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Re: EFC-7 mod wiring diagram

Hi Doug!

Yes, you'll want to drill two holes, in the EFC-7.  And that's a PHONE jack
rather than a PHONO jack.  Here's my attempt at detailed directions (from

1) Get all your parts before you begin work.  A SPDT switch is the minimum
configuration required.  A DPDT switch will be fine.  If you want to use 
modified EFC-7 as a footswitch, I highly recommend the switch listed below.
    recommended parts:
        1) one push-on/push-off switch, try GC Electronics:
            part no: 35-0490-0000.  This switch has an indicator that
requires no power.  It is a little
            pricey but worth it, IMHO.  The switch is also available from
other distributors.
        2) one high quality 1/4" phone jack, chassis mount.  I've had
trouble with Radio Shack jacks.  I'd
            recommend a Switchcraft manufactured jack.
        3) insulated hook-up wire, 26 or 24 gauge, tinned
        4) optional washers or spacer for switch (see directions)

        1) drill, drill bits, center punch.
        2) soldering iron, rosin-core solder
        3) wire cutters, needle-nose pliers
        4) ohmmeter, VOM, or continuity checker (optional)

2) Make sure your switch will fit in the EFC-7 case.  I mounted my switch 
the upper right corner.  The recommended switch is quite deep.  I.e., it
requires a lot of clearance behind the panel.  Disassemble the
EFC-7 case and try different switch locations.  Make sure the switch will
fit when the EFC-7 is reassembled.

The EFC-7 panel is rather thin so you may need to add a thick washer or
spacer between the switch and the
front panel.  With the spacer/washer in place, the switch protrudes further
outside the case, giving the switch
more clearance inside, behind the panel.  I found my spacer (a white 
cylinder) in the screen door repair parts
of my local hardware store.  I had to enlarge the hole but after that, it
worked fine.  Depending on what you find,
you may also need to shorten you spacer.

When you have a good location for the switch, mark it.  Center punch the

3) Likewise, find a good location for the 1/4" phone jack.  Mark it and
center punch the location.

4) Start with small drill bits, say 1/8" inch diameter and drill the switch
and jack holes.  Gradually increase the hole
sizes until the switch and jack fit.

5) Make sure you remove all the drill tailings and debur the holes.

6) Mount the switch and jack.  Using your eyeballs (less recommended) or an
ohmmeter (more recommended),
find the correct contacts on the switch.  Call them "common", "A", and "B".
Before tightening the switch, rotate
it so that the correct contacts can be easily accessed.

7) Connect the RING of the new jack to the RING of the existing jack.

8) Disconnect the wire going to the TIP of the existing jack.  Connect it 
the "common" terminal on the switch.
Don't overcook the switch when you solder the wire as you can melt the
switch.  If possible, use the needle-nose
pliers as a heat sink for the switch by using it to hold the terminal
between the switch and the soldering point.

8) Connect the "A" switch terminal to the TIP of the existing jack.

9) Connect the "B" switch terminal to the TIP of the new jack.

10) Reassemble the EFC-7.  Loop like crazy!

Hope this helps (and is not insanely detailed)!  Let me know if you've any

Dennis Leas