12 volt Tesoro running on External Battery

[trueblue]

I am considering a small mod on my Tejon , I have a 12volt 7Ah Battery am thinking it should be ok to hook up as an external ..Ive been running NiMH 2900 mAh rechargables .....I know little of electronics but as far as I can find out through google searchs ...As long as the battery is 12 volt the Amp's wont affect the detector in any other way other than providing the required amount of power with a run time depent on the battery Amp rating ...the higher rating = longer runtime .....lower rating = shorter runtime

most battery packs are specified in mAh, which is simply milliamp-hour. To convert amp to milliamp, all you have to do is multiply amp by one thousand. To convert milliamp to amp, simply divide milliamp by one thousand.

.I got quote above and done the math an came up with the following
the external battery I have is 7Ah converted = 7000 mAh

the Nimh at 2900 mah converted = 2.9 Ah multiply by x8 batterys = 23.2 Ah

so the external battery has a lower Ah than the 8 x Nimh batterys ....... do you this is worked out properly as in can I just mutiply the mAh ratings by the amount of Nimh's and come up with the correct mAh rating ? Electronic's can be tricky so Im not sure here

Another question is with the Tejons battery compartment being split in 2 halves with a battery pack loading into either side ...would I be able to wire up my external battery into just 1 compartment ? Im figuring the 2 battery packs just feed into the 1 power line to provide the 12 volts ..not 2 separate power lines like that of a for examle Bounty Hunter where one batterys suppling power to the VID and the other to the rest a the detector ? can anyone inform as to your opinion on whether this will work ok ....I dont want to cause any problems a possibly blow the detector with to much power or wired wrong ...any advice is appreciated.....Baz

 

[dmckee17]

From what I understand you could hook it up to a 12v car battery if you wanted to, as long as you give it 12v. The ah/mah is just going to determine the length of battery life.

 

[kd8hf]

Just be careful when your wiring it up. The two normal battery packs could be wired in series or parallel, not sure which, but depending how the normal configuration is the voltage could be something other than 12VDC. Gary

 

[TomekV]

the external battery I have is 7Ah converted = 7000 mAh

the Nimh at 2900 mah converted = 2.9 Ah multiply by x8 batterys = 23.2 Ah

so the external battery has a lower Ah than the 8 x Nimh batterys ....... do you this is worked out properly as in can I just mutiply the mAh ratings by the amount of Nimh's and come up with the correct mAh rating ? Electronic's can be tricky so Im not sure here

Hello bluetrue.

If the 8 x Nimh are connected in series (+ to - ...), we receive 9.6V and 2.9Ah

If the 8 x Nimh are connected parallel (+ to +, - to - ...), we receive 1.2V and 23.2 Ah

...I think

 

[trueblue]

thanks for the help Guy's ...it seems the external battery should be ok ...... the big question that Im now very unsure of is whether the batts are wired in series or parallel ??? Ive got no idea ? does anybody know for certain ???

 

[tvr]

My concern with the questions you are asking, is that you haven't yet learned enough on this topic to tell how the battery wires are hooked up originally and how to make sure you wire or build a battery pack for the same end result. If you are in doubt on this one, I'd recommend leaving it alone until you learn on something less expensive than a hundreds of dollars detector.
Respectfully,
tvr

 

[BarberBill]

My question is are you having to replace the batteries often enough for this to be a truly worthwhile project? While I'm not operating a Tejon, all my detectors get many hours from good quality alkaline batteries and you mention you have been using rechargeable so you don't need to buy replacements regularly, so is it worh the effort?
HH
BB

 

[trueblue]

My concern with the questions you are asking, is that you haven't yet learned enough on this topic to tell how the battery wires are hooked up originally and how to make sure you wire or build a battery pack for the same end result. If you are in doubt on this one, I'd recommend leaving it alone until you learn on something less expensive than a hundreds of dollars detector.
Respectfully,

yeah ya spot'on there trv thats excellent advide I got no idea even so I was just about to try'n hook it up to 12volt external and take the risk ....but nah not now you've changed my mind for the time being ...I will keep looking into it and hopefully it will be possible ..I'd kick myself it I damaged the Tejon

My question is are you having to replace the batteries often enough for this to be a truly worthwhile project? While I'm not operating a Tejon, all my detectors get many hours from good quality alkaline batteries and you mention you have been using rechargeable so you don't need to buy replacements regularly, so is it worh the effort?
HH
BB

