Topics

Noisy Pi4 - particularly on 2m


Steve
 

Setting up for this evenings 2m UKAC I noticed the noise floor was around S8. The obvious suspect being the recentle added Pi. It was!
Not helped by the fact I have it in a perspex case. It's also very close to the rig
The plan is to put it in a metal case and do the same with the power supply - although I might also change that for a
https://uk.farnell.com/tracopower/txm-015-105/power-supply-ac-dc-15w-5v-3a/dp/2363846
Which are made to a slightly higher standard than the wall worts (or is it wart?) that are everywhere.
Thoughts on the above - please - alternative suggestions.
73's
Steve

G4SDM


Charles Rich AK4SR
 

Wall warts are often a big contributor to noise. The good news is that even though the makers of the Raspberry Pi don't recommend connecting it to the USB port on your computer, it actually works just fine (depending on the reliability of your computer, of course). Cutting the power supply out altogether is definitely a less noisy way to operate.

The biggest reason the Pi guys say not to plug into the USB is mostly because computers are often set to put USB ports to sleep when the computer screen blanks and that can shut down the Pi unexpectedly. Set your computer and ports to never sleep and you're good to go. I've also heard the argument that USB ports don't provide enough current - but then the wall wart that comes with the Pi isn't capable of putting out as much current as a USB 3 port (where's the logic in that?). 

Charles
AK4SR
https://stemhamradio.net

On 6/2/2020 12:43 PM, Steve wrote:

Setting up for this evenings 2m UKAC I noticed the noise floor was around S8. The obvious suspect being the recentle added Pi. It was!
Not helped by the fact I have it in a perspex case. It's also very close to the rig
The plan is to put it in a metal case and do the same with the power supply - although I might also change that for a
https://uk.farnell.com/tracopower/txm-015-105/power-supply-ac-dc-15w-5v-3a/dp/2363846
Which are made to a slightly higher standard than the wall worts (or is it wart?) that are everywhere.
Thoughts on the above - please - alternative suggestions.
73's
Steve

G4SDM



Clark Martin
 

A simple, possible, fix is to wrap any cables around a ferrite toroid (one per cable) as close to the Pi as you can.  Also wrap the power cord around one as close as possible to the wall wart.  That is two ferrites , one at each end.You may not need to shield it if you can prevent the cabling from being antennas. 

Clark Martin

KK6ISP

Yet another designated driver on the information super highway.


On Jun 2, 2020, at 10:59 AM, Steve <steve@...> wrote:



Setting up for this evenings 2m UKAC I noticed the noise floor was around S8. The obvious suspect being the recentle added Pi. It was!
Not helped by the fact I have it in a perspex case. It's also very close to the rig
The plan is to put it in a metal case and do the same with the power supply - although I might also change that for a
https://uk.farnell.com/tracopower/txm-015-105/power-supply-ac-dc-15w-5v-3a/dp/2363846
Which are made to a slightly higher standard than the wall worts (or is it wart?) that are everywhere.
Thoughts on the above - please - alternative suggestions.
73's
Steve

G4SDM


Brian Webster
 

I have heard that the HDMI on a Pi can cause a lot of noise. Try running headless if you can and see if the noise problem goes away.

 

Brian N2KGC

 

From: RaspberryPi-4-HamRadio@groups.io [mailto:RaspberryPi-4-HamRadio@groups.io] On Behalf Of Clark Martin
Sent: Tuesday, June 2, 2020 4:00 PM
To: RaspberryPi-4-HamRadio@groups.io
Subject: Re: [RaspberryPi-4-HamRadio] Noisy Pi4 - particularly on 2m

 

A simple, possible, fix is to wrap any cables around a ferrite toroid (one per cable) as close to the Pi as you can.  Also wrap the power cord around one as close as possible to the wall wart.  That is two ferrites , one at each end.You may not need to shield it if you can prevent the cabling from being antennas. 

Clark Martin

KK6ISP

Yet another designated driver on the information super highway.



On Jun 2, 2020, at 10:59 AM, Steve <steve@...> wrote:



Setting up for this evenings 2m UKAC I noticed the noise floor was around S8. The obvious suspect being the recentle added Pi. It was!
Not helped by the fact I have it in a perspex case. It's also very close to the rig
The plan is to put it in a metal case and do the same with the power supply - although I might also change that for a
https://uk.farnell.com/tracopower/txm-015-105/power-supply-ac-dc-15w-5v-3a/dp/2363846
Which are made to a slightly higher standard than the wall worts (or is it wart?) that are everywhere.
Thoughts on the above - please - alternative suggestions.
73's
Steve

G4SDM


 

We have found that placing the board and any HATs in a faraday cage (metal case) solves on board problems.


nb7o
 

Another solution, that I use here, is to buy a dc-dc voltage converter.  I have a 12v to 5v dc-dc converter with a usb connector on the 5v side.  I have Anderson power poles on the 12v side and I plug it into my 50a 12v power supply.  The DC-DC converter I have provides 3a of power to the PI which also helps with low voltage conditions on the pi.

