2016-08-07

Amateur Radio in the 21st Century [1]


As I write this, we are still without power after an hour. What made me write this? Well I thought of this subject this morning. All day it has been at the back of my mind. Something for the younger and newcomers to the hobby of “Amateur Radio”.

In the old days, that is before 2000, we amateurs “hacked” our hardware. Whenever someone threw away some thing that we could use, we 'acquired' it. Adapting wartime radios, assembling kits or developing new hardware, we 'hacked' it.

Last century as a constructor you could drive into Johannesburg and visit a component store. Here on the West Rand, you could drive to the top of CR Swart and visit “Vidi-Kits”. These stores have mostly disappeared or service our small electronics companies. Our market here in SA is minute in comparison to a major city in Europe or USA. It is not big enough to support the small number of constructors or electronic enthusiasts. All the components are imported. Attracting import duty. With the exchange rate not in our favour, the value of a component is way beyond a youngster with pocket money or a pensioner.

Some time ago, I suggested to some members that the only way 'we' will acquire components in future, will be by taking electronic hardware apart. After all some Africans are already gaining notoriety on Youtube constructing wood-burning-cutting laser devices using DVD writers! Whilst others [Germans] are tutoring hackers in CNC machines using parts scrounged from CD/DVD drives and mice [the computer kind!].


Component Mining

A lot of hardware survives a catastrophic failure or electrical surge. Ironically the fuse in the ATX power supply used in most modern desktop PC's, never blows! Most of the transistors are re-usable in virtually any application. They were supposed/reckoned to last 150 years in the 1960's. Most will lie unused in a landfill. Certain IC's will also provide a long and useful life, if you can determine the function of the IC from the obscure number. Fortunately for you these days we have very good search engines on the Internet. A small IC inside a CD-ROM drive turned out to be a 300 milliWatt stereo audio amplifier.

A lot of the cases or housings can be re-used. The metal [thin!] box the ATX power supply uses can house a variety of constructed projects. The power supply used in old [out of date] networking product can power a lot of TTL and CMOS circuitry. Usually these are non-switch-mode power supplies. Therefore they are 'RF clean'.

Old television sets, radios and computers, can provide suitable parts for use in a multitude of projects. Sometimes the construction or assembly can be obstinate in getting at the parts. Expertise is quickly gained after a few mishaps. At the very least this will improve your soldering! De-soldering joints is not an art but a skill. After the first dozen components it becomes second nature to apply sufficient heat and some new solder, to release that 1% resistor from the PCB.

More to come ...


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