Bill it aint that I need to change the batterys alot ,the NiMH's last a coulpe a days pretty well running the detector all day ... Its more of a convenience if I dont need to return home to charge the batterys .. I spend alota time in the bush away from home and quite a distance to any towns hunting and detecting sometimes a week or more at a time ......so I always carry a few drycell 12 volt batts with me to run other gear , I figured if I could get the Tejon to run off a drycell it would probly be enough to power it for a week of detecting if not more .....alkalines are expensive for instance 8 energizers cost $ 16 here in my home town ...I cant really aford that so I always lookin for way to save a few $$ and I could stay in the bush for longer periods without hav'n to worrie about batterys

cheers Baz

 

[Ism]

I am considering a small mod on my Tejon , I have a 12volt 7Ah Battery am thinking it should be ok to hook up as an external ..Ive been running NiMH 2900 mAh rechargables .....I know little of electronics but as far as I can find out through google searchs ...As long as the battery is 12 volt the Amp's wont affect the detector in any other way other than providing the required amount of power with a run time depent on the battery Amp rating ...the higher rating = longer runtime .....lower rating = shorter runtime

most battery packs are specified in mAh, which is simply milliamp-hour. To convert amp to milliamp, all you have to do is multiply amp by one thousand. To convert milliamp to amp, simply divide milliamp by one thousand.

.I got quote above and done the math an came up with the following
the external battery I have is 7Ah converted = 7000 mAh

the Nimh at 2900 mah converted = 2.9 Ah multiply by x8 batterys = 23.2 Ah

Current doesn't multiply when batteries are in series like voltage does. If I'm correct, it should stay the same. When wired in parallel, the potential current increases, but voltage stays the same

Another question is with the Tejons battery compartment being split in 2 halves with a battery pack loading into either side ...would I be able to wire up my external battery into just 1 compartment ? I'm figuring the 2 battery packs just feed into the 1 power line to provide the 12 volts ..not 2 separate power lines like that of a for examle Bounty Hunter where one batterys suppling power to the VID and the other to the rest a the detector ? can anyone inform as to your opinion on whether this will work ok ....I dont want to cause any problems a possibly blow the detector with to much power or wired wrong ...any advice is appreciated.....Baz

You cannot supply power to one side. The battery packs are wired in series. 2 battery packs with 4-1.5v batteries= 6v on each side. You will have to open it up and find where to supply the12v power by following the battery leads.
You should find where the 6v battery terminals are tied together to create 12v. Good luck, your external battery should last well over twice as long and more likely 4 times that of the AA batteries.
[/quote]

 

[tvr]

trueblue,
ISM is correct with the wiring.

I'd recommend picking up an introduction to basic electronics booklet or possibly finding an on-line introduction course. Then get a Volt / Ohm meter and carefully probe the battery connections on an inexpensive radio, and a few other low voltage things and then carefully probe the battery connections on the Tejon and re-read where ISM says:
"The battery packs are wired in series. 2 battery packs with 4-1.5v batteries= 6v on each side. You will have to open it up and find where to supply the12v power by following the battery leads.
You should find where the 6v battery terminals are tied together to create 12v."

When it all starts to make perfect sense, then make the decision on how bad you want to do it. Get some spare pieces of wire and practice soldering on those before trying anything on the detector battery wires. If it doesn't all add up, and doesn't feel good when practicing connecting wires, defer until it does.

In any case, enjoy your Tejon!
Cheers,
tvr

 

[trueblue]

thankyou all for the sound advice , its on the backburner for the time being , packin me gear an Im headin away for a few days to enjoy my Tejon

"HH"
cheers
Baz

 

[BarberBill]

It's easy to find chargers than plug into the cig ligher socket on your vehicle. That would solve the "going home" problem.
HH
BB

 

[rmptr]

My battery life has been outstanding with anything but the cheapest batteries available.

I've considered making up a long pigtail to reach back to underneath the arm cuff where I could zip tie a larger pack.

So far, it hasn't been an issue for me, though.

Should work well, though.

Good luck !

 

[grumpyolman]

And if you are in the brush and there's any sunlight, you can pick up a solar charger fairly cheaply now. Leave a pack at camp with the solar charger and you can be out in the brush for months and not have to worry about charging them from the vehicle or another source. Jim

 

[trueblue]

great tips there fellas its appreciated