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Re: Help with EH LPB-2

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8/15/2000 10:19 PM

Re: Help with EH LPB-2

Sheesh,

The other two resistors are a 10K coming off of the input jack and a white/red/white/gold resistor off of the output jack. The only place they are connected is at a black semi-cylinder (?) with the #s & letters 8~CC 239 on it. The other resistors are also connected to this. There are 3 seperate wires going in to it.
Thanks for your time Aron, I'm sorry I don't know how to be clearer.
Phil

8/16/2000 1:23 AM
aron	Phil, Lets work the other way. Here's the pinout of the BC239 (i.e. NTE 123ap FLAT side up) http://www.nteinc.com/graphics/diag9a.gif When looking at the flat side, the collector is on the right. Now follow this leg - it should be connected to a resistor. That resistor in turn should be connected to another. That's where the wire goes. Let me know how it goes.

8/16/2000 1:58 AM
Phil	Aron, The resistors off of that leg are connected at the on/off switch, middle lug. that was originally where you said it should go. It doesn't seem to work when I connect it there. Phil

8/16/2000 4:27 AM

Please describe the switch again. Please tell me everything that is immediately connected to the switch. What resistors are connected to the what lugs of the switch? You might as well explain the whole circuit already :-)

:-)

In order for the circuit to work, the collector is connected to a resistor which in turn is connected to 9V. If this connection is not made, the circuit will not work correctly. If course the switch needs to be ON as well for anything to work.

Thanks,

Aron

8/16/2000 11:41 AM
Petri Junno	Could it be that it is a positive ground (PNP) version. (We all know how EH made the stuff: From cheaply available parts.) Then the positive end of the battery would go to the ground. Remember to use fresh batteries. You might have short circuited the battery and emptied it... -Petri

8/16/2000 1:04 PM

Hi Aron,
Sleep beckoned. Here's the blow by blow on the switch. The - from the battery is connected to the top (outside) lug of the switch. The middle lug has an orange/white/red/gold resistor attached that is comming off the right leg of the transistor. Also attached to the middle lug is a red/black/yellow(i think)/gold resistor. This is soldered to a green rectangle(?) with 154K 100V on it and a white/red/white/gold resistor. These then go to the middle leg of the transistor. Nothing is connected to the bottom outside lug of the switch.

Thanks,
Phil

8/16/2000 1:49 PM

As I said on my previous post, I think you should try connecting the + side of the battery to ground.

Ground is something where lots of stuff connect to. This includes the case of the device, one wire from the volume pot and usually one wire from both jacks. Sometimes all of these don't connect to a single point but they always connect somehow. (Note that the metal case is a conductor too...)

And then again... I might be completely on wrong track... This aplies only if it is a positive ground device...

-Petri

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