 

Seven three de kevin/NB7O


Chuck M
 

I've done that as well.  On pi3 tweaked the voltage until lightning icon stayed home.

Thingiverse has various case designs for them depending on model.  Also designs to make inline fuse holder.

Can also get something like this:

KD9DVB


On Tue, Jun 2, 2020 at 7:34 PM, nb7o
<khedgepe@...> wrote:

Another solution, that I use here, is to buy a dc-dc voltage converter.  I have a 12v to 5v dc-dc converter with a usb connector on the 5v side.  I have Anderson power poles on the 12v side and I plug it into my 50a 12v power supply.  The DC-DC converter I have provides 3a of power to the PI which also helps with low voltage conditions on the pi.

 

Seven three de kevin/NB7O


 

What we need is a 9 V to 15 V DC input device which outputs 5.1v regulated to a USB socket and which delivers that voltage reliably automatically when the input voltage is applied (not like the new DROK device which requires menu manipulation to turn on the USB output).  Most of the devices that are close to these specs only put out 4.9 to 5 V which is not enough for the PI 4B.  Or, they use screw terminal outputs which is not good for the casual Raspberry PI software engineer.  Sockets are good.  
We’d further like this device to be $20 or less.  I’ve seen things which are really close to what we want for as little as a couple of dollars.  But close doesn’t count here.  It has to be 5.1 VDC and it has to be always on, and it has to take DC input.  

Would it be worth $40 to have a 3 Amp linear supply through-hole KIT that does the above?  I have a schematic for a circuit to do this and handle charging, switchover, and relay protect for a GelCel UPS and early protection alert to Raspberry PI when the battery is getting close to damaging itself.  WN8P did the schematic.  We’re pondering making and selling PCBs (for cost via ETSY) and publishing a bill-of-materials for builder purchase from DigiKey.  

The design seems expensive.  I’m just wondering if it is worth it.  The cost includes the heat sync but no housing or Gel Cel.   Dunno.  It seemed a good idea at the time.  I can do really good kit building instructions. See this page: 


  KA2DEW

On Jun 2, 2020, at 8:33 PM, Chuck M via groups.io <cam51mail@...> wrote:

I've done that as well.  On pi3 tweaked the voltage until lightning icon stayed home.

Thingiverse has various case designs for them depending on model.  Also designs to make inline fuse holder.

Can also get something like this:

KD9DVB


On Tue, Jun 2, 2020 at 7:34 PM, nb7o
<khedgepe@...> wrote:

Another solution, that I use here, is to buy a dc-dc voltage converter.  I have a 12v to 5v dc-dc converter with a usb connector on the 5v side.  I have Anderson power poles on the 12v side and I plug it into my 50a 12v power supply.  The DC-DC converter I have provides 3a of power to the PI which also helps with low voltage conditions on the pi.

 

Seven three de kevin/NB7O



N3RDR
 

Curious. How about a small battery pack that provides the required output and is kept charged via not so ideal chargers? Is battery life even a concern in that scenario?

Carlos
N3RDR

Sent from my 📲

On Jun 3, 2020, at 1:23 PM, Tadd KA2DEW in NC via groups.io <tadd@...> wrote:

What we need is a 9 V to 15 V DC input device which outputs 5.1v regulated to a USB socket and which delivers that voltage reliably automatically when the input voltage is applied (not like the new DROK device which requires menu manipulation to turn on the USB output).  Most of the devices that are close to these specs only put out 4.9 to 5 V which is not enough for the PI 4B.  Or, they use screw terminal outputs which is not good for the casual Raspberry PI software engineer.  Sockets are good.  
We’d further like this device to be $20 or less.  I’ve seen things which are really close to what we want for as little as a couple of dollars.  But close doesn’t count here.  It has to be 5.1 VDC and it has to be always on, and it has to take DC input.  

Would it be worth $40 to have a 3 Amp linear supply through-hole KIT that does the above?  I have a schematic for a circuit to do this and handle charging, switchover, and relay protect for a GelCel UPS and early protection alert to Raspberry PI when the battery is getting close to damaging itself.  WN8P did the schematic.  We’re pondering making and selling PCBs (for cost via ETSY) and publishing a bill-of-materials for builder purchase from DigiKey.  

The design seems expensive.  I’m just wondering if it is worth it.  The cost includes the heat sync but no housing or Gel Cel.   Dunno.  It seemed a good idea at the time.  I can do really good kit building instructions. See this page: 


  KA2DEW

On Jun 2, 2020, at 8:33 PM, Chuck M via groups.io <cam51mail@...> wrote:

I've done that as well.  On pi3 tweaked the voltage until lightning icon stayed home.

