less capable than what I already have to do the work of a $7 buck-boost module.

Michael WA7SKG

John D Hays - K7VE wrote on 12/30/19 8:48 AM:

For Amateur Radio use, be sure to look at the DRAWS™ <http://www.nwdigitalradio.com/draws> board: 9-15 VDC input supply, sound card, dual radio interfaces, GPIO pin extensions, GPS (w/battery backed clock) -- all integrated into a Raspberry Pi HAT.
http://nwdigitalradio.com/shop/
--
John D. Hays
Kingston, WA
K7VE

 

For Amateur Radio use, be sure to look at the DRAWS™ board: 9-15 VDC input supply, sound card, dual radio interfaces, GPIO pin extensions, GPS (w/battery backed clock) -- all integrated into a Raspberry Pi HAT.
--
John D. Hays
Kingston, WA
K7VE

 

bbillp
 

The WittyPI III from UUGEAR will take input to 15V to power the Pi, the WittyPi also contains an accurate RTC and lots of automatic power up and power down programming options. I use 4 of these to control my sky cameras.

Any number of 7805 regulators and micro sized DC to DC regulators are available for 5 volts output. I also use OLD USB cables to connect power to the Pi as the wire conductors are large and can carry the current. Bill k6acj.

 

Daniel, I look forward to the results of your experiment.   Tadd

Tadd --- Sent from Planet X

On Dec 24, 2019, at 5:45 PM, Daniel Holmes <danielh@...> wrote:

That’s my plan—and from what I’ve read they are designed to use the bus correctly. 

Dan

--
. Please pardon any mispelings or errors.


On Dec 24, 2019, at 2:51 PM, Tadd KA2DEW in NC via Groups.Io <tadd@...> wrote:


I wonder if G8BPQ node + TNC-PI can share the i2C bus with the MOPI.


On December 24, 2019 at 1:40 PM, "Tadd KA2DEW in NC via Groups.Io" <tadd@...> wrote:

interesting.  ok.  so same scenario but in B> the Raspberry PI is left OFF.  Does it turn on when G or H?


On December 24, 2019 at 1:36 PM, Daniel Holmes <danielh@...> wrote:

If power is applied to the Pi while it is off it will turn on at G.

Dan
--
Daniel Holmes, danielh@...
"Laugh while you can, monkey boy!" -- Lord John Whorfin


On Dec 24, 2019, at 11:33 AM, Tadd KA2DEW in NC via Groups.Io <tadd@...> wrote:

Using the MOPI-2 In this scenario

A> mains are working.  
B> Start Raspberry PI
C> runs steady for a long time (weeks)
D> Mains go to 0v but are still hooked up.
E> battery eventually gets low
F> MOFI does LInux shutdown and turns off Raspberry PI
G> mains come back eventually
H>  battery charges
J> raspberry is provided power again

Is there a way to have the Raspberry PI come back on-line in H or J ?  

Thanks!
  Tadd - KA2DEW
  Raleigh NC USA


On December 24, 2019 at 11:39 AM, Daniel Holmes <danielh@...> wrote:

Good question on a monitor—I think the specs said it’ll only do about 2.5-3 amps, but there’s a way to switch in a 5V relay to power up the monitor. I personally run my Pi headless, and use VNC on my iPad to connect in (although I have a small wireless keyboard I use because typing on a virtual keyboard stinks.)

Dan
--
Daniel Holmes, danielh@...
"Laugh while you can, monkey boy!" -- Lord John Whorfin


On Dec 24, 2019, at 9:35 AM, Michael WA7SKG <wa7skg@...> wrote:

Dan,

THANK YOU! What a device! While you say expensive, it's only a few dollars more than the USBuddy and does so much more. The on/off switch is a big plus, as well as the HAT configuration. The only thing I'm not sure of is powering the monitor as well. As I am using the Smarti-Pi Touch Case, the RPi is not mounted directly to the monitor, so it is not powered through the IO pins, but from a separate USB connection. However, I do not think this is insurmountable.

Thanks again.

