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Vintage threads from the first ten years
Help with EH LPB-2
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 8/15/2000 7:47 PM |
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Phil |
Help with EH LPB-2 1st off, let me say that I know just enough to be dangerous, and sometimes not even that much. While putting the guts of an LPB-2 into a smaller case, the + lead from the battery became unattached. I CAN'T FIND WHERE IT GOES! I don't know how to read schematics so if anyone here has one of these and can explain to an idiot with his tail between his legs where to reattach it, I would greatly appreciate it. thanks, Phil |
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| 8/15/2000 8:22 PM |
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| aron |
Phil, A golden chance to learn more! OK, one way - look carefully on the board - there should be a hole (filled - maybe with a little wire sticking out) that the wire came out from. That's probably the one you need to re-attach the wire to. OK, the other way: Look for a 10K and a 470K resistor on the board. How do you find them? There are only 4 resistors on the board. Here's how you decipher the wonderful world of resistors: ------ You should be able to identify basic components such as
You should be able to read resistor values. Resistor
-------- Find out where the 2 resistors connect (i.e. touch) each other and that's where the plus lead (POWER) goes. If you look at the schematic, this becomes clearer. http://www.montagar.com/~patj/ehbsters.gif Also check out this page. http://firebottle.net/stompbox/skills.html Aron |
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| 8/15/2000 8:24 PM |
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| aron |
Awe shucks... After looking at the schematic, the plus wire goes to the on/off switch. Just look there and one of the lugs should have a wire missing or a little bit of solder left on it with strands of wire. That's where the wire goes. It was more fun when you had to search the board!  |
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| 8/15/2000 8:59 PM |
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| Phil |
Thanks for the reply, Aron. I do have a lot to learn. On the on/off switch, there is a - from the battery on 1 lug and a lug with 2 resistors soldered to it. the 3rd lug is empty and doesn't look like it's ever been used. Do I solder the + to the lug with 2 resistors? Thanks, Phil |
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| 8/15/2000 9:07 PM |
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| aron |
Hmmm..... Phil, the switch has the black wire attached to one lug and 2 resistors on another lug? OK, if you look a the switch, where is the black wire connected to, the middle or one of the two outer lugs??? Where are the resistors connected to? Inner or outer lug? Try using the resistor chart to figure our what the values of the resistors are or just tell me the colors of the two resistors. Aron |
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| 8/15/2000 9:34 PM |
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| Phil |
Aron, The black wire from the battery is attached to the upper outer lug on the on/off switch. The 2 resistors (red/black/yellow/gold-3,900 ohms & orange/white/red/gold-200,000 ohms ?) are on the inner middle lug. The bottom outer lug is empty and doesn't apper to have ever been used. Hope this helps, Phil |
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| 8/15/2000 9:47 PM |
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| aron |
You read them correctly, just backwards. The red/black/yellow is 200K, the other is 3.9K. I don't see those two in the schematic. There's a 390ohm - orange/white/brown in the there. Anyway it looks like the switch connects the NEGATIVE terminal of the battery to ground, completing the circuit - not like the schematic suggests. If you can find these two resistors: Yellow/Orange/Yellow (430K) and Brown/Black/Orange (10K) and find where their two leads connect, that's where power goes. I guess by definition, they are the other two! What are their values? Aron |
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