Thingiverse has various case designs for them depending on model.  Also designs to make inline fuse holder.

Can also get something like this:

KD9DVB


On Tue, Jun 2, 2020 at 7:34 PM, nb7o
<khedgepe@...> wrote:

Another solution, that I use here, is to buy a dc-dc voltage converter.  I have a 12v to 5v dc-dc converter with a usb connector on the 5v side.  I have Anderson power poles on the 12v side and I plug it into my 50a 12v power supply.  The DC-DC converter I have provides 3a of power to the PI which also helps with low voltage conditions on the pi.

 

Seven three de kevin/NB7O



Mark Griffith
 

There are lots of these modules around, some are better than others.  I have used some that output 5.15 volts consistently, and some just 5.0 volts.  Some have two micro USB connectors, some do not.  I have a few of these I use now that are very reliable.  eBay is a good place to find them.

I guess for $13 you get some and see what happens.  You can also afford to get a few as backups in case of failure.

In my shack, I use a West Mountain Radio PG40S power gate which takes 15 volts from an old Radio Shack analog power supply, and outputs about 14.8 volts to a Anderson Power Pole power block, and keeps a Type 27 deep cycle battery charged.  From the power block I use a few of these DC-DC step down modules to convert to 5.1 volts.  I have the same setup at my home (shack is in a different location) with a smaller battery to power the PiGate development devices and a radio.  If the power fails, the battery is switched in instantly and give me enough power to supply my PiGate RMS station for a day or so, or my home development site for about 12 hours.

There are lots of solutions.  Experiment!

Mark
KD0QYN



 



On Wednesday, June 3, 2020, 12:29:02 PM CDT, Tadd KA2DEW in NC via groups.io <tadd@...> wrote:


What we need is a 9 V to 15 V DC input device which outputs 5.1v regulated to a USB socket and which delivers that voltage reliably automatically when the input voltage is applied (not like the new DROK device which requires menu manipulation to turn on the USB output).  Most of the devices that are close to these specs only put out 4.9 to 5 V which is not enough for the PI 4B.  Or, they use screw terminal outputs which is not good for the casual Raspberry PI software engineer.  Sockets are good.  
We’d further like this device to be $20 or less.  I’ve seen things which are really close to what we want for as little as a couple of dollars.  But close doesn’t count here.  It has to be 5.1 VDC and it has to be always on, and it has to take DC input.  

Would it be worth $40 to have a 3 Amp linear supply through-hole KIT that does the above?  I have a schematic for a circuit to do this and handle charging, switchover, and relay protect for a GelCel UPS and early protection alert to Raspberry PI when the battery is getting close to damaging itself.  WN8P did the schematic.  We’re pondering making and selling PCBs (for cost via ETSY) and publishing a bill-of-materials for builder purchase from DigiKey.  

The design seems expensive.  I’m just wondering if it is worth it.  The cost includes the heat sync but no housing or Gel Cel.   Dunno.  It seemed a good idea at the time.  I can do really good kit building instructions. See this page: 


  KA2DEW

On Jun 2, 2020, at 8:33 PM, Chuck M via groups.io <cam51mail@...> wrote:

I've done that as well.  On pi3 tweaked the voltage until lightning icon stayed home.

Thingiverse has various case designs for them depending on model.  Also designs to make inline fuse holder.

Can also get something like this:

KD9DVB


On Tue, Jun 2, 2020 at 7:34 PM, nb7o
<khedgepe@...> wrote:

Another solution, that I use here, is to buy a dc-dc voltage converter.  I have a 12v to 5v dc-dc converter with a usb connector on the 5v side.  I have Anderson power poles on the 12v side and I plug it into my 50a 12v power supply.  The DC-DC converter I have provides 3a of power to the PI which also helps with low voltage conditions on the pi.

 

Seven three de kevin/NB7O



 

The wet mount radio power gate costs $140??  
And I thought $40 was high. And the battery protection and charge is just one minor feature of the $40 project. 
$13 EACH to try some and see what happens.  Hmm..   

What I’m hearing is that there isn’t really a product out there that gives us the 5.1v from 12v every time one is bought and tried.  
The little wall wart thing for the Raspberry PI 4 is a good thing, but it has the wrong voltage input and no battery backup. 


On Jun 3, 2020, at 2:26 PM, Mark Griffith via groups.io <mdgriffith2003@...> wrote:

There are lots of these modules around, some are better than others.  I have used some that output 5.15 volts consistently, and some just 5.0 volts.  Some have two micro USB connectors, some do not.  I have a few of these I use now that are very reliable.  eBay is a good place to find them.

I guess for $13 you get some and see what happens.  You can also afford to get a few as backups in case of failure.

