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Conference hydra::amiga_v1

Title:	AMIGA NOTES
Notice:	Join us in the NEW conference - HYDRA::AMIGA_V2
Moderator:	HYDRA::MOORE

Created:	Sat Apr 26 1986
Last Modified:	Wed Feb 05 1992
Last Successful Update:	Fri Jun 06 1997
Number of topics:	5378
Total number of notes:	38326

3972.0. "Amiga Video Terminal (AVT)" by DICKNS::MACDONALD (VAXELN - Realtime Software Pubs) Mon Jul 30 1990 08:57

    Interested in combining the power of your Amiga with the video action on
    short-wave radio? I picked up the Amiga Video Terminal (AVT) interface
    by AEA with the AVT Master software by Black Belt Systems over at HRO
    in Salem, NH ($299). This combination allows decoding and display (as 
    well as transmission) of various forms of b&w and color slowscan 
    television signals, FAX, and other modes. It has a number of built-n
    features including the ability to computer-enhance damaged pictures.
    They claim that a received picture damaged as much as 50% can be
    automatically reconstructed to the point that you cannot tell the
    difference between it and the original. 
    
    The interface is a small 5"x7"x2" (approx.) box. One side has an RS-232
    connector for connecting to the Amiga's parallel port. Another side has
    5 radio/tape inputs, a PTT output (to a radio), and an Amiga audio
    input (from the left audio output of the Amiga). The third side has a
    couple more audio interface ports.
    
    The software is quite remarkable (since the manual supplied barely
    touches upon all the features), and is reasonably intuitive. Once you
    have the interface connected to the Amiga, and 13.8 VDC applied with
    the supplied AC adapter, all you have to do is connect the box to a
    radio's speaker jack. Tune to 8.078 MHz, select 120 lpm on the menu,
    then select RX on the menu, and voila, the latest weather satellite map
    of hurricane Bertha begins to paint on your screen in high-resolution
    with 16 shades of grey!
    
    Tune to 20.373.8 MHz, select 60 lpm and RX and voila, another high
    resolution picture appears from the wire services, usually accompanied
    by text explaining what it is.
    
    The system also displays full color amateur slow-scan pictures and
    allows exchange of high-res colors files in 12 seconds over the phone
    lines. The unit has a builtin modem with telephone jack.
    
    The AVT also has a complete ARexx interface which makes for interesting
    possibilities, like automatically saving pictures as they are displayed
    unattended.
    
    Black Belt Systems and AEA claim that new modes of video reception can
    be added in the future through revisions of the software. This system
    can even display satellite photos from the 130 MHz band (right off a
    scanner).
    
    I haven't had so much fun with the Amiga since I discovered
    multi-tasking. Oh, speaking of multi-tasking, while the AVT is actually
    receiving an image, it pretty much takes over the Amiga. Although, when
    you exit, everything returns to the way it was before you ran the
    program.
    
