Simplex Repeater Question

[WRPR796]

So does anybody have any information resources about using a KG905 radio and something that is not raspberry Pi based to build a simplex repeater, I'm trying to figure out a way to improve my radio connectivity in my semi without just loading an app on a smart phone, where's the fun in that. While it's not shtf reliable, it should be a learning experience that might develop some skills / knowledge that might be useful for another project someday.

Thanks

[WRPR796]

Ps I'm not married to the kg905 yet, I just don't really want to use a bowfang, yeah yeah I have no idea how that's really spelled

Thanks

[WRPR796]

There are probably radios better suited for this type of project too, but I'm well above my pay grade at the moment

[axorlov]

I have Argent Data SR1 simplex repeater. I use it occasionally, when deep in the woods. I connect it to my TK-880H in the SUV, with self-fabricated cable. Argent Data has schematics for the repeater and for cable connector, so if you know few things about electronics, putting together a cable for any radio is fairly trivial.

Repeater is programmed to listen and stay silent, and repeat only when it hears DTMF "0". Combined with efficient antenna on a tall flat roof of SUV, it greatly improves range of our HTs. Especially, if SUV is parked at a good high spot. The operation goes like this: when far from campsite hiking I call the family and give them some time to answer (about 1 min). If they can hear and answer me, fine. If they do not, I send DTMF "0" from my HT. Repeater hears it and repeats the last transmission with all its mighty 40W. If I hear this repeat, I know for sure that family also heard it. If I do not hear repeat, I know that I'm out of range and need to find higher ground to be heard.

SR1 can be programmed to parrot every transmission, but that's extremely annoying, and gets long real quick.

Also, simplex repeater seems to be in conflict with store-forward prohibition on GMRS, but it sort of not fully clear to me.

[WRPR796]

1 hour ago, axorlov said:

I have Argent Data SR1 simplex repeater. I use it occasionally, when deep in the woods. I connect it to my TK-880H in the SUV, with self-fabricated cable. Argent Data has schematics for the repeater and for cable connector, so if you know few things about electronics, putting together a cable for any radio is fairly trivial.

Repeater is programmed to listen and stay silent, and repeat only when it hears DTMF "0". Combined with efficient antenna on a tall flat roof of SUV, it greatly improves range of our HTs. Especially, if SUV is parked at a good high spot. The operation goes like this: when far from campsite hiking I call the family and give them some time to answer (about 1 min). If they can hear and answer me, fine. If they do not, I send DTMF "0" from my HT. Repeater hears it and repeats the last transmission with all its mighty 40W. If I hear this repeat, I know for sure that family also heard it. If I do not hear repeat, I know that I'm out of range and need to find higher ground to be heard.

SR1 can be programmed to parrot every transmission, but that's extremely annoying, and gets long real quick.

Also, simplex repeater seems to be in conflict with store-forward prohibition on GMRS, but it sort of not fully clear to me.

Thanks,

After reading your description of operation, perhaps I'm using the term "simplex repeater" wrong!

I don't think what I'm trying to build is a "cross band repeater" either.

I actually see it, based on past computer network terminology as a "Bridge" in so much as it is bridging two disparate systems, ie.. radio system bridged to internet and vice versa.

The plot thickens

 

[SteveShannon]

1 hour ago, WRPR796 said:

Thanks,

After reading your description of operation, perhaps I'm using the term "simplex repeater" wrong!

I don't think what I'm trying to build is a "cross band repeater" either.

I actually see it, based on past computer network terminology as a "Bridge" in so much as it is bridging two disparate systems, ie.. radio system bridged to internet and vice versa.

The plot thickens

 

So I think what you’re trying to do is have some kind of simple Raspberry Pi device that listens to gmrs and ties it to a network on the internet?

I have no knowledge of that for GMRS, but I’ve done similar things with a Pi hat for digital mode ham radio so I’ll follow along. 