In my shack, I use a West Mountain Radio PG40S power gate which takes 15 volts from an old Radio Shack analog power supply, and outputs about 14.8 volts to a Anderson Power Pole power block, and keeps a Type 27 deep cycle battery charged.  From the power block I use a few of these DC-DC step down modules to convert to 5.1 volts.  I have the same setup at my home (shack is in a different location) with a smaller battery to power the PiGate development devices and a radio.  If the power fails, the battery is switched in instantly and give me enough power to supply my PiGate RMS station for a day or so, or my home development site for about 12 hours.

There are lots of solutions.  Experiment!

Mark
KD0QYN



 



On Wednesday, June 3, 2020, 12:29:02 PM CDT, Tadd KA2DEW in NC via groups.io <tadd@...> wrote:


What we need is a 9 V to 15 V DC input device which outputs 5.1v regulated to a USB socket and which delivers that voltage reliably automatically when the input voltage is applied (not like the new DROK device which requires menu manipulation to turn on the USB output).  Most of the devices that are close to these specs only put out 4.9 to 5 V which is not enough for the PI 4B.  Or, they use screw terminal outputs which is not good for the casual Raspberry PI software engineer.  Sockets are good.  
We’d further like this device to be $20 or less.  I’ve seen things which are really close to what we want for as little as a couple of dollars.  But close doesn’t count here.  It has to be 5.1 VDC and it has to be always on, and it has to take DC input.  

Would it be worth $40 to have a 3 Amp linear supply through-hole KIT that does the above?  I have a schematic for a circuit to do this and handle charging, switchover, and relay protect for a GelCel UPS and early protection alert to Raspberry PI when the battery is getting close to damaging itself.  WN8P did the schematic.  We’re pondering making and selling PCBs (for cost via ETSY) and publishing a bill-of-materials for builder purchase from DigiKey.  

The design seems expensive.  I’m just wondering if it is worth it.  The cost includes the heat sync but no housing or Gel Cel.   Dunno.  It seemed a good idea at the time.  I can do really good kit building instructions. See this page: 


  KA2DEW

On Jun 2, 2020, at 8:33 PM, Chuck M via groups.io <cam51mail@...> wrote:

I've done that as well.  On pi3 tweaked the voltage until lightning icon stayed home.

Thingiverse has various case designs for them depending on model.  Also designs to make inline fuse holder.

Can also get something like this:

KD9DVB


On Tue, Jun 2, 2020 at 7:34 PM, nb7o
<khedgepe@...> wrote:

Another solution, that I use here, is to buy a dc-dc voltage converter.  I have a 12v to 5v dc-dc converter with a usb connector on the 5v side.  I have Anderson power poles on the 12v side and I plug it into my 50a 12v power supply.  The DC-DC converter I have provides 3a of power to the PI which also helps with low voltage conditions on the pi.

 

Seven three de kevin/NB7O




Hank Riley
 

Mark,

Could you please provide a link or two just to give us a clue about what you're talking about specifically ?  There are so many devices on Ebay it would be really helpful to narrow it down.

Hank
_________________________________________________________

On Jun 3, 2020, at 2:26 PM, Mark Griffith wrote:

There are lots of these modules around, some are better than others.  I have used some that output 5.15 volts consistently, and some just 5.0 volts.  Some have two micro USB connectors, some do not.  I have a few of these I use now that are very reliable.  eBay is a good place to find them.

I guess for $13 you get some and see what happens.  


Jim Lange
 

I got a few adjustable dc-dc converters for my pi’s. I feed them with 13.8 volts and adjust them for 5.1 volts out then solder them to the 5 volt pins on the pi. Not elegant due to soldering direct to the pi and having an outboard converter flopping about. I let my shack or repeater site ac/dc switching worry about the 13.8 volt part. 

For my use a dc/dc converter hat that would fit between the pi and whatever else I was using would be ideal. 

Wouldn’t make a difference to me if the input was solder tabs, screw terminals or some kind of connector that wouldn’t pull apart easily. 


Sent by me


On Jun 3, 2020, at 14:30, Tadd KA2DEW in NC via groups.io <tadd@...> wrote:

The wet mount radio power gate costs $140??  
And I thought $40 was high. And the battery protection and charge is just one minor feature of the $40 project. 
$13 EACH to try some and see what happens.  Hmm..   

What I’m hearing is that there isn’t really a product out there that gives us the 5.1v from 12v every time one is bought and tried.  
The little wall wart thing for the Raspberry PI 4 is a good thing, but it has the wrong voltage input and no battery backup. 


On Jun 3, 2020, at 2:26 PM, Mark Griffith via groups.io <mdgriffith2003@...> wrote:

There are lots of these modules around, some are better than others.  I have used some that output 5.15 volts consistently, and some just 5.0 volts.  Some have two micro USB connectors, some do not.  I have a few of these I use now that are very reliable.  eBay is a good place to find them.

I guess for $13 you get some and see what happens.  You can also afford to get a few as backups in case of failure.