73,
Michael WA7SKG

Daniel Holmes wrote on 12/24/19 6:57 AM:
For running off a 12V supply, this is what I use: https://pi.gate.ac.uk/pages/mopi.html Seems to be pretty RF quiet.
Yeah, it’s a bit expensive, but I have it wired with an on/off switch to power up/power down the Pi cleanly, and it powers it down when the batteries are almost exhausted. I haven’t worked up the battery charger just yet, but it’ll be a handy part of my go-kit. I still need to figure out how to use more than 1 HAT on my Pi, but that’s just a bit of research—so many projects so little time.
Dan












Daniel Holmes
 

That’s my plan—and from what I’ve read they are designed to use the bus correctly. 

Dan

--
. Please pardon any mispelings or errors.


On Dec 24, 2019, at 2:51 PM, Tadd KA2DEW in NC via Groups.Io <tadd@...> wrote:


I wonder if G8BPQ node + TNC-PI can share the i2C bus with the MOPI.


On December 24, 2019 at 1:40 PM, "Tadd KA2DEW in NC via Groups.Io" <tadd@...> wrote:

interesting.  ok.  so same scenario but in B> the Raspberry PI is left OFF.  Does it turn on when G or H?


On December 24, 2019 at 1:36 PM, Daniel Holmes <danielh@...> wrote:

If power is applied to the Pi while it is off it will turn on at G.

Dan
--
Daniel Holmes, danielh@...
"Laugh while you can, monkey boy!" -- Lord John Whorfin


On Dec 24, 2019, at 11:33 AM, Tadd KA2DEW in NC via Groups.Io <tadd@...> wrote:

Using the MOPI-2 In this scenario

A> mains are working.  
B> Start Raspberry PI
C> runs steady for a long time (weeks)
D> Mains go to 0v but are still hooked up.
E> battery eventually gets low
F> MOFI does LInux shutdown and turns off Raspberry PI
G> mains come back eventually
H>  battery charges
J> raspberry is provided power again

Is there a way to have the Raspberry PI come back on-line in H or J ?  

Thanks!
  Tadd - KA2DEW
  Raleigh NC USA


On December 24, 2019 at 11:39 AM, Daniel Holmes <danielh@...> wrote:

Good question on a monitor—I think the specs said it’ll only do about 2.5-3 amps, but there’s a way to switch in a 5V relay to power up the monitor. I personally run my Pi headless, and use VNC on my iPad to connect in (although I have a small wireless keyboard I use because typing on a virtual keyboard stinks.)

Dan
--
Daniel Holmes, danielh@...
"Laugh while you can, monkey boy!" -- Lord John Whorfin


On Dec 24, 2019, at 9:35 AM, Michael WA7SKG <wa7skg@...> wrote:

Dan,

THANK YOU! What a device! While you say expensive, it's only a few dollars more than the USBuddy and does so much more. The on/off switch is a big plus, as well as the HAT configuration. The only thing I'm not sure of is powering the monitor as well. As I am using the Smarti-Pi Touch Case, the RPi is not mounted directly to the monitor, so it is not powered through the IO pins, but from a separate USB connection. However, I do not think this is insurmountable.

Thanks again.

73,
Michael WA7SKG

Daniel Holmes wrote on 12/24/19 6:57 AM:
For running off a 12V supply, this is what I use: https://pi.gate.ac.uk/pages/mopi.html Seems to be pretty RF quiet.
Yeah, it’s a bit expensive, but I have it wired with an on/off switch to power up/power down the Pi cleanly, and it powers it down when the batteries are almost exhausted. I haven’t worked up the battery charger just yet, but it’ll be a handy part of my go-kit. I still need to figure out how to use more than 1 HAT on my Pi, but that’s just a bit of research—so many projects so little time.
Dan












 

I wonder if G8BPQ node + TNC-PI can share the i2C bus with the MOPI.


On December 24, 2019 at 1:40 PM, "Tadd KA2DEW in NC via Groups.Io" <tadd@...> wrote:

interesting.  ok.  so same scenario but in B> the Raspberry PI is left OFF.  Does it turn on when G or H?


On December 24, 2019 at 1:36 PM, Daniel Holmes <danielh@...> wrote:

If power is applied to the Pi while it is off it will turn on at G.

