I was wondering if there are anyone out there that can help me with this issue.
This bass that i've got doesn't produce any sound, and i have a feeling that there's something wrong with the pots. I've tried measuring them with a multimeter and the results produces are weird?
500k A pot @ 4M resistance shows: 0.010 on multimeter
50K B pot @ 400K resistance shows: 29.1 on multimeter
other 50K B pot @ 400k resistance shows 29.8 on multimeter
We have questions for you.
What kind of bass?
Did it just happen?
Well if you have the wires exposed just by pass the pot with a short temp jumper wire.
This will make it full volume. Then you will know. You might have to jump both depending how its wired.
What setting is the multimeter set to? Are the "at 400K" or 4M your settings, in the DC resistance section?
Your readings indicate 10K, 29.1K, 29.8K on the 3 pots respectively. I assume you're measuring between the two outside pins of each pot, in circuit. My guess is this is an active bass with passive pickup(s) since there are 50K pots? You can't accurately measure the resistance of a POT while it's in-circuit since the pickups and other components will greatly affect your reading. My best recommendation is to connect the pickup directly to the output jack and disconnect any other circuits to make sure the pickups are OK.
I know what he's saying...
500k is the pot rating. Multimeter is set to 4M Ohm range and it's reading 0.010 or 10k Ohms
50K is another pot rating. Multimeter is set to 400k range and is reading 29.1 or 29.1k ohms
another 50k pot reads 29.8k
And, just to make sure, you're reading across the outside terminals?
It sounds like your 500k pot is toast. Shorted out.
The 50ks are reading low too, but significantly less bad than the 500k.
500K pot is not necessarily toast. If this is a volume pot, still connected to a pickup with DCR of 10~15K, with volume up, the reading will come out to 10K. You can only accurately test individual components when they are isolated from the circuit.
OH, that's a good point. I assumed they were isolated. They should be isolated :-)
wouldnt there be some parallel resistance, what with the pickups themselves and the rest of the circuit?
read the last posts, ed.. :rollno:
Yeah. that's what i meant.
It's a yamaha rbx765a.
I did not isolate it. It was soldered on to a small circuit board.
I acquired this bass from a mate and apparently its been like that for a year and he just never got around to fixing it.
so, how do i go about trouble shooting?
do i have to de-solder every pot and test it? or is there another way around?
No sound is very rarely an issue with pots. Sounds like there is a cold solder joint, or a preamp issue.
That's a good point actually--all this business about the pots and the multimeter was kind of missing the boat.
OP, have you changed the battery? Does it really make "no sound" or is it very quiet, or is there a hiss or hum? If you wiggle the various wires and parts while the bass is plugged in, are there any crackling, popping, or other intermittent sounds? Any noises when you plug the cable in/out?
Haha. Please excuse my noob-ness. First time i'm dealing with these electronics. :(
I put in a new battery, and plugged it in. And there isn't a sound at all. Shook the wires and components a little, still nothing. There is that normal pop you get when plugging it in and out.
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