leds

[rhdwave]

Hey all, quick question: will an led connected solely for the purpose of telling whether the effect is on or off effect the sound of the effect itself or the volume?
I breadboarded a booster and it seems to have an effect when i have it connected to the battery.  Or is this simply a breadboard issue that will resolve once the pedal is in an enclosure?

Much thanks!

[John Lyons]

The Indicator LED usually is not in the circuit... It uses ground and power from the power source but it shouldn't be in the signal path.
Can you show us the schematic you are using?

[rhdwave]

thanks for the response.  I don't have the circuit right here with me as i'm not at home, however the only part that i think might be considered in the circuit is the power connection.  Since it's on a breadboard and i'm using a battery, i have the positive of the battery going into pin6 of an lm386 opamp and then i used a jumper wire to make a connection to the 3pdt switch which then i believe goes to the resistor before the led located elsewhere in the breadboard.  does this sound correct?

[redeffect]

Maybe it's drawing too much current; creating a V drop; thus affecting the units performance. Just a guess...

[aziltz]

i don't mean to insult anyone's intelligence with a simple question but, is there a resister before the led, to limit the current?

[redeffect]

Should be. Trace it back and let us know its value. Also, what is the V at pin 6 when the effect is on? How about when its off?

[rhdwave]

Voltage is the same with the led connected or disconnected: 8.46.  I don't know maybe it's just my imagination with the difference in output.  I don't think so, but i can live with it.  Thanks for all the help though.  I appreciate it

[rockgardenlove]

I had this issue with a fuzzface...just make the LED resistor value higher and it was fine...for me at least.

[gez]

Is there a large cap across the rails to bypass the internal resistance of the battery?

[rhdwave]

I'm not sure what u mean by across the rails, but i have large cap between the battery and the v+ (pin6)input of the opamp

[gez]

I'm not sure what u mean by across the rails, but i have large cap between the battery and the v+ (pin6)input of the opamp

I meant a cap between +9V/whatever and ground.  I also thought you might be using a BJT booster.  Might help if you posted a schemo, just to make sure everything is wired up ok...

[Joecool85]

wait...if you have a cap between the positive on the battery and V+ on the circuit, that will kill DC power to the circuit...

[rhdwave]

I've got everything working now.  Thanks for all the responses.  just to clarify, the cap was filtering some noise from the power supply, doesn't seem to effect the voltages, not sure if it should or not, but seems to work.  The project was Brian Wampler's clean boost, but i added a switch to change between input caps.  i'd post the schematic here, but i can't seem to copy and paste it as it's a pdf file.  One other question i had if anyone has a possible answer re: leds as well:

What method do u use to secure the led in the led holder, i have a large led blue that is sitting in a suitable holder, but, i had to bend the leads just to get it so that it wouldn't move very much.  Also, does anyone here connect the led directly to a resistor and then the resistor to the switch or is connecting wires from the led leads to the resistor on the board a better way to do it?

Thanks again for all the responses!

[Joecool85]

I normally solder the resistor right on the leg of the LED.  Also, for power filtering it would look like this:

Battery postitive ------x----V+ on schem
                                l
                            + on cap going toward battery
                            - on cap going to ground

[rhdwave]

Yes that's how i have the power filtering.  Next time i'll try soldering the resistor right on the led leg.  It might be easier.  Thanks