Using a VHF radio to send and receive data
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Hi, i want some advice, i want to send and receive data with an VHF conventional radio,·1200bps max, using a pair of BS2SX, i think i need a UART?, can recomend me one?
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>Hi, i want some advice, i want to send and receive data with an VHF
>conventional radio, 1200bps max, using a pair of BS2SX, i think i need a
>UART?, can recomend me one?
Hi Gabriel -
If this is for low power FM you may want to take a look at the Parallax RF
App Mod kits.
You needn't buy the kit to view the documentation which is found in the
DOWNLOAD
Section of their website [noparse][[/noparse] http://www.parallaxinc.com ]. There are two
files which may be of interest:
RF Modules Manual (.pdf)
RF Modules Source Code (.zip)
Hope that gets you started.
Regards,
Bruce Bates
Try a TNC. (Terminal Node Controller,. which is a geeky name for a modem that can be hooked to a radio) we in the Amateur Radio world use them A LOT. 1200bps, connects to PTT, audio out and audio in on the radio. Very simple
There are several manufacturers
try doing a serach for AMATEUR RADIO TNC
or visit PacComm http://www.paccomm.com/main.html#Amateur
PS getting a HAM RADIO License is easier than ever and there are all kinds off cool things to do·
check out www.arrl.org for more info
regards
Brian
n8pqi@pobox.com
Original Message
From: Gabriel Rivero
To: basicstamps@egroups.com
Sent: Thursday, November 02, 2000 12:50 AM
Subject: [noparse][[/noparse]basicstamps] Using a VHF radio to send and receive data
Hi, i want some advice, i want to send and receive data with an VHF conventional radio,·1200bps max, using a pair of BS2SX, i think i need a UART?, can recomend me one?
Tom Churchill
Brian McClure wrote:
Original Message
From:Gabriel Rivero
To: basicstamps@egroups.com
Sent: Thursday, November 02, 200012:50 AM
Subject: [noparse][[/noparse]basicstamps] Using a VHFradio to send and receive data
·[size=-1]Hi, i want some advice, i want tosend and receive data with an VHF conventional radio, 1200bps max, usinga pair of BS2SX, i think i need a UART?, can recomend me one?[/size]
> send and receive data with an VHF
> conventional radio, 1200bps max,
> using a pair of BS2SX, i think i
> need a UART?, can recomend me one?
A UART won't do the job by itself. In fact, its not strictly
necessary for this application if you are bit-banging your own serial
data direct from the stamp.
The real issue with sending over a radio is converting digital
signals to audio tones, just like sending data over a phone line.
There are numerous commercial products for doing this, usually
controllable over RS-232 serial. If you want a commercial product,
you'll want a "TNC" as alluded to by another poster. Kantronics is my
personal favorite. Note that you don't need a FCC license to purchase
or operate a TNC as such, just to transmit over most radio bands. Be
sure you know the rules before you start transmitting.
Parallax, of course, distributes its own line of short-range
transceivers as well, as do a couple other vendors.
If you want to "Do It Yourself", you'll need a modem chip. This is a
device which converts serial data to/from audio tones. For 1200 baud,
a straightforward Bell modem emulator is preferred. Higher baudrates
require more exotic encoding schemes. 9600 baud over VHF and higher
frequencies is being done, but is not yet common. (Rule of thumb: the
higher the frequency, the higher the theoretical baudrate limit.)
MX-COM produces a Bell modem chip called the MX-614 which is
suitable. You should check out the PIC-Encoder project of TAPR, a
group for amateur data radio enthusiasts. PIC-E is their attempt to
create a low-cost, customizable TNC built around a PIC.
http://www.tapr.org If nothing else, you can purchase the 614 chip
direct from them; it is rather difficult to find in small quantities
elsewhere.
--- Kevin
Baudrate directly translates into the width of the transmitted signal.
Typically, 9600 baud is the practical limit of VHF and most UHF
frequencies, using standard modulation techniques. Actually, FCC
regulations prohibit higher datarates than this for this very reason.
If you want mega data rates, consider 2 gigs and up.
Ken
At 12:03 AM 12/1/00 -0000, you wrote:
>> Hi, i want some advice, i want to
>> send and receive data with an VHF
>> conventional radio, 1200bps max,
>> using a pair of BS2SX, i think i
>> need a UART?, can recomend me one?
