Steve, GW7AAV's blog post Computational Nostalgia brought back memories of some of the ham radio related things I used to do with the early personal computers. I actually passed my Morse test in 1979 after practising with a morse tutor I wrote in Z80 machine code on a home-built Nascom 1 with 1Kb (yes, that's right, 1024 bytes) of RAM. I've written numerous Morse training programs since then including MorseGen and Morse Machine and I still struggle to go faster than 12wpm!
I wrote a Morse decoder for the Sinclair Spectrum that very occasionally printed out a few correct words from an interference-free S9 signal. And I sort of invented PC sound card software, although the memory of it now causes me some embarrassment.
I had an ERA MicroReader which decoded RTTY and displayed it on a digital readout. I wanted to try contacting the stations I heard, so I wrote a program to generate RTTY "diddles" by sending BEEP commands to the sound card. Except it wasn't a sound card - I don't think they'd been invented in 1986 - it was the PC beeper, an altogether cruder device. I can still remember working an Italian station by holding the mic close to the PC speaker while my program diddled away until it was pointed out to me that the far from sinusoidal audio waveform was causing my signal to appear in several places!
Well, ham radio is supposed to be about self training, and I learned something from that...
It brings back memories indeed. Still remember the Sinclair ZX80and the Sinclair ZX Spectrum with the so called dead flesh keyboard. Waiting for half an hour to load Microsoft Fligtsimulator 1.0. What a sensation. Later there was the Sinclair QL I believe a sensational design with microdrives. The computerworld changed a lot over the years. My first "radio" computer was an old 8086XT with one floppy drive of 360kb and no HDD. Monitor was orange monochrome I used it for packetradio with an old version of SP.
ReplyDeleteThanks for the plug - I loved my C64s and with a friend we made a few extra quid fixing them. I knew every fault that could occur and which chip it was. It all started when we paid £5 for a large box of over 100 faulty circuit boards at a radio rally. I too wrote a few programs to do various radio related calculations and I ended up combining them in to a program called "Ham Calcs" which I included on a disk full of radio related programs. It was just a menu driven collection of just about every calculation you might ever need. I gave it away to anyone who wanted a copy. Two or three years later I was gob smacked to find it on a magazine cover disk. I wish I had kept up the learning process and learned more programming skills.
ReplyDeleteAll this talk brings back memories :-) I coded a CW decoder on a VIC 20. I didn't have much money as I was in high school, but I built a simple interface with rectified audio driving a transistor driving a relay to the VIC 20 joystick port. It worked OK when you had an S9 signal. I wrote some assembly executed by an interrupt to read the joystick port and somehow the BASIC program interfaced with the assembly code; it was my first foray into "multitasking". I'm amazed I was able to do so much with only 2K of RAM. I wish I still had that code.
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