Tag Archives: Echo-Matic; echomatic

PCB’s for the Tape Delay project

4 Nov

Since the last circuit failed, Ive made some “proper” boards:

Last time I used this method was about 15years ago… If you photocopy (lazer) the circuit in reverse to some glossy paper, you can use a high temp iron to transfer the pattern to copper laminate board, once its on, soak it in some water and remove the paper

Unfortunately I only have a mini travel iron that wouldn’t output enough heat, so many of the tracks were weak.

Fixed up the traces that didn’t stick, with a sharpie:

Kitchen sink is always a good place for dangerous acids:

After the acid bath:

Clean the toner off and you’re left with some (slightly patchy) copper traces:

Not the greatest soldering, but its on there.


Tape Delay Project

3 Nov

Since I’m in LA and my Truck is sleeping in Georgia, I needed something to keep me busy.

I bought 3 old Marantz PMD-222 pro Tape decks, that were sold as not working/junk.

The plan is to build a analog tape delay effect. Ive got the tape decks working (so I have 2 spare now) and I figured out how to control the tape speed in both play and record modes. Ive also built a mixer circuit on some vero board


But… It didn’t work.

Im not really sure what was going on, I’m got an audio signal to the tape but no mixed signal output, Im guessing there is a mistake in my circuit. Do I cut the red wire? or blue?

I’ve given up with this approach and have etched some pcbs on copper boards… stay tuned.