EHX LPB-1

EHX LPB-1

Project description

The well-known LPB-1 clean booster pedal from Electro Harmonix based on the schematic from Beavis Audio.

Bill of materials

Resistors
R1: 1M
R2: 10K
R3: 100K
R4: 390R
Potentiometers
R5: 100K Log (A)
Capacitors
C1: 100nF
C2: 100nF
Transistors
Q1: 2N5088
2 trace cuts

List

Click here to see the bill-of-materials as a list or download it as a comma separated values file (.csv).

Code

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Comments

Mis-bias problem...I think

I've built the circuit and am 99.9% sure that theres no problems with lumps of solder crossing the tracks or anything and that all parts are correct and in the right place but what happens is this. . . .

...In order to get some noise out of my guitar I have to hit the strings quite hard and even then theres a delay between hitting the strings and hearing it.

I've had a look round the interweb and it seems that there is a mis-bias somewhere. I've swapped the transistor but i'm still getting a horrible sound.

Any ideas ?

Thank you...I love this site :-)

Can you post the voltage of

Can you post the voltage of each pin of the transistor you used?

Voltage

Sorry but i'm somewhat a newbie with all this and i'm not sure how to do it.

I've got a cheap DMM but am a little unsure what to do with it

Thanx

Dean

Capacitors...

Just a quicky ! It seems i've run out of caps, can I use 100v capacitors ? I know its a little restrictive due to there size but its just to test it.

Thanx

100V

Jep, no problem (except for the size) ...

Works!

My first pedal I built. Works finally! Good overdrive sound if you crank it all the way up.

Transistors Question

Can I replace the 2N5088 with 2N2222 or 2N3904 without any issues?

I must say your site rocks!!!!!!!!!!

new at this,

whats a gnd?

GND

The ground connection...

2N4401

Yep, the 2N4401 works fine.

Transistors

Can I replace the 2N5088 with a 2N4401 with no problems?

Just to help clarify...

Just to help clarify, the red square with red dots indicate that the PC board strip electric connector is broken, right?

exactly

exactly

I built it and it works.

I built it and it works.

Awesomeness! This site is

Awesomeness! This site is great and the layouts are awesome! Thanks a lot!!!

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