[WRPR796]

1 hour ago, Sshannon said:

So I think what you’re trying to do is have some kind of simple Raspberry Pi device that listens to gmrs and ties it to a network on the internet?

I have no knowledge of that for GMRS, but I’ve done similar things with a Pi hat for digital mode ham radio so I’ll follow along. 

Sshannon yes I am trying to bridge the radio to the internet, and vice versa, but I am also trying to avoid the Pi due to it's unavailability I would also like to avoid the Baufang radios also, I have seen mobile radios that have some sort of access port (Motorola) I have to believe that would be the best case scenario

Thanks

[axorlov]

Yeah, you threw me off with "simplex repeater". This term has a meaning.

But asterisk software does not have run on Pi. Any Linux will do. Old laptop should do just fine. Beaglebone boards are still available on amazon and elsewhere.

[SteveShannon]

1 hour ago, WRPR796 said:

Sshannon yes I am trying to bridge the radio to the internet, and vice versa, but I am also trying to avoid the Pi due to it's unavailability I would also like to avoid the Baufang radios also, I have seen mobile radios that have some sort of access port (Motorola) I have to believe that would be the best case scenario

Thanks

https://www.orionsystemsinc.net/radio-over-ip-roip-device/

[WRPR796]

6 minutes ago, Sshannon said:

https://www.orionsystemsinc.net/radio-over-ip-roip-device/

  Thank you that looks like exactly what I was thinking of!!

[SteveShannon]

15 minutes ago, WRPR796 said:

  Thank you that looks like exactly what I was thinking of!!

I have no experience with this. I put together a pi device.

There are other devices made for Echolink or Allstar that might be okay also. 

[WROZ250]

Sounds like what you are looking for is some kind of 'hot spot'. 

I think a bigger issue you might be running into is finding a GMRS network that will accept a non-repeater (i.e. Hot Spot) connecting to their network.  Many, including the MyGMRS network only allow repeaters to connect.

That said, I do know such system are out there because You Tube has all sorts of videos with people building these things.  Unfortunately most of these are running asterisk (a.k.a A-star or Allstar) or some variation of it on a RPi.  Really disgusting how much the price of the RPi has gone up.  

I could be wrong, but I believe there is a version of asterisk that will run under Linux on a PC.

Good Luck in any event.

[wrci350]

On 4/30/2022 at 3:00 PM, WROZ250 said:

 Really disgusting how much the price of the RPi has gone up.  

I could be wrong, but I believe there is a version of asterisk that will run under Linux on a PC.
 

The official price for Raspberry Pi boards has not gone up one cent.  Unfortunately, like many other things, they are in short supply due to the ongoing chip shortage and other logistical challenges.  There are people out there that are buying them (usually in quantity) from an authorized reseller when they are available and turning around and selling them at rip-off prices.  Many of the legit resellers are taking measures to prevent that from happening, but they are still very hard to locate.

And yes, Asterisk (including the Allstar flavor) will run on a PC running Linux.

[Radioguy7268]

17 hours ago, wrci350 said:

The official price for Raspberry Pi boards has not gone up one cent.  Unfortunately, like many other things, they are in short supply due to the ongoing chip shortage and other logistical challenges.  There are people out there that are buying them (usually in quantity) from an authorized reseller when they are available and turning around and selling them at rip-off prices.  Many of the legit resellers are taking measures to prevent that from happening, but they are still very hard to locate.

And yes, Asterisk (including the Allstar flavor) will run on a PC running Linux.

I must have missed the part where a willing buyer and a willing seller are involved in a transaction that becomes a rip-off.  If someone is willing to buy something that's a price 3 times above what it 'normally' sells for - then that person is signalling to the market that there is a shortage of the product, and that there is an opportunity awaiting those who can fill the gap.

That's economics 101.

People make noise about price gouging and rip-offs. Pricing to the market is what every enterprising businessperson does - or they go out of business.  If you're a consumer who pays 3 times the 'normal' price for the product, you either have a compelling reason for buying it, or you're plain nuts. Wait out that temporary price increase if you feel that the market will correct, or search for alternative products that meet your need at a price that's more appealing.