In my shack, I use a West Mountain Radio PG40S power gate which takes 15 volts from an old Radio Shack analog power supply, and outputs about 14.8 volts to a Anderson Power Pole power block, and keeps a Type 27 deep cycle battery charged.  From the power block I use a few of these DC-DC step down modules to convert to 5.1 volts.  I have the same setup at my home (shack is in a different location) with a smaller battery to power the PiGate development devices and a radio.  If the power fails, the battery is switched in instantly and give me enough power to supply my PiGate RMS station for a day or so, or my home development site for about 12 hours.

There are lots of solutions.  Experiment!

Mark
KD0QYN



 



On Wednesday, June 3, 2020, 12:29:02 PM CDT, Tadd KA2DEW in NC via groups.io <tadd@...> wrote:


What we need is a 9 V to 15 V DC input device which outputs 5.1v regulated to a USB socket and which delivers that voltage reliably automatically when the input voltage is applied (not like the new DROK device which requires menu manipulation to turn on the USB output).  Most of the devices that are close to these specs only put out 4.9 to 5 V which is not enough for the PI 4B.  Or, they use screw terminal outputs which is not good for the casual Raspberry PI software engineer.  Sockets are good.  
We’d further like this device to be $20 or less.  I’ve seen things which are really close to what we want for as little as a couple of dollars.  But close doesn’t count here.  It has to be 5.1 VDC and it has to be always on, and it has to take DC input.  

Would it be worth $40 to have a 3 Amp linear supply through-hole KIT that does the above?  I have a schematic for a circuit to do this and handle charging, switchover, and relay protect for a GelCel UPS and early protection alert to Raspberry PI when the battery is getting close to damaging itself.  WN8P did the schematic.  We’re pondering making and selling PCBs (for cost via ETSY) and publishing a bill-of-materials for builder purchase from DigiKey.  

The design seems expensive.  I’m just wondering if it is worth it.  The cost includes the heat sync but no housing or Gel Cel.   Dunno.  It seemed a good idea at the time.  I can do really good kit building instructions. See this page: 


  KA2DEW

On Jun 2, 2020, at 8:33 PM, Chuck M via groups.io <cam51mail@...> wrote:

I've done that as well.  On pi3 tweaked the voltage until lightning icon stayed home.

Thingiverse has various case designs for them depending on model.  Also designs to make inline fuse holder.

Can also get something like this:

KD9DVB


On Tue, Jun 2, 2020 at 7:34 PM, nb7o
<khedgepe@...> wrote:

Another solution, that I use here, is to buy a dc-dc voltage converter.  I have a 12v to 5v dc-dc converter with a usb connector on the 5v side.  I have Anderson power poles on the 12v side and I plug it into my 50a 12v power supply.  The DC-DC converter I have provides 3a of power to the PI which also helps with low voltage conditions on the pi.

 

Seven three de kevin/NB7O




Mark Griffith
 

If you want battery backup, you need to have some sort of charger to manage the battery.  This is much more than just providing 12v power.  The PWRGate switches instantly from the power supply to the battery, not causing a Raspberry Pi reboot.  This is the most important thing to me to prevent premature SD card failure.

You can also try putting a battery maintainer as sold in Walmart and other stores that supply 1.5A at 12VDC, and attach that to a battery, and then your 12VDC to microUSB power module.  This works, I have done it in the past, but they are not very good at keeping the battery charged AND supply power to a Raspberry Pi and radio.  The battery eventually looses its charge and you don't find out about it until the power fails and your Raspberry Pis go down.  The PWRGate integrates all the parts.

You are, of course, free to design your own.  There are lots of plans online for voltage converters.

Mark
KD0QYN


On Wednesday, June 3, 2020, 1:30:46 PM CDT, Tadd KA2DEW in NC via groups.io <tadd@...> wrote:


The wet mount radio power gate costs $140??  
And I thought $40 was high. And the battery protection and charge is just one minor feature of the $40 project. 
$13 EACH to try some and see what happens.  Hmm..   

What I’m hearing is that there isn’t really a product out there that gives us the 5.1v from 12v every time one is bought and tried.  
The little wall wart thing for the Raspberry PI 4 is a good thing, but it has the wrong voltage input and no battery backup. 


On Jun 3, 2020, at 2:26 PM, Mark Griffith via groups.io <mdgriffith2003@...> wrote:

There are lots of these modules around, some are better than others.  I have used some that output 5.15 volts consistently, and some just 5.0 volts.  Some have two micro USB connectors, some do not.  I have a few of these I use now that are very reliable.  eBay is a good place to find them.

I guess for $13 you get some and see what happens.  You can also afford to get a few as backups in case of failure.

In my shack, I use a West Mountain Radio PG40S power gate which takes 15 volts from an old Radio Shack analog power supply, and outputs about 14.8 volts to a Anderson Power Pole power block, and keeps a Type 27 deep cycle battery charged.  From the power block I use a few of these DC-DC step down modules to convert to 5.1 volts.  I have the same setup at my home (shack is in a different location) with a smaller battery to power the PiGate development devices and a radio.  If the power fails, the battery is switched in instantly and give me enough power to supply my PiGate RMS station for a day or so, or my home development site for about 12 hours.