Dan
--
Daniel Holmes, danielh@...
"Laugh while you can, monkey boy!" -- Lord John Whorfin


On Dec 24, 2019, at 11:33 AM, Tadd KA2DEW in NC via Groups.Io <tadd@...> wrote:

Using the MOPI-2 In this scenario

A> mains are working.  
B> Start Raspberry PI
C> runs steady for a long time (weeks)
D> Mains go to 0v but are still hooked up.
E> battery eventually gets low
F> MOFI does LInux shutdown and turns off Raspberry PI
G> mains come back eventually
H>  battery charges
J> raspberry is provided power again

Is there a way to have the Raspberry PI come back on-line in H or J ?  

Thanks!
  Tadd - KA2DEW
  Raleigh NC USA


On December 24, 2019 at 11:39 AM, Daniel Holmes <danielh@...> wrote:

Good question on a monitor—I think the specs said it’ll only do about 2.5-3 amps, but there’s a way to switch in a 5V relay to power up the monitor. I personally run my Pi headless, and use VNC on my iPad to connect in (although I have a small wireless keyboard I use because typing on a virtual keyboard stinks.)

Dan
--
Daniel Holmes, danielh@...
"Laugh while you can, monkey boy!" -- Lord John Whorfin


On Dec 24, 2019, at 9:35 AM, Michael WA7SKG <wa7skg@...> wrote:

Dan,

THANK YOU! What a device! While you say expensive, it's only a few dollars more than the USBuddy and does so much more. The on/off switch is a big plus, as well as the HAT configuration. The only thing I'm not sure of is powering the monitor as well. As I am using the Smarti-Pi Touch Case, the RPi is not mounted directly to the monitor, so it is not powered through the IO pins, but from a separate USB connection. However, I do not think this is insurmountable.

Thanks again.

73,
Michael WA7SKG

Daniel Holmes wrote on 12/24/19 6:57 AM:
For running off a 12V supply, this is what I use: https://pi.gate.ac.uk/pages/mopi.html Seems to be pretty RF quiet.
Yeah, it’s a bit expensive, but I have it wired with an on/off switch to power up/power down the Pi cleanly, and it powers it down when the batteries are almost exhausted. I haven’t worked up the battery charger just yet, but it’ll be a handy part of my go-kit. I still need to figure out how to use more than 1 HAT on my Pi, but that’s just a bit of research—so many projects so little time.
Dan












 

A basic solution would be to just let the mains be online for some period of time before you let the Raspberry PI start.  That period of time could be configured based on charger and battery chemistry I guess.

I'm also interested in it NOT bringing the Raspberry PI up if the last time the operator played with it they left it shutdown.  That would require the charger controller CPU keeping track in RAM or in NVmemory of some kind. 

I made a charge/backup management device with these features but it didn't have provision for an external charger, it only had a trickle for SLA batteries, and it didn't put out enough volts for the Raspberry PI 4.  It used a fixed 5V USB regulator, and worse, it had a USB A socket for a cable to go over to the Raspberry PI.  For a modern Raspberry PI we want 5.1 or so and that voltage AT the Raspberry PI. 
I think PWRMAN has been abandoned because of the low voltage output.  One of the TARPN people was working on a new PCB which was a hat for the Raspberry PI but other things came up. 
 Tadd KA2DEW

On December 24, 2019 at 2:50 PM, David Lane <kg4giy@...> wrote:

By default, yes, once there is enough power, the boot cycle starts. 

Question - how would you retard the boot cycle, until the battery fully charges? Or are you assuming that once the mains are back up, you are ‘good to go,’ and not worried about a secondary outage without enough battery? If the MOPI is managing the battery, does it have the ability to retard that restart?  (I am thinking about the much larger logic circuits that are in smart ups and larger power systems that keep the main CPUs from coming back if the battery charge is still insufficient for full operations and shutdown again - then you get into a is there enough capacity in the capacitor for the battery to know if the capacitor is charged enough to tell the battery to start charging again). Or does it not really matter? (Worse case scenario is a required FSCK on the drive preventing a boot and needing a manual intervention). 

