My son provoked me to lead a radio club in elementary school. Those of you who have tried to do something similar know what the current conditions are for ring activity. Nevertheless, I managed to get the ring going. We started in primitive conditions. The local school currently does not have workshops for technical education (the hygienist closed them due to high humidity). So, thanks to the understanding of the school principal, we were able to start in one class. 13 children came to the first meeting, pupils of the 6th and 7th grades, plus my daughter - a fourth-grader. Here we definitively agreed that we will meet every week on Wednesday at 17.00.
For the second meeting, the children should have brought "breaking terminal blocks". 15 of them have already arrived. In order not to discourage them and especially the parents in the current economic situation, we started by building a crystal with a single-transistor amplifier. I scavenged most of the parts from my "veteshnik" stash. GC520 germanium transistors and 50 ohm telephone headphones. The children wound the coils, with varying degrees of success, on the paper tubes on which the microtene bags in the food were originally placed. The biggest problem was the rotary condenser. Where should I have gotten 15 at least approximately the same swivels. I remembered the old designs and tried a sliding capacitor from a matchbox. I was pleasantly surprised to find that it has a maximum capacitance of about 140pF and a minimum of around 40pF. Absolutely perfect parameters for such a primitive product. And mainly from available material. What did we use? One matchbox, a piece of aluminum foil, two about 10 cm pieces of wire from a telephone cable, and a wide transparent Chemafol adhesive tape as a dielectric. The success was huge. The children don't want to leave at half past seven and are curious about what we are going to do next.
Now I keep them busy with theory, but only within the limits of their understanding and knowledge, especially mathematical. Of course, we will not only focus on the construction of equipment, the component base would not be enough for that. I will show them amateur radio connections and they will also learn the basics of serious CB operation. I could already hear some voices: "Are you going to teach them at CB?!" Yes on CB, but so that they do not have to be ashamed of the way of operation even in front of experienced OMs. After all, CB is more accessible than classic amateur operation. After all, for the price of one M160 today, you can get a simple CB station. Children have to wait at least 3 years (up to the age of 15) to operate in amateur bands, and they will be able to start now on CB. I'm thinking that if we can get enough CB stations, we could start a local network operation and maybe sea training via CB. So that we don't just stay in operation, I plan to gradually build an amplifier with LM386, a feedback audio unit and possibly a direct mixing RX on 80 m with them.
By the way, does anyone have unnecessary rotary capacitors with a capacity of around 100 pF? Our "boxes" are not suitable for short waves. I am attaching two pictures of the ring. On the first is the children's part and on the second is our crystal with box tuning.
Miro OM3CKU
om3cku@centrum.sk