There are lots of solutions.  Experiment!

Mark
KD0QYN



 



On Wednesday, June 3, 2020, 12:29:02 PM CDT, Tadd KA2DEW in NC via groups.io <tadd@...> wrote:


What we need is a 9 V to 15 V DC input device which outputs 5.1v regulated to a USB socket and which delivers that voltage reliably automatically when the input voltage is applied (not like the new DROK device which requires menu manipulation to turn on the USB output).  Most of the devices that are close to these specs only put out 4.9 to 5 V which is not enough for the PI 4B.  Or, they use screw terminal outputs which is not good for the casual Raspberry PI software engineer.  Sockets are good.  
We’d further like this device to be $20 or less.  I’ve seen things which are really close to what we want for as little as a couple of dollars.  But close doesn’t count here.  It has to be 5.1 VDC and it has to be always on, and it has to take DC input.  

Would it be worth $40 to have a 3 Amp linear supply through-hole KIT that does the above?  I have a schematic for a circuit to do this and handle charging, switchover, and relay protect for a GelCel UPS and early protection alert to Raspberry PI when the battery is getting close to damaging itself.  WN8P did the schematic.  We’re pondering making and selling PCBs (for cost via ETSY) and publishing a bill-of-materials for builder purchase from DigiKey.  

The design seems expensive.  I’m just wondering if it is worth it.  The cost includes the heat sync but no housing or Gel Cel.   Dunno.  It seemed a good idea at the time.  I can do really good kit building instructions. See this page: 


  KA2DEW

On Jun 2, 2020, at 8:33 PM, Chuck M via groups.io <cam51mail@...> wrote:

I've done that as well.  On pi3 tweaked the voltage until lightning icon stayed home.

Thingiverse has various case designs for them depending on model.  Also designs to make inline fuse holder.

Can also get something like this:

KD9DVB


On Tue, Jun 2, 2020 at 7:34 PM, nb7o
<khedgepe@...> wrote:

Another solution, that I use here, is to buy a dc-dc voltage converter.  I have a 12v to 5v dc-dc converter with a usb connector on the 5v side.  I have Anderson power poles on the 12v side and I plug it into my 50a 12v power supply.  The DC-DC converter I have provides 3a of power to the PI which also helps with low voltage conditions on the pi.

 

Seven three de kevin/NB7O




 

Indeed.  $140 is a non-starter.  
It would be idea to be able to fully discharge the battery once in a while with a constant current load while watching the voltage.  This could give us the true capacity.  However..  For $3 worth of parts we can float a gel-cel across a 13.7v supply through a 47 ohm 10watt resistor and that does the job within the Gel Cel survival tolerances specified by the UPS manufacturers, i.e. about 3 years to replacement.  The real value in the $140 device is that it saves the Gel Cel from damage as it passes through the not-recoverable-voltage.  But we can do that with a zener diode, a transistor and a relay.  What we’d really like is two Zener diodes where the higher voltage one would be used to send a logic signal to the Raspberry PI telling it that it is in danger of losing power soon.  I don’t think the $140 device does that.  But we can make a circuit that does, put all fo the switchover and charging parts along with the zeners, relay and whatnot onto a PCB for about $15.  
now.. toss in a DC in 5.1v DC out 3amp regulator with a USB-A socket and we have a real product.  $140?  How about if we sell the PCB for cost and let the operator build the kit from Digikey purchased parts?  $40.  There you go.  My thought processes in a nutshell.  

   Tadd - KA2DEW


On Jun 3, 2020, at 3:15 PM, Mark Griffith via groups.io <mdgriffith2003@...> wrote:

If you want battery backup, you need to have some sort of charger to manage the battery.  This is much more than just providing 12v power.  The PWRGate switches instantly from the power supply to the battery, not causing a Raspberry Pi reboot.  This is the most important thing to me to prevent premature SD card failure.

You can also try putting a battery maintainer as sold in Walmart and other stores that supply 1.5A at 12VDC, and attach that to a battery, and then your 12VDC to microUSB power module.  This works, I have done it in the past, but they are not very good at keeping the battery charged AND supply power to a Raspberry Pi and radio.  The battery eventually looses its charge and you don't find out about it until the power fails and your Raspberry Pis go down.  The PWRGate integrates all the parts.

You are, of course, free to design your own.  There are lots of plans online for voltage converters.

Mark
KD0QYN


On Wednesday, June 3, 2020, 1:30:46 PM CDT, Tadd KA2DEW in NC via groups.io <tadd@...> wrote:


The wet mount radio power gate costs $140??  
And I thought $40 was high. And the battery protection and charge is just one minor feature of the $40 project. 
$13 EACH to try some and see what happens.  Hmm..   