David 



On Dec 24, 2019, at 2:34 PM, Daniel Holmes <danielh@...> wrote:

I don’t have it handy to check, but I’d assume so—anytime you remove power from a Pi and then reapply power it starts up. 

Dan

--
. Please pardon any mispelings or errors.


On Dec 24, 2019, at 11:41 AM, Tadd KA2DEW in NC via Groups.Io <tadd@...> wrote:

interesting.  ok.  so same scenario but in B> the Raspberry PI is left OFF.  Does it turn on when G or H? 


On December 24, 2019 at 1:36 PM, Daniel Holmes <danielh@...> wrote:

If power is applied to the Pi while it is off it will turn on at G.

Dan
--
Daniel Holmes, danielh@...
"Laugh while you can, monkey boy!" -- Lord John Whorfin


On Dec 24, 2019, at 11:33 AM, Tadd KA2DEW in NC via Groups.Io <tadd@...> wrote:

Using the MOPI-2 In this scenario

A> mains are working.   
B> Start Raspberry PI
C> runs steady for a long time (weeks) 
D> Mains go to 0v but are still hooked up.
E> battery eventually gets low
F> MOFI does LInux shutdown and turns off Raspberry PI
G> mains come back eventually
H>  battery charges 
J> raspberry is provided power again 

Is there a way to have the Raspberry PI come back on-line in H or J ?   

Thanks!
  Tadd - KA2DEW 
  Raleigh NC USA


On December 24, 2019 at 11:39 AM, Daniel Holmes <danielh@...> wrote:

Good question on a monitor—I think the specs said it’ll only do about 2.5-3 amps, but there’s a way to switch in a 5V relay to power up the monitor. I personally run my Pi headless, and use VNC on my iPad to connect in (although I have a small wireless keyboard I use because typing on a virtual keyboard stinks.)

Dan
--
Daniel Holmes, danielh@...
"Laugh while you can, monkey boy!" -- Lord John Whorfin


On Dec 24, 2019, at 9:35 AM, Michael WA7SKG <wa7skg@...> wrote:

Dan,

THANK YOU! What a device! While you say expensive, it's only a few dollars more than the USBuddy and does so much more. The on/off switch is a big plus, as well as the HAT configuration. The only thing I'm not sure of is powering the monitor as well. As I am using the Smarti-Pi Touch Case, the RPi is not mounted directly to the monitor, so it is not powered through the IO pins, but from a separate USB connection. However, I do not think this is insurmountable.

Thanks again.

73,
Michael WA7SKG

Daniel Holmes wrote on 12/24/19 6:57 AM:
For running off a 12V supply, this is what I use: https://pi.gate.ac.uk/pages/mopi.html Seems to be pretty RF quiet.
Yeah, it’s a bit expensive, but I have it wired with an on/off switch to power up/power down the Pi cleanly, and it powers it down when the batteries are almost exhausted. I haven’t worked up the battery charger just yet, but it’ll be a handy part of my go-kit. I still need to figure out how to use more than 1 HAT on my Pi, but that’s just a bit of research—so many projects so little time.
Dan













David Lane
 

By default, yes, once there is enough power, the boot cycle starts. 

Question - how would you retard the boot cycle, until the battery fully charges? Or are you assuming that once the mains are back up, you are ‘good to go,’ and not worried about a secondary outage without enough battery? If the MOPI is managing the battery, does it have the ability to retard that restart?  (I am thinking about the much larger logic circuits that are in smart ups and larger power systems that keep the main CPUs from coming back if the battery charge is still insufficient for full operations and shutdown again - then you get into a is there enough capacity in the capacitor for the battery to know if the capacitor is charged enough to tell the battery to start charging again). Or does it not really matter? (Worse case scenario is a required FSCK on the drive preventing a boot and needing a manual intervention). 

David 



On Dec 24, 2019, at 2:34 PM, Daniel Holmes <danielh@...> wrote:

I don’t have it handy to check, but I’d assume so—anytime you remove power from a Pi and then reapply power it starts up. 

Dan

--
. Please pardon any mispelings or errors.


On Dec 24, 2019, at 11:41 AM, Tadd KA2DEW in NC via Groups.Io <tadd@...> wrote:


interesting.  ok.  so same scenario but in B> the Raspberry PI is left OFF.  Does it turn on when G or H? 


