external foot switch for mini looper pedal?

[mitchg101]

I plan to build an external looper foot switch wired into a Lekato mini pedal looper using a 2-wire SPST Momentary Foot Switch (normally closed? not sure yet). I hope to wire it into a larger, more stable flat pedal rather than the existing small, unstable switch jutting out of the mini looper pedal.

Am I on the right track, using a two-contact SPST momentary switch, soldered to two appropriate contacts in the looper's switch? Or must it have as many contacts as the looper's switch, and all be cross-wired? I'd like to activate record, playback, overdub, etc. exactly as the internal switch does, but with a larger, external flat foot switch.

[ElectricDruid]

I don't suppose you've managed to find a schematic?

Failing that, some good photos of the insides of the pedal and the switch would help us help you.

Thanks!

[Ben N]

I've driven one, and I thought the pedals were fine.



I'll show myself out.

[deadastronaut]

i think as the footswitch has 3 tapping modes it is controlled by a micro controller, so not as easy as just adding a switch..or switches.


could be wrong, but doubt its as easy as that....just my 2p.

1 tap record
2nd tap overdub
double tap stop/
hold clear...etc. all on the same switch....  hmmmm.....

[aron]

Have to look at the inside, and see what the switch looks like. It sounds like your standard looper pedal.

[ElectricDruid]

i think as the footswitch has 3 tapping modes it is controlled by a micro controller, so not as easy as just adding a switch..or switches.

could be wrong, but doubt its as easy as that....just my 2p.

1 tap record
2nd tap overdub
double tap stop/
hold clear...etc. all on the same switch....  hmmmm.....

I agree that the switch is connected to the looper's microcontroller, but in my experience that generally makes things easier, not more complicated. Switches on microcontrollers are typically SPST NO momentary with a simple short-to-ground action. This is because many chips have built-in pullups on the IO ports, and you can do "latching" features in firmware, so there's no need for a latching switch. As such, you can generally connect another switch in parallel with an existing one and have a secondary switch that does the same job. I would guess that's the case here too, but we do need to see inside.

[deadastronaut]

ahh gotya....learned something today then. 

i think as the footswitch has 3 tapping modes it is controlled by a micro controller, so not as easy as just adding a switch..or switches.

could be wrong, but doubt its as easy as that....just my 2p.

1 tap record
2nd tap overdub
double tap stop/
hold clear...etc. all on the same switch....  hmmmm.....

I agree that the switch is connected to the looper's microcontroller, but in my experience that generally makes things easier, not more complicated. Switches on microcontrollers are typically SPST NO momentary with a simple short-to-ground action. This is because many chips have built-in pullups on the IO ports, and you can do "latching" features in firmware, so there's no need for a latching switch. As such, you can generally connect another switch in parallel with an existing one and have a secondary switch that does the same job. I would guess that's the case here too, but we do need to see inside.

[mitchg101]

Figured it out.  Thanks to all, and yes, the microcontroller simplified things.  Right under the rear plate (4 screws) of the Lekato Looper Pro there are four contacts where the switch meets the board.  Ohmmeter proved them to be "normally open" and that they were paired (two X, two Y).  Shorting them briefly activated the looper's record & play and shorting for 1/2 sec. activated erase as expected.  Soldering in a "normally open" foot switch will be easy as there's plenty of space for a drilled hole and cable snaked through.  Now I can use an ergonomic, light-action, full-size foot switch instead of that dopey protruding thing with all its extra wasted motion before it makes contact.

[rogs]

I made a simple interface to use an external footswitch with a Lekato looper. See here: https://www.loop.jp137.com
Really intended primarily to allow a 'one tap' stop, but the '2 switch' version allows all functions to be controlled by 2  'normally closed' footswitches
A simple project - CMOS logic - stripboard layout, no coding.
And Just a single wire soldered connection to the pedal PCB required....

[mitchg101]

Wow, so I'm not the only one wanting to go in and fix the darn thing.  How great, especially the two switch version!  Your skills/knowledge are way beyond mine, but can I ask how you soldered the lead to the board?  At no matter what temperature, it fell off with soldering paste & good silver solder, till heat ruined the board itself.  Am starting over with a new Lekato and instead of soldering, I will use silver wire glue/adhesive and a piece of flexible sponge to hold it in place when case is closed.  This thing is very sensitive to heat!

[rogs]

I haven't had any problems soldering to the Lekato PCB?...
Mind you, I have no experience working with this 'silver solder' you mention (I'm so 'old school' I still think silver solder is for working with jewellery!    )
I still use good old fashioned 0.7mm multicore 60/40 tin/lead solder, working at around 325 degrees C ... I've had no problems soldering to the ungrounded switch terminal on the PCB.

Couple of points --
• You'll already know that you need a 'normally open' footswitch for the mod you're trying, and not a 'normally closed'.
• You need to be a bit careful - especially if you live a in a 'dry' climate area....
Taking the Lekato switch to the 'outside world' as it were, it would be best observe CMOS protection techniques when you plug the footswitch in....
Temporarily ground yourself by touching the case of the device (which is also common to one side of the switch BTW)) immediately before you plug in, to prevent any static build up from destroying the pedal.

[mitchg101]

You should've been a doctor, Rog.  Wow, you were right, heat didn't damage it, as proven by later solderings.  It had to be static.  So, my second attempt was much better.  Also, I switched to a flat-end solder tip:  much better heat distribution, and yeah, my solder's not silver, duh.  By the way, a rechargeable 9v li-ion in the attached case runs the Lekato for hours.  And I've reengineered the internals of the footswitch for clickless, no wasted motion so my loops now synch with greater precision.