Digital data transmission over VHF

[123abc]

Hi.
I'm new and not yet a licensed ham radio user. I got interested in radios from when I started building circuits from kits. One of my favourites I made was an FM transmitter.
Anyway I have been using this FM transmitter along with a receiver to send and receive stuff like RTTY and SSTV between two computers.

My latest experiment was a little more ambitious. First encoding any file type into text format using Base64 then using the software fldigi on BPSK-500 mode to transmit the text to another computer where I decode the text back into a file. As you can imagine it is very slow, transmitting/receiving no more than 40 bytes per second.
I have tried out EasyPal and DIGTRX but they are no better (I think).
I know that BPSK-500 is lower bandwidth and designed for operating on lower frequencies than the standard FM band. Is there any mode that can send telemetry faster?
fldigi does have something along with it called flarq but I'm guessing you need two way communication which I don't have yet.
I have also read stuff about 1200 baud and 9600 baud transmissions from sound cards but I can't figure out how and what I'm supposed to do.

[5B4AJB]

Try Digtrx (my personal favourite, also the highest data rate) again using the best channel options, you can get over 6kBit throughput.
The volume settings are extremely sensitive to set up, but it works very fast when set up right.
You'd be looking at about 1MB/hour on full speed.

Packet radio (1200 & 9600 Baud) are an ARQ mode, that is, they need a transceiver at both ends.
To do packet with a soundcard, I reccomend AGW Packet Engine & Winpack.
This system takes more setting up, but again, once it's done, it's done.

For recalling the soundcard settings (once you have set them up to the right levels), I recommend a program called Quickmix.

BTW, what you are doing is real ham radio - go apply for a license and get a few books, you should pass easily...

[m0bov]

Get yourself a ticket and then use your data skills to talk to other stations in other countries! Maybe join BARTG as their data mad.

[John_D]

I think the easiest would be http://www.airlinkexpress.org/http://www.airlinkexpress.org/ which offers various data programs. have a listen first. By far the best way is to run data through an external soundcard set-up such as Signalink. And you don't need massive power to work long distances. There are many modes which you can use on VHF. In many cases your rig can work stations which you, the operator cannot even hear. JT65 for example can hear signals up to -30db, thats MINs 30dbs under noise.
Have a look at how easy it is to hear data qsos here. Check out K7AGEs videos:-
http://www.youtube.com/results?searc...age+psk31&aq=2

[123abc]

Thanks for your replies. I am considering studying for the license soon. I have also been interested in receiving weather NOAA satellite signals. I have managed to pick up some signals and just about figure out what they are showing using WXtoImg. I used an airband scanner from a pilots' shop and its original little antenna. Is it illegal for me to do this without a license? I want to make a larger antenna to get better reception. I will only do it if it is legal right now otherwise I will wait till I get my license.

[John_D]

This answer only affects you if you are in the UK

Is it illegal for me to do this without a license?

No its not illegal.. The only bit which makes it illegal is the peculiar statement that any messages outside the frequencies which you are licenced to listen, can only be relayed to the Secretary of State! so technically you cannot discuss the contents with anyone else. So do you think anyone acts on this???? :-)