"ExtraLife" simple battery mod for single 9v Tesoros

[SilverFinger]

"ExtraLife" simple battery mod for single 9v Tesoro's

The "ExtraLife" battery mod for any Tesoro the uses a single 9v. A simple gadget that will increase your battery life 3-4 times and not void your warranty.
I stripped the metal casing off a dead 9v battery, removed the terminal top and soldered wires to the bottom of them. Then I hot glued the terminal ass'y back to the top of the battery. I only used the battery for a placeholder. I ordered a 6 cell AA battery holder which will mount to the bottom of the arm cuff using good quality double sided foam tape. I'll then run the wiring along the S-pole and fasten the wires with some zip ties.
My biggest gripe about the single 9v power source is battery life and of course, cost. This will allow you to use less expensive AA alkalines to power your single 9v Tesoro machine and in theory should at least triple the battery life while adding negligible weight to the featherlight machines. I already tested it in 'theory', I just haven't gotten the battery box yet. I'll post some pics when complete...

 

Amazon Forum Fav 👍

Cry Of The Eagle: History And Legends Of The Cherokee Indians And Their Buried Treasure - Grab it through Amazon!

[TallTom]

Interesting idea. If you're happy with the results, good for you!

However, those six AA batteries are considerably heavier than one 9V.
I'd worry about the wear and tear on my shoulder and elbow, which are
both starting to age rapidly (along with my other body parts).

My solution was simply to buy a four-pack of rechargeable 9V batteries
and a quick charger. They work fine, although they only last about half
as long as an alkaline 9V in my quick-and-dirty comparisons. But I simply
keep a spare charged battery in my pocket, so I'm ready to switch quickly
and continue detecting. The rechargeables pay for themselves pretty
quickly compared to alkalines. When bought online in a four pack, they
were about $3.50 or $4 each, as I recall. (That is, about $14-16 for
the four pack.) And even lighter weight!

--Tom

 

[luvsdux]

My single 9 volt Tesoros are so easy on batteries when using good quality alkaline I'm not even tempted to use rechargeables, let alone try to jury ring AAs.
luvsdux

 

[SilverFinger]

I'm burnin' through 9v's on the Vaquero. Down to 3 beeps in what seems like 5-6 hours of hunting with Duracell alkalines, wearing phones too. I have to wonder if the type of headphones make a difference. Resistance and such. That's what inspired the 6 AA pack. You don't even notice the weight when mounted on the bottom of the arm cuff.

 

[atomicscott]

I'm burnin' through 9v's on the Vaquero. Down to 3 beeps in what seems like 5-6 hours of hunting with Duracell alkalines, wearing phones too. I have to wonder if the type of headphones make a difference. Resistance and such. That's what inspired the 6 AA pack. You don't even notice the weight when mounted on the bottom of the arm cuff.

I got tired of spending $7-8 for about 20 hrs or less of detecting with a single 9 volt. I now get over 20 hrs with 4 AA alkalines from the .99 cent store. More money= more gas to go detecting

 

[SilverFinger]

Completed battery mod for the 9v Tesoro....

I loaded it up with cheap Dollar Store AA alkalines (they look like Duracell knock offs) 6 AA batteries at a cost of $3.99. The pack tested new 9.27v. Hunted pretty much all day yesterday and half of the day today. Pack tested 9.22v after a day and a half hunt. Ya gotta admit, that's impressive.

Attached the 6 AA pack to the arm cuff using Gorilla glue (that BTW is some strong stuff!)

You can feel the weight, but it's negligible. Actually seems to balance better to me.

 

[atomicscott]

I loaded it up with cheap Dollar Store AA alkalines (they look like Duracell knock offs) 6 AA batteries at a cost of $3.99. The pack tested new 9.27v. Hunted pretty much all day yesterday and half of the day today. Pack tested 9.22v after a day and a half hunt. Ya gotta admit, that's impressive.

Attached the 6 AA pack to the arm cuff using Gorilla glue (that BTW is some strong stuff!)

You can feel the weight, but it's negligible. Actually seems to balance better to me.

I think that is impressive & does address an important issue. The cheaper it is to detect, the more $ you can keep in ur pocket. Great idea IMO. Tesoro should take note!

 

[TallTom]

I'm burnin' through 9v's on the Vaquero. Down to 3 beeps in what seems like 5-6 hours of hunting with Duracell alkalines, wearing phones too. I have to wonder if the type of headphones make a difference. Resistance and such. That's what inspired the 6 AA pack. You don't even notice the weight when mounted on the bottom of the arm cuff.

Just FYI, I seem to get about 5-6 hours on my Vaquero using a rechargeable 9V. I'm using Tenergy 250 mAh NiMH ones.
I also use headphones. I wouldn't be surprised if different headphones drained the battery at different rates, but I
haven't experimented with other models, other than briefly just to test if my backup headphones worked OK.

Twice I've tried alkaline 9V batteries on my Vaq. I didn't measure carefully, but I think I got
about 10-12 hours usage each time. Considering the cost of alkaline 9V batteries, that
was enough to make me buy the rechargeables. It's a little annoying to have to switch
rechargeables every five or six hours of hunting, but I feel like I'm saving money every
time I do.

Congrats to the original poster on the successful AA conversion! I'm not claiming
that using rechargeables is better, just that it's an alternative to consider. To each
his own.