What I’m hearing is that there isn’t really a product out there that gives us the 5.1v from 12v every time one is bought and tried.  
The little wall wart thing for the Raspberry PI 4 is a good thing, but it has the wrong voltage input and no battery backup. 


On Jun 3, 2020, at 2:26 PM, Mark Griffith via groups.io <mdgriffith2003@...> wrote:

There are lots of these modules around, some are better than others.  I have used some that output 5.15 volts consistently, and some just 5.0 volts.  Some have two micro USB connectors, some do not.  I have a few of these I use now that are very reliable.  eBay is a good place to find them.

I guess for $13 you get some and see what happens.  You can also afford to get a few as backups in case of failure.

In my shack, I use a West Mountain Radio PG40S power gate which takes 15 volts from an old Radio Shack analog power supply, and outputs about 14.8 volts to a Anderson Power Pole power block, and keeps a Type 27 deep cycle battery charged.  From the power block I use a few of these DC-DC step down modules to convert to 5.1 volts.  I have the same setup at my home (shack is in a different location) with a smaller battery to power the PiGate development devices and a radio.  If the power fails, the battery is switched in instantly and give me enough power to supply my PiGate RMS station for a day or so, or my home development site for about 12 hours.

There are lots of solutions.  Experiment!

Mark
KD0QYN



 



On Wednesday, June 3, 2020, 12:29:02 PM CDT, Tadd KA2DEW in NC via groups.io <tadd@...> wrote:


What we need is a 9 V to 15 V DC input device which outputs 5.1v regulated to a USB socket and which delivers that voltage reliably automatically when the input voltage is applied (not like the new DROK device which requires menu manipulation to turn on the USB output).  Most of the devices that are close to these specs only put out 4.9 to 5 V which is not enough for the PI 4B.  Or, they use screw terminal outputs which is not good for the casual Raspberry PI software engineer.  Sockets are good.  
We’d further like this device to be $20 or less.  I’ve seen things which are really close to what we want for as little as a couple of dollars.  But close doesn’t count here.  It has to be 5.1 VDC and it has to be always on, and it has to take DC input.  

Would it be worth $40 to have a 3 Amp linear supply through-hole KIT that does the above?  I have a schematic for a circuit to do this and handle charging, switchover, and relay protect for a GelCel UPS and early protection alert to Raspberry PI when the battery is getting close to damaging itself.  WN8P did the schematic.  We’re pondering making and selling PCBs (for cost via ETSY) and publishing a bill-of-materials for builder purchase from DigiKey.  

The design seems expensive.  I’m just wondering if it is worth it.  The cost includes the heat sync but no housing or Gel Cel.   Dunno.  It seemed a good idea at the time.  I can do really good kit building instructions. See this page: 


  KA2DEW

On Jun 2, 2020, at 8:33 PM, Chuck M via groups.io <cam51mail@...> wrote:

I've done that as well.  On pi3 tweaked the voltage until lightning icon stayed home.

Thingiverse has various case designs for them depending on model.  Also designs to make inline fuse holder.

Can also get something like this:

KD9DVB


On Tue, Jun 2, 2020 at 7:34 PM, nb7o
<khedgepe@...> wrote:

Another solution, that I use here, is to buy a dc-dc voltage converter.  I have a 12v to 5v dc-dc converter with a usb connector on the 5v side.  I have Anderson power poles on the 12v side and I plug it into my 50a 12v power supply.  The DC-DC converter I have provides 3a of power to the PI which also helps with low voltage conditions on the pi.

 

Seven three de kevin/NB7O





Siegfried Jackstien
 

i had good results for anything that needs 5v with these black power modules

https://www.ebay.de/itm/DC-DC-12V-to-5V-3A-Step-Down-Converter-Power-Supply-Module-Micro-USB-Waterproof/272608334734?hash=item3f78b9138e:g:~HAAAOSw2gxY2hy3

they can be found with open end wires or with usb connector (different versions)

greetz sigi dg9bfc

Am 03.06.2020 um 19:08 schrieb Hank Riley via groups.io:

Mark,

Could you please provide a link or two just to give us a clue about what you're talking about specifically ?  There are so many devices on Ebay it would be really helpful to narrow it down.

Hank
_________________________________________________________

On Jun 3, 2020, at 2:26 PM, Mark Griffith wrote:

There are lots of these modules around, some are better than others.  I have used some that output 5.15 volts consistently, and some just 5.0 volts.  Some have two micro USB connectors, some do not.  I have a few of these I use now that are very reliable.  eBay is a good place to find them.

I guess for $13 you get some and see what happens.  


Mark Griffith
 

Right, the CPT modules work pretty good.

