Hi all,
The Lectron system was always very famous for the radio circuits.
Unfortunately, many AM stations disappeared.
Luckily, new stations arrived, but these are located far away and the original Lectron radio circuits aren’t just sensitive enough to pick these up.
Time for a change !
In the spirit of Guenther Stabe, let’s build a very sensitive and selective AM radio !
For this, we need to create a new AM tuner module.
This is fairly easy as most pocket radios have already the parts inside and we can salvage these.
I also made use of the newly 3D printed white lids to construct the module.
For the transparent base, I used the one of a battery module.
These are some close-ups of the AM tuner module :


All other modules are the normal Lectron modules.
The magic happens in the AM module, which comprises a MK484 radio chip.
It has a very high impedance input, several HF amplifier stages and a dedector stage.
With P1,we can set the sensitivity of the radio. P2 is the volume control.
This is how it sounds : AM audio recording
Here’s the diagram :

And here a setup picture :
