04 April 2011

Modding PLL MC145106

Original configuration
 Back to my Pearce Simpson device, I have decided to go through all the steps necessary to make it "digitally" tuneable.

In order to set free the 2x4008 I had to unscrew the front panel and remove all knobs. The black plastic can be removed and the front panel structure detached.

Chips are now exposed. This is "old" technology, so with a solder wick and a thin tip I could set 4008 free just with 3 lifted pads.

2x 4008 on their new sockets
It took a bit of work to get the new sockets in, and they are not perfectly aligned to the board, but the melt solder did the rest and joined everything (checked).

As a final check I plugged in the replacement ICs, connected a dummy load and a frequency counter and made sure that it tunes around.

Next is to draw a board that holds an ATtiny2313 for tuning up and down, AND to make sure that it all fits inside the case before melting any other solder! Oh, yes, I have one more cut trace to restore.