    
    -Paul

T.R	Title	User	Personal Name	Date	Lines
3972.1		WELSWS::FINNIS		`Thu Aug 02 1990 18:24`	8
	Hi Paul, That sounds great could you maybe upload a sample picture, maybe a weather scan... By the way do you get to Internet via packet radio ? KA9Q ? - Pete -
3972.2	WEFAX	DICKNS::MACDONALD	VAXELN - Realtime Software Pubs	`Fri Aug 03 1990 15:02`	12
	RE: .1 I uploaded several pictures in .IFF format (AVT.LZH) and some .PS versions of the same pictures to TAPE::USER2:[UPLOAD]. The .IFF files convert to .SIX files with CSIX.EXE for display on VT240's, 340's, and so on. I will upload some GOES weather satellite photos this weekend. Those are really spectacular! If anyone is interested, I will provide the complete 8.078 WEFAX schedule here. -Paul
3972.3	Hmnnn, I wonder...	CSCOAC::KENDRIX_J		`Fri Aug 03 1990 15:13`	11
	Re: .1 What about intercepting pics from the KH-11 sats??? Or possibly, the latest pic from the myopic Hubble telescope?? (really starting to get going now...) Would it be possible to hook the whole kit-n-k-bootle up to a Satalite dish and go for other...ah... things? Interesting concept... JK
3972.4		MSVAX::BARRETT	This is your brain on Unix; any ??	`Fri Aug 03 1990 15:27`	7
	Sounds interesting; but for someone not into this kind of this I have to ask some stupid questions. I assume you supply the radio, right? If so, what would be recommended (or does a programable scanner do the trick)? I have the same questions for internet over radio. Does it require a license? What equipment is needed? etc.
3972.5	Satellite and the Amiga	DICKNS::MACDONALD	VAXELN - Realtime Software Pubs	`Fri Aug 03 1990 16:41`	26
	RE: .3 Sorry, but encryption techniques used by the government would make such intercepts terribly difficult! You can grab photos directly from the GOES and Soviet satellites though. A scanner and reasonable outdoor antenna are all you need for receiving the signals on the 136 MHz band. RE: .4 You do not need a license to receive, only to transmit. As I just mentioned, there are a number of satellites transmitting grey-scale photos from low and high orbit. Many transmit those photos on the 136 MHz band which almost any scanner can receive. There is also activity up in the 1.9 GHz band which requires slightly more sophisticated receiving and antenna systems. There are also a multitude of stations transmitting on the "short-wave" bands like 8.078 MHz and 20.737.8 MHz. Some of these station transmit 24 hours per day and retransmit the GOES satellite photos. It is a lot of fun this time of year to track hurricanes with these satellite photos. For that type of listening, you need something like a Sony 2010 receiver or other stable short-wave radio that can receive USB and LSB. I am not sure what you mean by internet over the radio. I receive usenet stuff over the telephone.
3972.6	More on WEFAX and the Amiga	DICKNS::MACDONALD	VAXELN - Realtime Software Pubs	`Tue Sep 04 1990 10:46`	16
	Yesterday I tuned into 8.078 MHz to catch the fulldisk GOES weather satellite photo at 10 am. Instead of transmitting one GOES photo at 120 lpm (lines per minute), it transmitted several low-orbit MET4 satellite weather photos at 240 lpm. I've also learned since my original posting that the satellite photos are transmitted in 64-level grey scale. The Amiga converts that to a 16-level grey scale. Using the software's tuning "scope" it is possible to redesign the demodulation curve to give a nicely contrasted 16-level grey scale image. If anyone is interested, I have a piece of wefax software along with instructions for building a simple hardware interface ($25 worth of parts at Radio Shack). Then all you'll need is a shortwave receiver with a BFO. I'll upload sometime this week to TAPE. Paul
3972.7	i'm impressed	STAR::SLACK		`Tue Sep 04 1990 18:17`	7
	I was over at Paul's last week and saw some photos coming in from Central America via the AVT and one of Paul's radios (he has about twelve thousand radios and antennas at his place). It was very impressive, both the picture quality and simplicity of operation. If you've got the radio, I would recommend the AVT setup highly. Bill
3972.8	Please Upload	WELSWS::FINNIS		`Tue Sep 04 1990 18:19`	10
	Yes... Please upload How much interefernce suppression equipment do you use ? My Stereo complains about my Amiga and the modem.! By the way have you cross-posted this in the meteorology notes-file - Pete -
3972.9	sure would like the PD stuff!!	CGOFS::OAKLEY	BCNU2	`Wed Oct 03 1990 13:24`	11
	re: .6 Paul, do you have the piece of software and circuit mentioned available yet. BTW: what does BFO on the shortwave receiver mean? wayne
3972.10	BFO = Beat Frequency Oscillator	GOBAMA::WILSONTL	Tony, the HOSS TRUMPET	`Wed Oct 03 1990 15:25`	1

3972.11		DICKNS::MACDONALD	VAXELN - Realtime Software Pubs	`Thu Oct 04 1990 16:28`	5
	BFO = Beat Frequency Oscillator Someone else was looking for it. I may have deleted the UUE file.