[WROZ250]

In this case it is (IMHO) a ripoff.  Raspberry Pi in the UK, still shows the device (as @wrci350 points out) with a specific MSRP.  It is the resellers that have jacked up their prices to close to 400% in some cases, and in doing so have created the shortage.

At the same time, @Radioguy7268, you are correct in that there is nothing wrong with doing that (legally).

To that point, by doing this, these retailers have taken an otherwise affordable product, targeting hobbyists, and put it financially out of reach of many of those same hobbyists.  In the end, 'Economics 101' is probably going to come back and bite these hording, profit taking, retailers in their proverbial asses as sales will drop.  This will happened because those targeted hobbyists will look to other options, and so by the time this BS crisis ends, interest in the Raspberry Pi line will have evaporated.

In many ways I blame the Raspberry Pi Organization itself. 

If they really believe their product should retail for under $100, then why don't they sell it directly at that price to end users?  

Indeed, selling it only through retailers who are clearly capitalizing on a bad situation, kinda of makes them look as guilty as their 'authorized retailers'.  If they were genuinely honest, they would either (as many manufacturers do) restrict the 'Authorized retailer" to a fixed price.  If it was costing them more to make the product, they why not be honest and raise the MSRP to what they believe it should be.

The bottom line is at that the Raspberry Pi is no longer an affordable alternative to, for example, a Linux PC (other than size perhaps) and, there are other (previously less popular) small board computers on the market that aren't selling at 400% over MSRP.

So if the Raspberry Pi organization doesn't take control over its 'authorized retailers', then they are only hurting themselves in the long run.

Yet another great idea ruined by greed.

Just one opinion...

[wrci350]

It's not the authorized resellers that are doing this, so don't blame them.  They are still selling them for the official price.  Check a few of their websites and you'll see that's the case.

These are people who are buying RPis from the authorized resellers (at the MSRP) and turning around and offering them at jacked-up prices.  Is that illegal?  No.  Is it unethical?  I would argue that it is, especially when these folks are using things like bots that monitor the authorized reseller websites and as soon as there are any RPis available they buy 100 or 1000.  I don't think many hobbyists have those resources available to them.  That's why many (hopefully all) of the resellers have taken measures to prevent this.

Here's the word from Raspberry Pi:

https://www.raspberrypi.com/news/production-and-supply-chain-update/

I didn't mean to take us off into a discussion on the ethics of the free market.  Personally I find it disturbing that I can't just order a couple RPis any time I want like I could a year or so ago.  Fortunately I have a small stockpile (we're talking 3 or 4, not 3 or 4 hundred!) that I can use for any projects I am working on.  I might even be willing to part with one or two.  $1500 sounds like a good starting bid.  

[WROZ250]

1 hour ago, wrci350 said:

It's not the authorized resellers that are doing this, so don't blame them.  They are still selling them for the official price.  Check a few of their websites and you'll see that's the case.

These are people who are buying RPis from the authorized resellers (at the MSRP) and turning around and offering them at jacked-up prices.  Is that illegal?  No.  Is it unethical?  I would argue that it is, especially when these folks are using things like bots that monitor the authorized reseller websites and as soon as there are any RPis available they buy 100 or 1000.  I don't think many hobbyists have those resources available to them.  That's why many (hopefully all) of the resellers have taken measures to prevent this.

Here's the word from Raspberry Pi:

https://www.raspberrypi.com/news/production-and-supply-chain-update/

I didn't mean to take us off into a discussion on the ethics of the free market.  Personally I find it disturbing that I can't just order a couple RPis any time I want like I could a year or so ago.  Fortunately I have a small stockpile (we're talking 3 or 4, not 3 or 4 hundred!) that I can use for any projects I am working on.  I might even be willing to part with one or two.  $1500 sounds like a good starting bid.  

