Electronics
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Springs connect components and wires. |
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Schematic is on the face of the radio. |
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View from the back. |
For a change from projects built of balsa, foam, or recycled materials, I purchased a radio kit that cost $20 at my
local hobby shop. Electronic components are connected to springs inserted through a cardboard circuit board. No
soldering needed. The kit consists of four resistors, five capacitors including a variable capacitor and one transistor.
There are however additional components on a small circuit board which is the tuner assembly.
The color coding on the resistors and the lettering on the capacitors is really small so I would suggest a
magnifying glass. When pushing the springs into the cardboard circuit board it appeared to me that one end of
the spring would push in more easily than the other. The holes that the springs went into were numbered and
there were graphics indicating where the components went on the top side of the circuit board but the bottom side
where you connected the component leads to the springs was blank. It was pretty easy for me to figure out the
correct spring when looking at the bottom because you just pushed the leads through small holes near the springs
they are connected to.
This radio receives two different shortwave bands 6 MHz to 8 MHz or 12 MHz to 18 MHz switch able by moving one
jumper wire. The radio does not pick up the normal AM band like I had assumed. I found to pick up anything at all; I
needed to connect the antenna wire to something to improve the antenna. Connecting to a ground improved the
signal further. In the instructions it is stated that range can be extended up to a 100 times by doing this.
For me the instructions were adequate but some additional information on antennas and the characteristics of
shortwave radio would be nice, but considering the low price of the kit I would not have expected more. You will
learn more from this project if you do additional research like I did. For instance I learned that shortwave reception
is better at different times of the day and during winter but it helps to experiment with your radio for best times.
Summary: this is a good electronics project, much can be learned from this especially if you do additional research.
The box of the kit states, “learn how a radio works”, the instructions are very brief on how a radio works. Additional
materials needed are only a 9-volt battery. For tools I only needed a needle nose pliers and a small screwdriver.
For many groups building this radio; not having to solder components makes for a cheaper, safer, and more
convenient group project.