Ham radio pocsag

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WX5812

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I know there is pocsag on pistar. Is there a program that works on windows that will encode pocsag? I’d like to set it up where I can send an email and somehow the software transmit the email to a pocsag pager. Curious to hear some of yalls ideas and what y’all have going on with pocsag.
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a417

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I’d like to set it up where I can send an email and somehow the software transmit the email to a pocsag pager.
So you want to make a pocsag gateway? Would you be providing the transmitter as well, or do you want to be able to just send an email and get it over the air via someone else's hardware?
 

WX5812

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Yes I have a transmitter and a sound card interface. Several vhf radios to choose from and a RA25 interface.
 

ramal121

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Yes I have a transmitter and a sound card interface. Several vhf radios to choose from and a RA25 interface.

That's not going to work. Pocsag needs a data stream injected direct to the modulator of the transmitter. Usually they use RS-232. A sound card just won't cut it. Also you need a true FM transmitter, not PM, for any kind of reliability.
 

WX5812

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This isn’t for a commercial application, just for fun. I’ve seen on YouTube where a few guys have a Motorola vhf radio as there transmitter and the software itself generates the bursts. So 100% reliability isn’t necessary. Just tying in the software to an email address is what I don’t get how to do.
 

a417

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Yes, that will give you a GNU soft block for pocsag, but GNURadio has an extremely steep learning curve ... and tying it into hardware for transmit takes a fair amount of work.

"...here be Dragons."
 

Project4

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In the early 2000's I wrote a Visual Basic application that resulted in alphanumeric pages over the air. The software was in two parts. The "client" user interface was where one composed their message and chose the pager(s) recipients. A short text string was assembled containing the message, addressee common name, message priority and time stamp. That text was sent over a network and written to a common file residing on the "server". The client-server model was utilized to accommodate multiple remote client terminals. The server software prioritized unsent messages, located the recipient pager's address in a table and formatted and sent a command string to the paging hardware. It also logged the transactions. The paging hardware consisted of the Kantronics 9612 "Packet Communicator" connected to a Kenwood TK-780 transceiver. The Kantronics modem receives commands via a serial port and generates POCSAG tone data for transmission.

I think it would be relatively simple to parse an inbound email into the segments needed to format a page command for a hardware modem like the Kantronics 9612. Using a soundcard or other software modem is more of a challenge.
 

WX5812

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Very interesting, I see the Kantronics tnc’s are not a bad price wise on eBay.. leaving the windows version alone, this program gascop that uses the raspberry pi has some pretty good instructions and it does a lot. Would it need a tnc as well or does the software send the needed bursts straight to the radio?
This may be the route I go
 

Project4

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Very interesting, I see the Kantronics tnc’s are not a bad price wise on eBay.. leaving the windows version alone, this program gascop that uses the raspberry pi has some pretty good instructions and it does a lot. Would it need a tnc as well or does the software send the needed bursts straight to the radio?
This may be the route I go
Just below halfway down the Gascop webpage (Gascop pocsag paging system) there is a description of the hardware interface between the raspberry pi and a radio transmitter "mod". I believe "mod" refers to the appropriate modulation injection point on the transmitter circuit board. You would not need the Kantronics 9612 modem in that application.
 

WX5812

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In the early 2000's I wrote a Visual Basic application that resulted in alphanumeric pages over the air. The software was in two parts. The "client" user interface was where one composed their message and chose the pager(s) recipients. A short text string was assembled containing the message, addressee common name, message priority and time stamp. That text was sent over a network and written to a common file residing on the "server". The client-server model was utilized to accommodate multiple remote client terminals. The server software prioritized unsent messages, located the recipient pager's address in a table and formatted and sent a command string to the paging hardware. It also logged the transactions. The paging hardware consisted of the Kantronics 9612 "Packet Communicator" connected to a Kenwood TK-780 transceiver. The Kantronics modem receives commands via a serial port and generates POCSAG tone data for transmission.

I think it would be relatively simple to parse an inbound email into the segments needed to format a page command for a hardware modem like the Kantronics 9612. Using a soundcard or other software modem is more of a challenge.
Is a Kantronics 9612 the only model tnc that will work in a paging operation?
 

Project4

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Is a Kantronics 9612 the only model tnc that will work in a paging operation?
The Zetron Model 61 is a commercial unit but similar in function. MAXPage makes desktop terminals with RS-232 inputs. These have integrated radio transmitters. There may be others, likely more expensive than an eBay Kantronics. My only experience is with the 9612.
 

ramal121

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OK, sorry, was assuming a ham rig. Yes Motorolas work. I've seen pocsag encoders hooked to GM300's before.

However again, the sound card will NEVER work. Pocsag is not an AFSK mode.
 

Project4

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OK, sorry, was assuming a ham rig. Yes Motorolas work. I've seen pocsag encoders hooked to GM300's before.

However again, the sound card will NEVER work. Pocsag is not an AFSK mode.
To clarify. The data signal needs to be injected directly into the FM modulator, not the microphone jack on the front of a radio. Typically, that is after the microphone pre-amp and audio equalization stages of your transmitter.
 

WX5812

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To clarify. The data signal needs to be injected directly into the FM modulator, not the microphone jack on the front of a radio. Typically, that is after the microphone pre-amp and audio equalization stages of your transmitter.
Yes, if I’m not mistaken, the flat tx audio on Motorola’s is just that. (I could be wrong but that’s been my thought for quite a while).. the same goes for the din connectors on some radios for packet use
 
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