On December 24, 2019 at 1:36 PM, Daniel Holmes <danielh@...> wrote:

If power is applied to the Pi while it is off it will turn on at G.

Dan
--
Daniel Holmes, danielh@...
"Laugh while you can, monkey boy!" -- Lord John Whorfin


On Dec 24, 2019, at 11:33 AM, Tadd KA2DEW in NC via Groups.Io <tadd@...> wrote:

Using the MOPI-2 In this scenario

A> mains are working.   
B> Start Raspberry PI
C> runs steady for a long time (weeks) 
D> Mains go to 0v but are still hooked up.
E> battery eventually gets low
F> MOFI does LInux shutdown and turns off Raspberry PI
G> mains come back eventually
H>  battery charges 
J> raspberry is provided power again 

Is there a way to have the Raspberry PI come back on-line in H or J ?   

Thanks!
  Tadd - KA2DEW 
  Raleigh NC USA


On December 24, 2019 at 11:39 AM, Daniel Holmes <danielh@...> wrote:

Good question on a monitor—I think the specs said it’ll only do about 2.5-3 amps, but there’s a way to switch in a 5V relay to power up the monitor. I personally run my Pi headless, and use VNC on my iPad to connect in (although I have a small wireless keyboard I use because typing on a virtual keyboard stinks.)

Dan
--
Daniel Holmes, danielh@...
"Laugh while you can, monkey boy!" -- Lord John Whorfin


On Dec 24, 2019, at 9:35 AM, Michael WA7SKG <wa7skg@...> wrote:

Dan,

THANK YOU! What a device! While you say expensive, it's only a few dollars more than the USBuddy and does so much more. The on/off switch is a big plus, as well as the HAT configuration. The only thing I'm not sure of is powering the monitor as well. As I am using the Smarti-Pi Touch Case, the RPi is not mounted directly to the monitor, so it is not powered through the IO pins, but from a separate USB connection. However, I do not think this is insurmountable.

Thanks again.

73,
Michael WA7SKG

Daniel Holmes wrote on 12/24/19 6:57 AM:
For running off a 12V supply, this is what I use: https://pi.gate.ac.uk/pages/mopi.html Seems to be pretty RF quiet.
Yeah, it’s a bit expensive, but I have it wired with an on/off switch to power up/power down the Pi cleanly, and it powers it down when the batteries are almost exhausted. I haven’t worked up the battery charger just yet, but it’ll be a handy part of my go-kit. I still need to figure out how to use more than 1 HAT on my Pi, but that’s just a bit of research—so many projects so little time.
Dan











Daniel Holmes
 

I don’t have it handy to check, but I’d assume so—anytime you remove power from a Pi and then reapply power it starts up. 

Dan

--
. Please pardon any mispelings or errors.


On Dec 24, 2019, at 11:41 AM, Tadd KA2DEW in NC via Groups.Io <tadd@...> wrote:


interesting.  ok.  so same scenario but in B> the Raspberry PI is left OFF.  Does it turn on when G or H?


On December 24, 2019 at 1:36 PM, Daniel Holmes <danielh@...> wrote:

If power is applied to the Pi while it is off it will turn on at G.

Dan
--
Daniel Holmes, danielh@...
"Laugh while you can, monkey boy!" -- Lord John Whorfin


On Dec 24, 2019, at 11:33 AM, Tadd KA2DEW in NC via Groups.Io <tadd@...> wrote:

Using the MOPI-2 In this scenario

A> mains are working.  
B> Start Raspberry PI
C> runs steady for a long time (weeks)
D> Mains go to 0v but are still hooked up.
E> battery eventually gets low
F> MOFI does LInux shutdown and turns off Raspberry PI
G> mains come back eventually
H>  battery charges
J> raspberry is provided power again

Is there a way to have the Raspberry PI come back on-line in H or J ?  

Thanks!
  Tadd - KA2DEW
  Raleigh NC USA


On December 24, 2019 at 11:39 AM, Daniel Holmes <danielh@...> wrote:

Good question on a monitor—I think the specs said it’ll only do about 2.5-3 amps, but there’s a way to switch in a 5V relay to power up the monitor. I personally run my Pi headless, and use VNC on my iPad to connect in (although I have a small wireless keyboard I use because typing on a virtual keyboard stinks.)