>
>A UART won't do the job by itself. In fact, its not strictly
>necessary for this application if you are bit-banging your own serial
>data direct from the stamp.
>
>The real issue with sending over a radio is converting digital
>signals to audio tones, just like sending data over a phone line.
>There are numerous commercial products for doing this, usually
>controllable over RS-232 serial. If you want a commercial product,
>you'll want a "TNC" as alluded to by another poster. Kantronics is my
>personal favorite. Note that you don't need a FCC license to purchase
>or operate a TNC as such, just to transmit over most radio bands. Be
>sure you know the rules before you start transmitting.
>
>Parallax, of course, distributes its own line of short-range
>transceivers as well, as do a couple other vendors.
>
>If you want to "Do It Yourself", you'll need a modem chip. This is a
>device which converts serial data to/from audio tones. For 1200 baud,
>a straightforward Bell modem emulator is preferred. Higher baudrates
>require more exotic encoding schemes. 9600 baud over VHF and higher
>frequencies is being done, but is not yet common. (Rule of thumb: the
>higher the frequency, the higher the theoretical baudrate limit.)
>
>MX-COM produces a Bell modem chip called the MX-614 which is
>suitable. You should check out the PIC-Encoder project of TAPR, a
>group for amateur data radio enthusiasts. PIC-E is their attempt to
>create a low-cost, customizable TNC built around a PIC.
>http://www.tapr.org If nothing else, you can purchase the 614 chip
>direct from them; it is rather difficult to find in small quantities
>elsewhere.
>
>--- Kevin
>
>
>
>
>
>
Ken Arck
http://www.ah6le.net
Amateur Radio Station AH6LE
[url=palace://stables.xsia.com:9998]palace://stables.xsia.com:9998[/url]
aka Ph's horse
I played around using an old baby monitor and transmitter, using dtmf
and a holtek dtmf receiver I was able to transmit and receive very
nicely also very slowly and this is most likely against FCC regs also
! but if your looking at getting data from one place to another over
rf slow and cheep this is it.
Ken Arck wrote:
>
> I have one comment to add to this..
>
> Baudrate directly translates into the width of the transmitted signal.
> Typically, 9600 baud is the practical limit of VHF and most UHF
> frequencies, using standard modulation techniques. Actually, FCC
> regulations prohibit higher datarates than this for this very reason.
>
> If you want mega data rates, consider 2 gigs and up.
>
> Ken
>
> At 12:03 AM 12/1/00 -0000, you wrote:
> >> Hi, i want some advice, i want to
> >> send and receive data with an VHF
> >> conventional radio, 1200bps max,
> >> using a pair of BS2SX, i think i
> >> need a UART?, can recomend me one?
> >
> >A UART won't do the job by itself. In fact, its not strictly
> >necessary for this application if you are bit-banging your own serial
> >data direct from the stamp.
> >
> >The real issue with sending over a radio is converting digital
> >signals to audio tones, just like sending data over a phone line.
> >There are numerous commercial products for doing this, usually
> >controllable over RS-232 serial. If you want a commercial product,
> >you'll want a "TNC" as alluded to by another poster. Kantronics is my
> >personal favorite. Note that you don't need a FCC license to purchase
> >or operate a TNC as such, just to transmit over most radio bands. Be
> >sure you know the rules before you start transmitting.
> >
> >Parallax, of course, distributes its own line of short-range
> >transceivers as well, as do a couple other vendors.
> >
> >If you want to "Do It Yourself", you'll need a modem chip. This is a
> >device which converts serial data to/from audio tones. For 1200 baud,
> >a straightforward Bell modem emulator is preferred. Higher baudrates
> >require more exotic encoding schemes. 9600 baud over VHF and higher
> >frequencies is being done, but is not yet common. (Rule of thumb: the
> >higher the frequency, the higher the theoretical baudrate limit.)
> >
> >MX-COM produces a Bell modem chip called the MX-614 which is
> >suitable. You should check out the PIC-Encoder project of TAPR, a
> >group for amateur data radio enthusiasts. PIC-E is their attempt to
> >create a low-cost, customizable TNC built around a PIC.
> >http://www.tapr.org If nothing else, you can purchase the 614 chip
> >direct from them; it is rather difficult to find in small quantities
> >elsewhere.
