Batboard

Does anyone know if it is possible to transmit data using equipment that is on a UHF LTR type trunking system. I have a friend who is self employed, his wife takes calls from their home and he wants to be able receive name address and contact info via the 2 way into his laptop.
So basicly is there a way to do this.

Thanks

Dave

Yes,

The thing you need, a device that takes digital data, turns it into analog, a MODulator, takes analog, turns it into digital, DEModulator.

MODEM

Actually, a Terminal Node Controller makes it easier, but almost every modem I have come across, can run burst mode with S/W, both driver and app' .

Thank You.

You can use radio-modem like the Télédesign TS-2000.

OK, I am not real familiar with TNC's. This is what Hams use for Packet right? Will 2 TNC's send data back and forth to each other without connecting through a node?
I think I am referring to everything correctly.
The TNC's connect to the RCV and XMT audio and PTT correct? Being able to use the 2 way for voice communication is a must.
This would be transparent to the trunking system also right?
Does anyone know of any links where I could find out more about using TNC's

Thanks very much

Dave

Hello.

The average computer laptop modem, running 9600 baud, half-duplex, can connect to a radio, simple interface box for mic', speaker.
The software and drivers allow for no handshaking.
A TNC, with the correct S/W, will allow semi-transparent operation, that is to say, you do not have to listen to modem noise, do not have to switch modes, but you do have to wait for path to clear, usually a light will flicker, somthing to tell you the computer is linking.
Do not try to send anything but simple, short, text, the link is very slow, tying the channel up with data prevents voice, but for everyone.

TNX.

Don't tell CDPD is the only way to have decent/web surfing type speeds.. (I wouldn't even classify it as that fast) I saw the wa4dsy 56K modem, I want to get 20 miles omni-direction with something in the Ks (would settle for 14.4, but of course 56K+ would be great) I just want to link my van/mobile workshop to my base. Any ideas, cause I know I'm not paying for CDPD for more a less a toy or convenience.

OK guys I am catching on. I checked with Ham Radio Outlet. They have TNC modems. But they aren't sure if they will go one on one, They are sure of the price though.

Cow Theif,

Are you talking about the regular Data/Fax modem that is used to connect via dialup? besides setting it up for half duplex, how do the modems sync up with each other? And how would I control the PTT lead? Do the modems just go into a receive mode and not look for handshaking that normally happens when a connection is made?

Thanks all for the info.

Dave

YES a tnc will go radio to radio!

both radios must have a tnc on them.

you do NOT need a node to go through.

a standard tnc is a 1200 baud (bps) modem.

newer 9600 baud labeled tnc's are a 9600 baud modem.

you may want to check out hamfest's or swap meets etc as the 1200 baud tnc's are usually quite cheap.

if you want to buy new, keep in mind that some tnc's will decode morse code and weather sat's as well as many other "data" modes.


the short tnc data that you are talking about should not tie up the channel too long - and there is software and settings for shared voice and data.

there is a company that makes a product called a "rig blaster" that interfaces a sound card to a radio for "data" types - and mfj also makes data radios which are tnc's and that operate on a xtal controlled freq.

also check out the tigertronics web site they make the baypac and telem. encoders/decoders.

Bill

calif dave wrote:OK guys I am catching on. I checked with Ham Radio Outlet. They have TNC modems. But they aren't sure if they will go one on one, They are sure of the price though.

Cow Theif,

Are you talking about the regular Data/Fax modem that is used to connect via dialup? besides setting it up for half duplex, how do the modems sync up with each other? And how would I control the PTT lead? Do the modems just go into a receive mode and not look for handshaking that normally happens when a connection is made?

Thanks all for the info.

Dave

The RTX-12 Radio Modem looks like it will do what I am looking for and at the right price. I found it at tigertronics.com (thanks Bill).

I am still interested in using a regular dial up modem to send half duplex also.

Thanks

Dave

Hello.

Some TNCs, like the glenayre, allow for full auto operation, that is to say, you leave the mic in the holder, when you remove it, it goes into voice mode. return it, it's back to data, no buttons.
The laptop modem can control a PTT line easily, this is done with a box that looks at the loop status, to key, it will close the loop.
Audio needs to be split, this is done with a dual op-amp chip in my unit, but this is no where near automatic, you have to listen to the radio, voice and data.
I have a setup that uses CTCSS/PL to open the speaker for voice, indicator lamp for data, but I am not running trunking, might not be able to send CTCSS over trunking, remember, the signalling format of trunking.

Thank You.