Dan
--
Daniel Holmes, danielh@...
"Laugh while you can, monkey boy!" -- Lord John Whorfin


On Dec 24, 2019, at 9:35 AM, Michael WA7SKG <wa7skg@...> wrote:

Dan,

THANK YOU! What a device! While you say expensive, it's only a few dollars more than the USBuddy and does so much more. The on/off switch is a big plus, as well as the HAT configuration. The only thing I'm not sure of is powering the monitor as well. As I am using the Smarti-Pi Touch Case, the RPi is not mounted directly to the monitor, so it is not powered through the IO pins, but from a separate USB connection. However, I do not think this is insurmountable.

Thanks again.

73,
Michael WA7SKG

Daniel Holmes wrote on 12/24/19 6:57 AM:
For running off a 12V supply, this is what I use: https://pi.gate.ac.uk/pages/mopi.html Seems to be pretty RF quiet.
Yeah, it’s a bit expensive, but I have it wired with an on/off switch to power up/power down the Pi cleanly, and it powers it down when the batteries are almost exhausted. I haven’t worked up the battery charger just yet, but it’ll be a handy part of my go-kit. I still need to figure out how to use more than 1 HAT on my Pi, but that’s just a bit of research—so many projects so little time.
Dan










 

interesting.  ok.  so same scenario but in B> the Raspberry PI is left OFF.  Does it turn on when G or H?


On December 24, 2019 at 1:36 PM, Daniel Holmes <danielh@...> wrote:

If power is applied to the Pi while it is off it will turn on at G.

Dan
--
Daniel Holmes, danielh@...
"Laugh while you can, monkey boy!" -- Lord John Whorfin


On Dec 24, 2019, at 11:33 AM, Tadd KA2DEW in NC via Groups.Io <tadd@...> wrote:

Using the MOPI-2 In this scenario

A> mains are working.  
B> Start Raspberry PI
C> runs steady for a long time (weeks)
D> Mains go to 0v but are still hooked up.
E> battery eventually gets low
F> MOFI does LInux shutdown and turns off Raspberry PI
G> mains come back eventually
H>  battery charges
J> raspberry is provided power again

Is there a way to have the Raspberry PI come back on-line in H or J ?  

Thanks!
  Tadd - KA2DEW
  Raleigh NC USA


On December 24, 2019 at 11:39 AM, Daniel Holmes <danielh@...> wrote:

Good question on a monitor—I think the specs said it’ll only do about 2.5-3 amps, but there’s a way to switch in a 5V relay to power up the monitor. I personally run my Pi headless, and use VNC on my iPad to connect in (although I have a small wireless keyboard I use because typing on a virtual keyboard stinks.)

Dan
--
Daniel Holmes, danielh@...
"Laugh while you can, monkey boy!" -- Lord John Whorfin


On Dec 24, 2019, at 9:35 AM, Michael WA7SKG <wa7skg@...> wrote:

Dan,

THANK YOU! What a device! While you say expensive, it's only a few dollars more than the USBuddy and does so much more. The on/off switch is a big plus, as well as the HAT configuration. The only thing I'm not sure of is powering the monitor as well. As I am using the Smarti-Pi Touch Case, the RPi is not mounted directly to the monitor, so it is not powered through the IO pins, but from a separate USB connection. However, I do not think this is insurmountable.

Thanks again.

73,
Michael WA7SKG

Daniel Holmes wrote on 12/24/19 6:57 AM:
For running off a 12V supply, this is what I use: https://pi.gate.ac.uk/pages/mopi.html Seems to be pretty RF quiet.
Yeah, it’s a bit expensive, but I have it wired with an on/off switch to power up/power down the Pi cleanly, and it powers it down when the batteries are almost exhausted. I haven’t worked up the battery charger just yet, but it’ll be a handy part of my go-kit. I still need to figure out how to use more than 1 HAT on my Pi, but that’s just a bit of research—so many projects so little time.
Dan