Replacing footswitch during a rehouse

Started by swinginguitar, June 15, 2010, 09:23:18 AM

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swinginguitar

I'm modding/rehousing a Dan Echo. I removed the old switch (6 lug spring loaded momentary type). Let's say the contact points on the PC board are:

1 2 3
4 5 6

connecting any combination of 1-4, 2-5, 1-5, or 2-4 turns the circuit on and off (the status LED comes on anyway). 3 and 6 seem to be isolated on the board and not connected to anything.

Question 1: how can I get the circuit to be "always on" rather than be toggled?

Question 2: I'm trying to true bypass it - I have the hard bypass working, but i'm not getting input/output to/from the pedal when not bypassed. I ran the appropriate wires from my 3pdt switch to the existing input/output on the PC board.....but no signal when not bypassed. perhaps i could bypass the original switching altogether?

Any insight would be a big help.....

stringsthings

which wires are connected to the input jack and the output jack?

swinginguitar

I'm using the switch layout here: http://gaussmarkov.net/wordpress/thoughts/wiring-up-a-1590b/

bypass mode:
input jack -> switch
switch -> output jack

not bypass mode:
switch connects to input terminal on PCB
output terminal on PCB connects to switch

make sense?

as for the old momentary switch, I just removed it and soldered in wires to each terminal in an effort to figure it out...not sure what to do next.

I'm guessing this is a "flop flop" type circuit? Wish I had a schematic to see how the signal flows through the switching area  :icon_sad:

stringsthings

it would indeed be a good idea to acquire the schematic .... do you need help finding this?

swinginguitar

haven't been able to find the schematic.

updates:

- the true bypass/input/output issue is clear - wiring problem. so that leaves only the issue of getting the circuit to be always on at power up

- this unit indeed uses a flip flop - HCF4013BE chip. i'm in over my head on that...no idea how to bypass it or trick it into always being on....i'm not following the circuit at all....

swinginguitar

SUCCESS!!!

By jumping 2 pins on the flip flop chip, the circuit stays engaged full time...

So I now have a Dan Echo circuit with true bypass , an op amp input buffer that impedance matches much higher than the stock transistor, infinite feedback (oscillates), and footswitchable short/long delay time (with status LEDs indicating which is active).

Time to lay it all out for a (big) enclosure and wire up LEDs!!!

Ronsonic

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