1202 ALARM

National Commando 505 circa 1975, £30 on eBay. When I was growing up in Bangor there was one of these for sale in the window of Dennis Brown's electrical shop. It cost a fortune, but looked incredibly cool with the military styling and top handle. I've been tracking these on eBay for over 5 years until I could get a good one at a reasonable price. Analogue TV signal provided by the modulator from a broken Acorn Amiga RF adaptor. Runs at 12 volts on UHF channel 3. Remember when you had to tune your TV into the VCR, then Channel 5 came along and messed it up? Same idea.

Finally got round to sorting out a large number of ICs. TTL, CMOS, I2C, PIC and ATMega microcontrollers, monolithic amplifiers and a huge bunch of assorted 555 timers. Dumped a lot of obsolete ones too to make room. I found a LM1881 video sync separator I was looking for a few months ago. Coupled to a HEF4066 analogue switch a composite video signal can be manipulated. 25 years ago I built a simple video fader for film editing based round these 2 integrated circuits, but now with microcontrollers a lot more TV experiments are possible. 

So I purchased a flip-digit clock in eBay and after 3 weeks in transit from China, it arrived like this.  I asked for (and received) a full refund and as the seller didn't want a broken clock returned, I chucked it in the spares box. A few weeks later I had an hour so took the clock apart and discovered a rogue piece of plastic sprue had jammed the mechanism. Putting the 20 or so loose numbers back in place was a bit fiddly, but now it's working fine and keeps excellent time. There's also a loud and satisfying click on the hour.