Well, that sort of makes @Radioguy7268 case.  If somebody is willing to pay a 3rd party 400% over retail, then they kind of deserve to get fleeced.  Still, I don't see the 'authorized retailers' selling at MSRP, so they too are profiting to some extent.  You are correct however, It isn't illegal, but it is horribly unethical.

Either way it's a bad situation. 

While I don't have a stockpile, I do have enough for the projects I am working on and, while I would have liked to have had a few more in hand, I simply cannot justify paying even the best prices today.  Given that, I have been looking at other SBC options if not reusing an older PC with Linux OS.

I too apologize for the off track pull on the thread.

[wrci350]

1 hour ago, WROZ250 said:

Still, I don't see the 'authorized retailers' selling at MSRP, so they too are profiting to some extent.  You are correct however, It isn't illegal, but it is horribly unethical.

@WROZ250 I'm curious which authorized resellers have raised the prices.  I just checked all the ones I've purchased from (Adafruit, Sparkfun, Pishop.US, The Pi Hut) and of course none of them HAVE any RPIs, but they are still showing the MSRP.  Interestingly enough, I also checked Mouser and Digikey and while Digikey's prices seem to match MSRP, Mouser's are higher, but only by a few bucks, not double or anything like that.

One thing to note is that Amazon is NOT an authorized reseller.  If you had looked on Amazon for RPIs a year or two ago, you would have found lots of accessories but no actual boards.  Now, you can find LOTS of boards for sale, at tremendously inflated prices.  How about an RPi 3B+, which should cost $35, for $239???   I think I'll pass, thanks.  But if you look at the listings, they aren't actually being sold by Amazon.  The order might ship from an Amazon warehouse, but it's a third-party seller.  At lot of them don't even ship from Amazon but directly from the seller.

[MichaelLAX]

On 5/3/2022 at 4:57 AM, Radioguy7268 said:

I must have missed the part where a willing buyer and a willing seller are involved in a transaction that becomes a rip-off.  If someone is willing to buy something that's a price 3 times above what it 'normally' sells for - then that person is signalling to the market that there is a shortage of the product, and that there is an opportunity awaiting those who can fill the gap.

That's economics 101.

People make noise about price gouging and rip-offs. Pricing to the market is what every enterprising businessperson does - or they go out of business.  If you're a consumer who pays 3 times the 'normal' price for the product, you either have a compelling reason for buying it, or you're plain nuts. Wait out that temporary price increase if you feel that the market will correct, or search for alternative products that meet your need at a price that's more appealing.

Many states have laws against gouging essential items when there are shortages.  I don't think a Raspberry Pi qualifies as essential.

[lazarus1024]

On 4/29/2022 at 2:51 PM, axorlov said:

I have Argent Data SR1 simplex repeater. I use it occasionally, when deep in the woods. I connect it to my TK-880H in the SUV, with self-fabricated cable. Argent Data has schematics for the repeater and for cable connector, so if you know few things about electronics, putting together a cable for any radio is fairly trivial.

Repeater is programmed to listen and stay silent, and repeat only when it hears DTMF "0". Combined with efficient antenna on a tall flat roof of SUV, it greatly improves range of our HTs. Especially, if SUV is parked at a good high spot. The operation goes like this: when far from campsite hiking I call the family and give them some time to answer (about 1 min). If they can hear and answer me, fine. If they do not, I send DTMF "0" from my HT. Repeater hears it and repeats the last transmission with all its mighty 40W. If I hear this repeat, I know for sure that family also heard it. If I do not hear repeat, I know that I'm out of range and need to find higher ground to be heard.

SR1 can be programmed to parrot every transmission, but that's extremely annoying, and gets long real quick.

Also, simplex repeater seems to be in conflict with store-forward prohibition on GMRS, but it sort of not fully clear to me.

