Adding LED indicators to switched mods

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stinki
 
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Adding LED indicators to switched mods

Post by stinki »

OK my brain is a little fried from all the soldering and crafting I've been doing on the xox.

I'm now pretty much done, added all the mods I wanted, everything working nicely...I'd like to add a finishing touch of little LED's that illuminate when the switches/mods are activated, but I'm really a beginner when it comes to understanding circuits..I'm using DPDT pushbutton switches for all the switchable mods -- bass boost, res boost, env range x3, etc. So all the switches have an extra row of pins (except for the bass boost button, which uses both rows). I'm a little lost after that. Where would I get juice/ground from? I assume I just need proper voltage going to the free center pin, and to a side pine a 4.7k (or whatever) resistor connected to the LED anode and then connect a convenient ground to cathode...Any tips or examples for brain-fried novices?

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altitude
 
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Re: Adding LED indicators to switched mods

Post by altitude »

DPDT switch with a 5V rail,resistor, and LED in parallel with the on-off of the mod is the simplest

stinki
 
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Re: Adding LED indicators to switched mods

Post by stinki »

I'm still a beginner. I understand the basic concept at play in making the switch but technically I am still confused. Can you give me an example?

For instance here's the bass boost mod wiring that uses a DPDT switch to select an alternate set of caps for C20 and C21

switch pin1a - .1uF
switch pin1b - .1uF
switch pin2a - .01uF
switch pin2b - .01uF
switch pin3a - C21 (pin1)
switch pin3b - C20 (pin1)
.1uF - C21 (pin2)
.01uF - C21 (pin2)
.1uF - C20 (pin2)
.01uF - C20 (pin2)

Where would an LED fit into this? Could it, since both rows of pins are used on the switch?

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altitude
 
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Re: Adding LED indicators to switched mods

Post by altitude »

For that, use a 3 position switch

stinki
 
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Re: Adding LED indicators to switched mods

Post by stinki »

OK, so I was understanding that correctly then, at least..

How about a simpler example then, the Env range x3 mod for instance:

- center post of spdt switch to 100k, then to one side of R63
- "on" post of spdt switch to the other side of R63

I've got it on a DPDT switch so I've got that extra row. But I really am so new to this I can't figure out how to connect the LED. Where should I draw 5v from? I don't want to draw it from anywhere inappropriate...A specific example would help enormously, but thanks for any tips and your patience

stinki
 
Posts: 7
Joined: Mon Mar 01, 2010 10:53 pm

Re: Adding LED indicators to switched mods

Post by stinki »

For instance, what about drawing the 5v from pin1 of R65 (since it's close to R63 this would keep my wires a little neater, anyways) -- or should I draw it from somewhere specific? Just want to be safe/sure/do it right

stinki
 
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Re: Adding LED indicators to switched mods

Post by stinki »

OK well I've got my homemade LED pushbuttons working fine, and I don't hear anything funny going on -- guess I was just being paranoid that I'd cause some subtle and frustrating issue (saw a few posts about issues when taking power from certain points) -- hurray

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altitude
 
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Re: Adding LED indicators to switched mods

Post by altitude »

sorry for the late reply, the 5V rail is exclusive to the digital section so tapping it wont have an impact on anything analog related..

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