> >
> >--- Kevin
> >
> >
> >
> >
> >
> >
>
> Ken Arck
> http://www.ah6le.net
> Amateur Radio Station AH6LE
> [url=palace://stables.xsia.com:9998]palace://stables.xsia.com:9998[/url]
> aka Ph's horse
modules ($6.50 each), that work quite well with simple serial data.
The TWS-434 transmitter with the RWS-434 receiver are real simple to
use, and work quite well with the Stamps SEROUT/SERIN commands.
The TWS-434 transmitter will accept direct serial data from the Stamp
up to 2400 baud on its data-input pin.
The RWS-434 receiver can also be connected to a Stamp on the receiving
end to complete the system. We have schematics, and data on these RF modules
at: http://www.rentron.com/rf_remote_control.htm
Here's a robot project that uses these modules to create a wireless joystick
used to control a small hobby robot as well at:
http://www.rentron.com/ruf-bot.htm
Regards,
Bruce
webmaster@r...
Original Message
From: "LarryGaminde" <lgaminde@t...>
To: <basicstamps@egroups.com>
Sent: Thursday, November 30, 2000 7:51 PM
Subject: Re: [noparse][[/noparse]basicstamps] Re: Using a VHF radio to send and receive data
> If you really need 1200 baud don't read any more of this
> I played around using an old baby monitor and transmitter, using dtmf
> and a holtek dtmf receiver I was able to transmit and receive very
> nicely also very slowly and this is most likely against FCC regs also
> ! but if your looking at getting data from one place to another over
> rf slow and cheep this is it.
>
> Ken Arck wrote:
> >
> > I have one comment to add to this..
> >
> > Baudrate directly translates into the width of the transmitted signal.
> > Typically, 9600 baud is the practical limit of VHF and most UHF
> > frequencies, using standard modulation techniques. Actually, FCC
> > regulations prohibit higher datarates than this for this very reason.
> >
> > If you want mega data rates, consider 2 gigs and up.
> >
> > Ken
> >
> > At 12:03 AM 12/1/00 -0000, you wrote:
> > >> Hi, i want some advice, i want to
> > >> send and receive data with an VHF
> > >> conventional radio, 1200bps max,
> > >> using a pair of BS2SX, i think i
> > >> need a UART?, can recomend me one?
> > >
> > >A UART won't do the job by itself. In fact, its not strictly
> > >necessary for this application if you are bit-banging your own serial
> > >data direct from the stamp.
> > >
> > >The real issue with sending over a radio is converting digital
> > >signals to audio tones, just like sending data over a phone line.
> > >There are numerous commercial products for doing this, usually
> > >controllable over RS-232 serial. If you want a commercial product,
> > >you'll want a "TNC" as alluded to by another poster. Kantronics is my
> > >personal favorite. Note that you don't need a FCC license to purchase
> > >or operate a TNC as such, just to transmit over most radio bands. Be
> > >sure you know the rules before you start transmitting.
> > >
> > >Parallax, of course, distributes its own line of short-range
> > >transceivers as well, as do a couple other vendors.
> > >
> > >If you want to "Do It Yourself", you'll need a modem chip. This is a
> > >device which converts serial data to/from audio tones. For 1200 baud,
> > >a straightforward Bell modem emulator is preferred. Higher baudrates
> > >require more exotic encoding schemes. 9600 baud over VHF and higher
> > >frequencies is being done, but is not yet common. (Rule of thumb: the
> > >higher the frequency, the higher the theoretical baudrate limit.)
> > >
> > >MX-COM produces a Bell modem chip called the MX-614 which is
> > >suitable. You should check out the PIC-Encoder project of TAPR, a
> > >group for amateur data radio enthusiasts. PIC-E is their attempt to
> > >create a low-cost, customizable TNC built around a PIC.
> > >http://www.tapr.org If nothing else, you can purchase the 614 chip
> > >direct from them; it is rather difficult to find in small quantities
> > >elsewhere.
> > >
> > >--- Kevin
> > >
> > >
> > >
> > >
> > >
> > >
> >
> > Ken Arck
> > http://www.ah6le.net
> > Amateur Radio Station AH6LE
> > [url=palace://stables.xsia.com:9998]palace://stables.xsia.com:9998[/url]
> > aka Ph's horse
>
>
>
>