CONVERTING EQUIPMENT
FOR USE ON 500KC

A Portable Radio Model is
Coby CX53, cost $4.95 at Big Lots.



The display is for a built-in clock and also frequency/band display AM/FM.

Specs on the back!




We will be using the AM radio function.
PDF of the frequency counter chip in the unit.
PDF of the receiver AM/FM chip in the unit.

Range of the frequency counter (built-in) is DC to 150 Mhz.



Unit has audio output jack and runs off two (2) AAA batteries, and has a whip-type antenna!

With a few cap additions we can lower, the lower frequency limit.
Set now to 400 KC!



Also we can set the upper end of the portion of the band we want.



Which gives ample coverage of the 500KC portion of the band
for the ARRL experiment. around 505 KC tune-able.




Tuning is rather fast but I am attempting to slow it down so we can
center up the Experiment frequencies.

Here is the schematic of the tuner device and "radio" circuit.
The PDF of the Spec-Sheet is >Here<.