PA2ION (picture 2013 :)

Living with 'Radiation' at work and hobby

As 'active worker'' over 40 years varying techniques of spectroscopy were used over a wide range of the electromagnetic spectrum: infrared- visible light- UV- Röntgen/gamma radiation and alpha- & beta particles used at analysis and experiments: each group has its own physical characteristics.

In 1976 the novice license for radio amateur was received, few months later the full license. Many radio contacts (QSO's) were made all over the world.

The radio hobby has many technical possibilities for experiments.
Articles of the decoding of very weak CW signals started many trials with home made logical circuits but results stayed poor and computers finally were introduced for learning and many experiments.
The new CBM64 was very popular by its clear documentation and became fine working digital solutions for several radio communication modes as RTTY, facsimile, packet radio(VHF/HF!).
There was an option for a low resolution camera with digital pictures in 8/16 gray shades(!).
At a home experiment the CBM64 was combined with a DOS/IBM computer and usage of of home made assembler programs. The tandem enabled many SSTV QSO's (in low resolution) on VHF and HF bands. Making own, working, software solutions on this way gave a lot of fun.
There was a very short period for undisturbed (!) packet radio QSO's using home made modems on the 20 meter band: my first CQ broadcast signal caused three connections requests from three different continents while using a simple inverted 'V' antenna and low power. Try this again action nowadays!

Mapping of geographic data might give fun: for a decade ago about 10 percent of the Dutch radio amateurs was logged as APRS user. APRS shortly: mobile radio amateurs send by broadcast GPS coordinates and small message data with Packet Radio.The broadcast info is decoded and subsequently is transferred into map views. Motions of objects become visible as tracks.
The combination of the programs MixW (info internet, for log file) + VBAPRS2MAP (=decoder, organizer) + VBAmap (mappings) can do this job automatically. Details for those are described elsewhere on the website.

Year 2018
Software Defined Radio' (SDR) surely will be a new hype. First receiver tests with a small, cheap RTL USB stick and a home made 100 MHz up converter and downloaded software for analog and digital radio with a panorama overview for signals over a bandwidth up to (max.) 3 MHz were very promising (DC - 1.7GHz) for both analog and digital radio.
We are watching the developments.

Examples of products using home made software

Decoding and conversion of multiple (mobile) stations, location & short message data and their subsequently mappings & data listings:

Example 2007: Vessel track: Packet Radio audio->MixW log->VBAPRS2MAP->Vectors&Tables->VBAMAP->map(s) [screen dump].

Period 1985 - 1995: example home made SSTV:

Home computer CBM64 and DOS XT computer both necessary to make a SSTV station
 
  

Left: IMAGE with a CBM64. Pictures were made by a video module supplied to the CBM 64 (max. 8 colors !) and then, after transport of the data to the PC with a parallel cable, the system ready for QSO's on HF/VHF.
Right: the very first SSTV picture was captured on 14MHz with a CBM64 and the famous COMin64 program.
(readability is enhanced when viewing at larger distance).

Left: text transmission: primitive 'peek and poke' methods were applied to bring large character images data into a memory part that reserved for the  SSTV image.
Right: hardware SSTV receiver for fast modes of SSTV. It enhanced the quality of received pictures by its enhanced number of gray shades.

Enjoy,

73 - Ron