LFO LED Indicator Wiring Question - Solved

[ddog]

I tried pin 7 - A1  and anode - A2; the LED is always on and not pulsating. The actual LFO is also not working (although I can control it's brightness with depth)

Then I tried the
LED cathode to A1, connect A2 to R6/R7.

and it almost worked!! THe reverse happened:

when the effect is on, the LFO is off (no sound just noise)
and when the effect is off the LFO is on and pulsating (even though my signal is bypassed)


I tried switching the A1/A2 in that case and it all stopped working

So Close!!

for the r6/r7 option I just connected it to one - the r7

[muddyfox]

This makes no sense to me 

Putting an a1/a2 switch before or after the D1 is completely the same thing. I don't get how you got different results.

When the effect is off, a2 is connected to a3 and they are both grounded. a1 and a2 aren't connected so I don't see how you can get current flow through the LED?

Yes, r6 and r7 are connected , as long as you are at the potential where the two are connected together, it doesn't matter which one you connect to.

[ddog]

I re-tried it. This time with
A1 - Cathode

A2 - R6

When I turn on the effect, the LED Indicator is On, but the LFO LED is not pulsating (depth still works, speed does not affect rate)

Turn off the effect, both LEDs are fine

I haven't done a sound test, but I assume since the LFO is not pulsating it won't work.

I'm going to re-try on a clear head tomorrow. Its probably something simple I'm missing.

Here's a stupid question - the anode is negative and usually round pad and the cathode is positive and usually square pad,?

By the way really appreciate the help!

[Stomptown]

Actually Cathode = negative and anode = positive. As far as square/round pads go, I wouldn't count on that as an indicator since some folks use square pad for anode and some for cathode. Just follow the silk screen and place the short led leg in the side pictured as flat.

Has anyone confirmed that the 1776 3PDT PCB follows the same form as the madbean wiring diagram? I ask because there are different ways to wire a 3pdt to achieve true bypass. Some use B1 for their led indicator while most of us here do use A1. Also, madbean connects A2 to A3, which means that A1 is sent to ground when your effect is engaged. I'm not sure if 1776 does this as well but this would cause issues for the suggestions you've been given. If A2 is not tied to ground, you should try to accomplish this using the LED pads rather than connecting directly to the parts suggested.

Before taking another crack at this I would contact Josh from 1776 to find out if A1 is meant for the LED, and if so, if A2 is grounded.

[Stomptown]

I just looked at my schematic for my version of the shoot the moon which includes a mod to urn off the rate LED and it is confirmed to work. For the Grind Customs version you would need to desolder and lift the side of R7 connected to ground and run a wire from that side of the resistor to A1. Or you could remove the resistor altogether and solder one side of the resistor directly to A1. Then solder a wire to the other end of the resistor and run it to the R7 PCB pad connected to the rate led.

[jimilee]

I just looked at my schematic for my version of the shoot the moon which includes a mod to urn off the rate LED and it is confirmed to work. For the Grind Customs version you would need to desolder and lift the side of R7 connected to ground and run a wire from that side of the resistor to A1. Or you could remove the resistor altogether and solder one side directly to D1. Then solder a wire to the other end and run it to the R7 PCB pad connected to the rate led.

I was just gonna say this....mind=blown

[Stomptown]

I just looked at my schematic for my version of the shoot the moon which includes a mod to urn off the rate LED and it is confirmed to work. For the Grind Customs version you would need to desolder and lift the side of R7 connected to ground and run a wire from that side of the resistor to A1. Or you could remove the resistor altogether and solder one side directly to D1. Then solder a wire to the other end and run it to the R7 PCB pad connected to the rate led.

I was just gonna say this....mind=blown

I just updated my post since I accidentally refered to A1 as D1. Oops!

[muddyfox]

I have the 1776 board right here and A part is led-only, a2 and a3 grounded, a1 to cathode round pad.
Unless of course there are multiple board revisions. ;-)

sent from my mobile device

[Stomptown]

If A2 is grounded then you cannot use it in either of the ways suggested. The way I suggested will definitely make the rate led blink and turn off in bypass.

[muddyfox]

Agreed. My bad!
Unfortunately it's a ground plane and cannot simply be disconnected from ground.

sent from my mobile device

[muddyfox]

Agreed. My bad!
Unfortunately it's a ground plane and the pads cannot be simply. disconnected from ground.

sent from my mobile device

sent from my mobile device

[ddog]

Small update - I haven't tried the mod yet. I feel like an artist - who tries to add the finishing touch to his painting and ruins the entire thing. I'm going to keep it boxed up for now and if (when) something breaks I'll try out the mod