EH LPB 1

[geekmacdaddy]

Hey Y'alls
Where should I attach the POS lead for a battery on this 'ole thing?
Thanks
Jeff

[jimilee]

According to the schematic, power comes in at the 430k resistor (R1) https://www.coda-effects.com/2015/09/lpb1-mini-pcb.html?m=0


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[geekmacdaddy]

Yeah, that's the problem. This has no 430k resistor. It only has 4 resistors, one is 390k, (could that be the one?), a 10k off the output jack, a 910k off the input jack, and a 100k.
thoughts?

[mauman]

Where the 910k and the 10k join is where your V+ should connect. 

[geekmacdaddy]

Where the 910k and the 10k join is where your V+ should connect. 

Thank you!

[geekmacdaddy]

ok. the 10k doesn't connect to the 910k. it goes from jack to one side of the .1uf cap with the collector of the 2N5088.

[geekmacdaddy]

The 910k hits a 100k and the Base of the 5088. other end is on the input jack

[NorthCoast]

It only has 4 resistors, one is 390k, (could that be the one?)

Is that actually a 390R coming off of the emitter?

So:

910k voltage divider resistor, between base and v+
100k voltage divider resistor, between base and ground
10k  collector resistor, between collector and v+
390R emitter resistor, between emitter and ground

Like mauman said, the 910k and the 10k should connect to v+

[geekmacdaddy]

It only has 4 resistors, one is 390k, (could that be the one?)

Is that actually a 390R coming off of the emitter?

So:

910k voltage divider resistor, between base and v+
100k voltage divider resistor, between base and ground
10k  collector resistor, between collector and v+
390R emitter resistor, between emitter and ground

Like mauman said, the 910k and the 10k should connect to v+

Thank you North Coast.
Correct. 390R. It's working but there is no boost. Vol control works when on/off switch is engaged, there's a slight change in tone (ala typical booster) but the max vol is unity. Thoughts?
Thanks for the help
Jeff

[NorthCoast]

Hmm...

What voltages do you have on the transistor?

Maybe something wrong with the pot?

[jimilee]

Transistor maybe shot, it looks like it's cooked pretty good.


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