Mark
KD0QYN

On Wednesday, June 3, 2020, 2:25:19 PM CDT, Siegfried Jackstien <siegfried.jackstien@...> wrote:


i had good results for anything that needs 5v with these black power modules

https://www.ebay.de/itm/DC-DC-12V-to-5V-3A-Step-Down-Converter-Power-Supply-Module-Micro-USB-Waterproof/272608334734?hash=item3f78b9138e:g:~HAAAOSw2gxY2hy3

they can be found with open end wires or with usb connector (different versions)

greetz sigi dg9bfc

Am 03.06.2020 um 19:08 schrieb Hank Riley via groups.io:
Mark,

Could you please provide a link or two just to give us a clue about what you're talking about specifically ?  There are so many devices on Ebay it would be really helpful to narrow it down.

Hank
_________________________________________________________

On Jun 3, 2020, at 2:26 PM, Mark Griffith wrote:

There are lots of these modules around, some are better than others.  I have used some that output 5.15 volts consistently, and some just 5.0 volts.  Some have two micro USB connectors, some do not.  I have a few of these I use now that are very reliable.  eBay is a good place to find them.

I guess for $13 you get some and see what happens.  


 

Alas they do not do what the Raspberry PI 4B calls for. 
So far I’ve not had one go wrong for 5v needs. 


On Jun 3, 2020, at 3:22 PM, Siegfried Jackstien <siegfried.jackstien@...> wrote:

i had good results for anything that needs 5v with these black power modules

https://www.ebay.de/itm/DC-DC-12V-to-5V-3A-Step-Down-Converter-Power-Supply-Module-Micro-USB-Waterproof/272608334734?hash=item3f78b9138e:g:~HAAAOSw2gxY2hy3

they can be found with open end wires or with usb connector (different versions)

greetz sigi dg9bfc

Am 03.06.2020 um 19:08 schrieb Hank Riley via groups.io:
Mark,

Could you please provide a link or two just to give us a clue about what you're talking about specifically ?  There are so many devices on Ebay it would be really helpful to narrow it down.

Hank
_________________________________________________________

On Jun 3, 2020, at 2:26 PM, Mark Griffith wrote:

There are lots of these modules around, some are better than others.  I have used some that output 5.15 volts consistently, and some just 5.0 volts.  Some have two micro USB connectors, some do not.  I have a few of these I use now that are very reliable.  eBay is a good place to find them.

I guess for $13 you get some and see what happens.  


nb7o
 

Here is a link to the 12v to 5v converters that I use.  I like the water resistant varieties.  I use them on our boat for navigation computer on a pi.

 

 

This converter terminates in a USB jack on the 5v side.

https://smile.amazon.com/HOMREE-Converter-Voltage-Regulator-Standard/dp/B01MEF293V

 

This converter terminates in a micro-usb jack on the 5v side and professes to be waterproof.  I merely hope for resistant.

https://smile.amazon.com/Converter-Regulator-Waterproof-Converters-Smartphone/dp/B07H7X37T6

 

 

seven three de Kevin/NB7O

 


Mark Griffith
 

They are definitely all not equal.  I have one now running a 4B with no under voltage alerts for months.

There are lots of little, cheap, USB voltage and current monitors that are available.  Plug your module into it and then from the monitor to the Pi and you can see the voltage and current draw.  I use it to check 5V supplies, and some will show 5.2 or 5.24 volts, and some show 5.0, or 4.98.  You take what you get.  The 5.2 volt outputs work great for all the Raspberry Pi models.

Search on eBay for "Multifunction USB Tester"

Mark
KD0QYN


On Wednesday, June 3, 2020, 2:45:46 PM CDT, Tadd KA2DEW in NC via groups.io <tadd@...> wrote:


Alas they do not do what the Raspberry PI 4B calls for. 
So far I’ve not had one go wrong for 5v needs. 


On Jun 3, 2020, at 3:22 PM, Siegfried Jackstien <siegfried.jackstien@...> wrote:

i had good results for anything that needs 5v with these black power modules

https://www.ebay.de/itm/DC-DC-12V-to-5V-3A-Step-Down-Converter-Power-Supply-Module-Micro-USB-Waterproof/272608334734?hash=item3f78b9138e:g:~HAAAOSw2gxY2hy3

they can be found with open end wires or with usb connector (different versions)

greetz sigi dg9bfc

Am 03.06.2020 um 19:08 schrieb Hank Riley via groups.io:
Mark,

Could you please provide a link or two just to give us a clue about what you're talking about specifically ?  There are so many devices on Ebay it would be really helpful to narrow it down.

Hank
_________________________________________________________

On Jun 3, 2020, at 2:26 PM, Mark Griffith wrote:

There are lots of these modules around, some are better than others.  I have used some that output 5.15 volts consistently, and some just 5.0 volts.  Some have two micro USB connectors, some do not.  I have a few of these I use now that are very reliable.  eBay is a good place to find them.

I guess for $13 you get some and see what happens.