Interesting on your use. I just posted a review of the ADS SR-1 that I picked up a few days ago. I am loving it. Great for testing radio equipment without annoying my wife or kids to help out. Plus in my neighborhood terrain can create a problem for talking to each other on HTs for things like trick or treating (and there are actually a couple of spots cell phones have no reception). My house being up on one of the low ridge lines should help. I haven't tested it yet, but having a high gain antenna 15ft above the ground, on a ridge that is about 20-30ft above the "valleys" next to it, and likely much easier to "see" in to valleys 2 or 3 or 4 ridges and a mile over, vs trying to reach another HT in a valley a mile and several ridges away.

At least my prior experience with H777s (lower radio power and lower antenna gain) was from far to far there would be little to no reception. My UV-9g and Nagoya 771g is working with at least 3dB higher receive and 5dB higher transmit between the additional antenna gain as well as the extra radio power. But that may not still be enough over the longer ranges if both HTs are in separate "valleys" a good distance away. Even setting my base station to low power (~5w) to match the HTs, the antenna being much higher above the average local terrain, as well as being a 6dBi antenna gains an additional 3dB advantage, plus the much higher height to reduce terrain interference.

 

Anyway, I can see how simplex repeaters can be annoying. I have it setup so that the HTs can use a repeater channel with PL code to talk to the ADS SR-1 equipped radio, which will listen on the higher repeater channel and then broadcast on the lower channel that the HTs are set to listen to. So no one is hearing the same broadcast twice. It makes conversations take longer, but it avoids that additional annoyance of "gee, did anyone hear me?" wait a minute or two to see if anyone responds and if no one does, then activate the repeater to rebroadcast at that point. So I think I'd rather it parrot every transmission, than set it to only repeat on command. If everything was set to a simplex channel, then yeah, I'd rather only trigger it to broadcast on command.

 

I am probably going to pickup a 2nd ADS SR-1 so I can run it as a radio in an ammo can portable repeater. Just for fun. Then use this first one for my house base station as a repeater. Or since I have the same radio in my car, it makes it easy to take along if I want or need to setup my car GMRS radio as a repeater for HTs. I am also (at some point, if my wife ever figures out what is happening to my kids play set that is sitting on my trailer) turning a trailer in to a tear drop camper. The repeater can also come along with the radio I plan to put in the camper (use an extendable pole as an antenna mast so I can get something medium gain, 4.2-6dBi, up about 12-15ft off the ground).

 

On the OPs original question, I am very interested. Out of curiosity, OP, are you looking for do something like radio to text? Radio to VOIP?

[WRPR796]

On 5/5/2022 at 10:47 AM, lazarus1024 said:

On the OPs original question, I am very interested. Out of curiosity, OP, are you looking for do something like radio to text? Radio to VOIP?

Thanks for taking time to read and respond, I'm just looking for a solution to increase my overall connectivity in my semi truck as I travel randomly all over the lower 48.

I do think the proper term is Radio to VOIP, or Roip, not completely sure.

I do believe I inadvertently misused the term "Simplex Repeater" and probably confused the issue in so doing.

There are some rasberry Pi based solutions to accomplish what I'm trying to do. But apparently the are some political issues with those solutions here on this network so this may well be a lost cause for the time being.

I believe there are other solutions that would accomplish the goal also, it will be a learning curve for me and there are still the political problems that are completely beyond my control.

I won't say its impossible, but probably unfeasible for now.

[WRKC935]

Since this got pretty well hi-jacked pertaining to the R-Pi and the current cost and availability, I will throw this in. 

I am interested to see what may replace the Pi as the standard for the 'maker space' and other DIY development efforts.

There are a number of SBC's (single board computers) filling that space that may be a bit more expensive, but in some cases are FAR more capable.

And I have had mixed results with the Pi.  For development and experimentation the Pi is a good platform.  But for production gear, I prefer the Beagle Bone. 

Same numbers as the Pi performance wise, but they just seem to be more stable.  And depending on how stable I want it, I am not above loading Buster (Debian Linux that the R-Pi OS is based on) on a VM instance and running it all in a VM container.  Recovery with snapshots is very quick and you can do a recovery remotely, where a memory card failure at a remote site requires a trip there.