adding an LED

[retard_robbie]

first - i dont know a whole lot about electronics

this is regarding the beginners project called "electra distortion". i know how the dual throw switch is connected - the middle pair of connectors go to the two jacks, one pair is bridged (the bottom two) and the other pair connects to the circuitry. what i want to do (and i presume i cant) is just put an LED somewhere in the circuit - so that it will come on when the effect is not bypassed. will this work? will it need to go in parallel somewhere? i cant see a problem, so i thought to ask first rather than mess up the circuit.

also, i havent finished it yet - it looks like putting in the audio jack in the input will connect the circuit and turn the thing on, and when it is bypassed with the dual throw switch the battery will not be in the active circuit (just the little wire bridge). is this correct?

one more - if i get a socket for a 9v adapter, can i simply swap this for where the 9v battery goes? if so, what is the size and polarity etc. of th socket?

thank you

Rob

[R.G.]

first - i dont know a whole lot about electronics

We can help with that, and your questions as well

First, go read "The Technology of Bypasses" at GEO - http://www.geofex.com

True bypass with an LED indicator needs either a 3PDT switch or a Millenium Bypass circuit. There's a lot of info here on the forum on those, just search on both terms.

one more - if i get a socket for a 9v adapter, can i simply swap this for where the 9v battery goes?

Yes, given that you wire it as mentioned below.

if so, what is the size and polarity etc. of th socket?

You want a DC power socket, I believe 5.1mm barrel and 2.1mm hole, and you need to get an isolated DC adapter. This is because 99% of effects DC jacks use the outside barrel as positive, and it must be isolated from the enclosure, which is grounded. Mouser electronics sells an isolated DC jack for about $1.

[retard_robbie]

ok i read the guitar effects webpage article. i dont understand what a jfet is, so i am looking at the true bypass thing before that in the article. i think i see where the dpdt switch connects, and where the bridge changes to etc. but what about the LED circuit? one of the things is a transistor, but what values are the resistors (or how am i supposed to work them out)? and do i need a second source for the +9v on the LED circuit

also, i still dont understand why you cant just put an LED into the "FX" circuit

sorry if these are stupid questions - this stuff is harder than i expected

Rob

[fixr1984]

but what about the LED circuit? one of the things is a transistor, but what values are the resistors (or how am i supposed to work them out)? and do i need a second source for the +9v on the LED circuit

also, i still dont understand why you cant just put an LED into the "FX" circuit

sorry if these are stupid questions - this stuff is harder than i expected

Rob

Did you check this out?http://www.generalguitargadgets.com/diagrams/switch_lo_dpdt_mil.gif This one gives you values as well as how to wire it up.
As R.G. said, for true bypass you would need one of his two suggestions, reason being is that you need power to run the LED and without one of the 2 methods you have no way of cutting power to the LED with out cutting power to the circuit which would then kill the circuit. No power to the circuit=no sound at all.