rechargeable pack for 9v detectors

[machineman]

This is a new pack I am building of 9v detectors. I got tired of buying 9v battery at $2 each. This pack should be good for about 2000 charges. That adds up to about 3000+ normal 9v batteries. Lots of savings. It adds very little weight and requires very little work to install. Its a 750 mah pack and after a few test runs it stays above 9v for about 15 hrs. in my Silver micromax. It starts at 10.9v and quickly (less than an hour) drops into the 9v range and stays there for a long time. I spoke to some very knowledgeable engineers on the subject and they said the voltage was no problem. It works on all my Tesoros and my GBP. Here is a video I made of it. https://www.youtube.com/watch?v=HTWd15OgcHo

 

[tabman]

Your mod has gotten me to thinking about doing a mod to another brand detector that own (AT Pro) which has 4 AA batteries in front of the hand grip which makes it very nose heavy when using the larger coil. Doing a mod and placing the batteries back towards the arm cup will better balance the detector. My mod won't be waterproof, but I don't use it in the water anyway. I guess if you wanted to make it waterproof you could drill a hole in the battery cap holder so you could pass the wires through and then seal it. I'm just going to use some black duct tape to hold the battery holder in place to see how everything balances out first and then go from there if I want to.

I'll probably just use a 4 AA battery holder for my mod and use the the rechargeable batteries that I already have. I might put 4 AA batteries in the shaft later on.

Thanks for sharing.

tabman

 

[finnfoto]

Has me thinking he's reading my mind. lol I was jsut getting ready to venture over to radio shack and pick up a RC.Car rechargable battery and plug to install in my Detectorpro Landpro. .lol


Good minds think alike I see.

 

[MarkCZ]

This is a great idea!
But, all the modern detectors that I'm aware that operate on a 9 volt power source actually operates at 5 volts, all voltage above 5volts is regulated down to 5 volts. So, a 9 volt battery has 4 volts to run from before it drops below the actual operating voltage of 5 volts!
Many people think that detectors are like flashlights in that they get weaker (dimmer) as voltage drops. Or to say, if it runs on a 9 volt power source and the battery drops to 7 volts the detector loses performance, if the electronics is working as they should this shouldn't happen.

In any case with your mod there should be WAY more capacity then any 9 volt battery, but its not so much about the voltage but rather the higher milliamps.

Mark

 

[machineman]

I know that almost all the modern detectors work on 5v. The interesting thing is that a Tesoro like my silver will beep about 5 time with a normal 9v cell when new and at about 7v-8v only one time. I dont know why this is but that has been my observation. It just seemed like I was always changing batteries. So I did this. Thanks for the comments.

 

[BeyWolf]

The 5 volt regulator circuit needs at least 7 volts going in to get 5 volts out (7.5 volts works better).
When the battery drops below 7.5 volts, the regulated 5 volts is less smooth and dependable.

 

[machineman]

The 5 volt regulator circuit needs at least 7 volts going in to get 5 volts out (7.5 volts works better).
When the battery drops below 7.5 volts, the regulated 5 volts is less smooth and dependable.

That explains a lot. Thanks.

 

[goldfinder2pro]

so ,am i right in thinking you are using li-ion 3.7 v batteries?

 

[finnfoto]

Machineman. I like the idea. have you ever considered throwing in a similar rechargable like on the Whites TDI. ?


I been contimplating doing this like on the detectorpro underwater. Bit pricey tho so I have seen other alternatives just the same.

 

[RockRaven]

Great information all around on this post. Really interested to know just how much voltage the standard 5v circuit can handle without burning out or reducing service life, and if all battery types would be equally safe for the system to operate on. To be specific, would a lithium ion battery at 12v work for a 9v machine with the 5v regulator circuit?