This afternoon, I built another YACK keyer with an AtTiny85 chip, this time ignoring the “DigiSpark” cloning, like in my blog post (see above).
I tried to make it as small as I could with what I found in the junk box. Of course, if someone would design a PCB and use SMD components, it could be even smaller.
The biggest part was the battery, I found nothing smaller than this 650 mAh Li-Ion cell from a cordless phone (the black rectangle in the picture).
If it were not for the battery, the whole circuit could be housed in a 7 cm piece of electrical conduit.
Total weight with cable, but excluding a paddle, is only 48 gram.
The circuit has become really simple this way:
73,
Luc ON7DQ