Old Pedulla batteries going flat real fast.

[FatAndy]

My 20 year old Pedulla is running through 9V batteries like crazy (flat in a week!), I am using expensive alkalines.
It has all original parts and soldering, maybe something is shorting out? Any ideas before I take it in to my expensive fixit man?

 

[4to5to6]

Got me on this one... Presuming you unplug the chord from the jack when not playing batteries should last a long time. I'll also presume everything is still working like normal (controls, noise level, output, etc.) I believe all Pedulla pickups are the passive (2-wire) type so no extra power drain here. Hmm. Make sure nothing is visibly shorting out inside. Make sure the jack is not shorted therefore not disconnecting the battery when unplugged. A partially shorted volume or blend pot could drain a lot if power to ground but output would be noticably decreased. Take some readings with a Keith McMillen Batt-O-Meter which senses current draw and voltage and gives you an estimate of hours of playing left. For example, if the meter says you have 10 hours left and you play for an hour and they are dead or if you test the battery out of the bass with the meter and it shows 100% then test them installed and it shows an hour left you know you have an extremely hi power drain. I guess you could also test with the blend turned to one side then the other to isolate individual pickups. Hmm. Sorry. Got me on this one. I did have this happen to me once with an Aguilar OBP3 pre and installed a new pre. I did find a bad volume pot and cleaned up some other wiring and made sure pot leads weren't touching the grey shielding paint (check this as well) so never did know for sure what exactly fixed the problem.

 

[brianrost]

Make sure the jack is not shorted therefore not disconnecting the battery when unplugged.

+1

Check for corrosion or dirt on the jack contacts

 

[FatAndy]

I will check it out. I live right on the beach.....the salt air might be the problem, even though this bass spends 99% of the time in a case.

 

[SGD Lutherie]

Sometimes on these basses, the jack rotates and touches the conductive paint. If the battery (-) lug touches the paint the battery stays on.

Spin the jack back around and add some conductive tape.

 

[4to5to6]

+1

 

[FatAndy]

To be honest, the batteries are running down so quickly, I think that it is not just that the battery is getting normally used (like when a bass is left plugged in continuously) I think it might be something else.

Cheers to everyone!

 

[4to5to6]

So it doesn't go dead just sitting there unplugged then? But goes dead quickly when playing it?

Best guess then is one of the pots has shorted to ground (the gray conductive paint). Visually check that one of the pot leads isn't touching the paint. It could be internally in the pot. Overheating when soldering can cause this.

Sadly, it could be the preamp or pickups but I can't see this happening with out affecting the tone and volume output in some way.

I see you are on the Sunshine Coast. I live in Burnaby close to New West. PM or email me. I would be happy to take a look at it for you. No trouble shooting or labour charge and parts at cost for a new TalkBass member and Pedulla owner. You can compare your MVP directly side by side with my '90 Buzz.

 

[4to5to6]

Email sent.

 

[BillyIVbass]

Email Pedulla. I've contacted them before and got prompt, great customer service and I don't even own one of their basses!

 

[4to5to6]

+1

Pedulla contact info:

Email: [email protected] (quote model & serial in subject line)

Christine is awesome. She's worked for Michael for 20 years!

Tel: 1-781-871-0073

See [Invalid or Expired Link Removed]

 

[FatAndy]

So it doesn't go dead just sitting there unplugged then? But goes dead quickly when playing it?

Best guess then is one of the pots has shorted to ground (the gray conductive paint). Visually check that one of the pot leads isn't touching the paint. It could be internally in the pot. Overheating when soldering can cause this.

Sadly, it could be the preamp or pickups but I can't see this happening with out affecting the tone and volume output in some way.

I see you are on the Sunshine Coast. I live in Burnaby close to New West. PM or email me. I would be happy to take a look at it for you. No trouble shooting or labour charge and parts at cost for a new TalkBass member and Pedulla owner. You can compare your MVP directly side by side with my '90 Buzz.

I live on the Sunshine Coast in Australia. I have corresponded with Christine (trying to find out the name of the custom finish on my Pedulla), she is wonderful!, and I think Michael makes some of the most brilliant, underrated bass guitars on Earth.

I am going to take this bass to a pro for a diagnosis and fix... he is expensive, but worth it for this beautiful bass! Thanks for the ideas, mate

 

[4to5to6]

That's funny... Same place name but wrong country! Sure you don't want to come to Canada for a bass tune up

Cheers!

 

[4to5to6]

One more quick thought on this...

Try to keep the original Pedulla P/Us and preamp as they are custom voiced by Pedulla and Bartolini to work with the MVP.

 

[mech]

If the jack or wiring is not shorted and keeping the preamp on....

Most preamps have an isolation diode and storage capacitor at the positive voltage input. The isolation diode prevents damage if the battery is hooked up backwards and the storage capacitor smooths out the current demand on the battery. I would get a tech to check for and replace the storage cap. Probably a 100mF@25 VDC. A leaky cap in this position will run the battery down but only when the pre is on. Seen it a time or two.

mech