Slow Scan TeleVision
- Slow Scan Television Explained (pdf)
- Proposal for SSTV Mode Specifications, A.K.A dayton paper pdf
"Unlicensed operation on the AM and FM radio broadcast bands is permitted for some extremely low powered devices covered under Part 15 of the FCC's rules. On FM frequencies, these devices are limited to an effective service range of approximately 200 feet (61 meters). See 47 CFR (Code of Federal Regulations) Section 15.239, and the July 24, 1991 Public Notice (still in effect)." Part 15 Devices by ffc
picture via next.gt
expert from A Micro Radio Manifesto, read the manifesto!
LPFM covers up to 100 watts. "Community FM" in Japan (which was legally introduced as an institutionalized "Mini FM") allows 10 watts now (initially up to 1 watt). I think even these power levels are too much for micro radio. What about one watt? What about below one watt? Such a micro-power radio station could cover only a street block radius or only a housing complex. Why not? Leon Theremin showed the minimum example of micro radio. His invention is not only a musical instrument but also a micro radio.
- AM using a crystal
- 300m FM transmitter ytube
- grandady of all "spy" circuits >> dig here
- modules 1 from this blog
rtl-sdr spectrum analyzer
the information is send using FM and needs only 800hz bandwidth for data (1500hz-2300hz) and 200hz for control (1100hz-1300hz).
Robot 36 transfers 320x240 color images in around 36 seconds, hence the name Robot 36.
Since the Pi can generate the HF FM signal itself, no additional electronics are needed for low power transmissions.
- pySSTV - Python classes for generating Slow-scan Television transmissions github
- Slowrx - A decoder for Slow-Scanning Television (SSTV) github linux
Flying sPot Scanner <3
Uploaded on May 15, 2009 Television in a 10 kHz bandwidth, 32 lines, 12.5 pics/second. This was the first recording I made via my "live" electronic flying spot scanner on 4th November 1973 - I was 19 years old at the time. I was scanned by the light of a P11 phosphor CRT (type 5LP11), focussed onto my face through 4 1/2 inch diameter magnifying lenses. A 931A photomultipler picked up the light reflected by my face and fed the resultant video signal to one channel of a stereo open reel audio recorder. The other channel of the stereo pair recorded my voice. I was a bit lost for words after an all-day construction effort, culminating in this video recording being made at 1 am. The recording was made at my parents' home, 6 Torring Road, East Hawthorn (Melbourne) Victoria, Australia. I was in my first year of Electrical Engineering at Swinburne Tech College at the time, hence the reference to exams.
The original "audio" tape was converted to a Youtube-compatible .mp2 file via software kindly provided by Gary Millard, refer: http://users.tpg.com.au/users/gmillar...
All of my earlier "video" recordings on audio tape had employed mechanical scanning, with a Nipkow scanning disc. This electronic scanner was developed in association with the late Daniel Van Elkan, then VK3UI (b.1952 - d.1986), who designed the 32:1 divider chain for the scanner.