Battery Question reverse protection?

[justruckn]

Do any of the nine volt detectors protect against accidental battery reversal?

 

[Coinseeker 78]

IF you have a clip on cap should be no problem because they only go on one way. The battery hookup that just insert the batteries into a slot can be reversed. I have done this but it did not destroy the detector, Of course the detector did not work with reversed battery hookup.

 

[justruckn]

I have seen equipment where some one forced a nine volt battery into a slot backward. That will crush the battery case but if you push hard enough it can be forced in. If the equipment does not have a protective diode the electronics can be destroyed.

These diodes have the name "Idiot diodes."

I wondered if anyone has a circuit diagram and if there is this protection?

 

[twalton]

My nephew put one in backwards in his Discovery 3300 and left it that way for 3 months. He complained to me that the detector did not work very well, would not even find a nickel on a bare floor. The first thing I always do is put in fresh batteries to see if that cures the problem, and that's when I found the reversed battery. Turned it around and now the detector works just fine, no permanent damage as far as we can tell.

HH, twalton

Tracker IV
Pioneer 202

 

[BH-LandStar]

The detector actually worked with reverse polarity??? I am shocked!!!


HH,

BH-LandStar

 

[dobbie]

although for some reason one battery will come loose somehow and my MD will not work so i have to put a piece of bark in between the battery and the plastic clip to hold it down....should i send it in for repair or just keep using the bark trick.

 

[twalton]

The owner's manual for the Discovery 3300 recommends using a thin cardboard shim between the clip and 9v batteries if loose contact is a problem. Reminds me of using a match book under an 8 track tape to get it to play! How old am I!

HH, twalton

 

[BH-LandStar]

If that is the only thing wrong with the detector, I would use the cardboard, or even a piece of foam rubber as a shim...better than paying the shipping for a simple problem...


HH,

BH-LandStar

 

[justruckn]

Dobbie......Look into the battery compartment and see if there are compressible battery contacts. They should look like a bent piece of metal. If they are there you can reach in with a probe or pick and pull out on the bent contact restoring it to the original position.

Be careful and only pull slightly. If the bend is weak it might break at the bend. It that happens you will have to devise a new contact. Parts might be available or you can buy a battery box from a parts company and steal the battery springs or contacts from it.


I am still interested in a schematic if any one has one.

 

[dougmoore34]

My Discovery 2200 had the loose battery issue. Solution: a strip of bicycle inner tube.
I too am surprised that a detector ran reverse polarity, but that just shows what I know.
Doug in OR

 

[silversmith]

My question is did "HH" say 8 track or "4 track" ?

 

[twalton]

Back in 1966 my brother had the 4 track player in his first car, an 1959 english ford 2 door sedan. I was just 7 yrs old and thought that car was the coolest!

HH, twalton