Battery pack for chrony

[mshm99]

I was not quite sure where to start this thread. Since many of us use a chronograph , here is a way to save money and help the environment at the same time.

Notice my sabot whacked lens on the chrony.

Radio Shack has a battery pack, that holds 8 AA's and has a 9 volt connector on the top. I recycle my AA's that are other wise worn out ( 1.1 volt or there about) . With 8 of the AA's it will run your chronograph or anything else the needs 9 volts for long time. I love a bargain,and this really is one.



mshm

[onecardchuck]

mshm99,

I am a rechargable battery guy also. Have to be with the kiddies and all there toys. You can really save alot of money in the long run going this way. Great minds think alike and thanks for sharing your find here I love it, and will soon get one.

Keep the good ideas coming.

[chuck41]

Nice idea. I use rechargeables for just about everything I absolutely can these days. Cost more initially, but save a bunch over time. The 6v rechargeable lantern batteries go in my feeders. I have numerous AA, AAA, and C cells as well. May soon get one of those Radio Shack battery holders for my chrony.

[rbinar]

8-)Maybe a good idea for some but the 8 battery pack must be unique. 8 series 1.5 volt cells makes 12 volts not 9.
Most modern day electronics will run on a wide variety of voltage inputs but what happens if yours won't?

Now I suppose it's possible the 8 pack could have 2 sets of the 1.5 volt batteries in parallel to get to 9v but it's not likely.

A better solution to me would be to buy three 9v battery connectors and connect them all in parallel.

[Harley]

When I first read this solution, I did the same math as RB; my concern is not just the 12 volt total; more importantly, I would worry about the amperage damaging your chrony ii it doesn't match that of a 9 volt battery.

Harley

[mshm99]

I am very much aware that that 8 times 1.5 = 12. Notice I said "I recycle my AA's that are other wise worn out ( 1.1 volt or there about) ". This particular gang of batteries measures out at 9.1 volts under load. Also rechargeable NmH batteries don't quite come up to 1.5 volts when fully charged . If it makes you feel better solder a jumper between the the positive and negative on the last battery slot( 7 X1.5=10.5). With DC stuff a couple volts one way or the other does not make much difference.It's the amperage that burns things up.(think of a welder). Example does the radio in your car have to have exactly 12 volts. I have had alternators in some of my cars run as high as 14 volts with no ill effects on any thing. Hook up a 9 volt transistor radio to 12 volts and see what happens. ( I'll bet it plays really well).I hooked this battery pack up 4-5 years ago ,with no ill effects. I just noticed it the other day and thought I'd share it with the board. But if you are uncomfortable doing this ,by all means,keep buying 9 volt batteries.

mshm

[raf]

Might be a good idea if you use your crony a lot but me and the number of times I use mine, well it just isn't feasable. I still have the original 9 volt in mine and have had it for several years. Maybe I just don't shoot enough

[jims]

Will my rifle shoot faster if I use 12 volts. ;D An interesting concept, you know alot more about electricity than I do.

[fitz]

Ok...I've been reading the mail on this board for a while again...on the other(first) one I was "fitzzie" for a short while...last summer and fall thru Dec.

I can clear up a few things about batteries and such since I design and build my own radio equipment as an amateur radio operator...been doing it for over 30 years...so I do know a little bit about it...my callsign is N0MF. My "thing" in ham radio is building small battery-powered high-frequency transceivers, sometimes the size of a pack of smokes... Often it is necessary to custom-build battery packs for these radios.

mshm99... Although what you are doing may work with old tired batteries that are run down, as others have said, it is risky. First of all, not all cells have the same voltage, and what you are concerned about IS the voltage. Amperage, called "current" by those in the business, is only a concern if your power supply cannot source enough. You cannot have too much current and burn something up just due to that...Ohm's Law... It is too much voltage that you need to be worried about here... AA cells, or even the smaller AAA cells can source more than a 9 volt battery. If you take a 9 volt battery apart you will find six very small cells that run 1.5 volts when new and charged.

Not all types of cells have the same fully charged voltage, as other have said. Alkalines, the older zinc/carbon type cells and lithium cells are 1.5 volts. Rechargeable cells like Nicads, Nickle-metal-hydride, etc. are 1.2-1.3 volts fully charged. You can use either, but do the math beforehand...

You "may" be able to run a 9-volt radio on 12 volts, but you may also, as we call it, let the smoke out... It is highly inadvisable...it all depends on the circuitry of the radio, primarily whether it has a voltage regulator in the circuit or not...many small radios don't...it costs more to use one. Cars have voltage regulators on the alternator BTW...very necessary.

What I don't understand is why you feel the need to use old worn out batteries...new ones are cheap! Go to Wallyworld or Costco and get a big pack of them...they last a long time on the shelf. I can't believe you are so hard-up you need to squeeze every last bit of energy out of these things...when they start to go down they can also just quit on you without warning...

You certainly can make your own external pack, but use 6 of them if they are alkalines, or do the math if you want to use rechargables...

The other thing I would be concerned about is jerking the wires off the circuit board of the chrony. Unless there is a strain relief it is easy to do...and unless you know how to solder and have the right equipment for a printed circuit board...you are going to be sending it back in for repairs... Those little wires are not designed to be flexed back and forth very much at all...and when they are they usually break where they are soldered to the board.

Sorry if I sound like a smart-ass, but I know this stuff inside out...for real...
Fitz

[Harley]

Sorry if I sound like a smart-ass, but I know this stuff inside out...for real...
Fitz

-----------------------------

Fitz, if that's what you are, then that's what we need more of around here. Thanks.

Harley

[mshm99]

I can't argue with anything you have said. You are corrrect about your defining current, however , some batteries now express their capacity in milli ampere hours,hence a better expression of potential.

As far as why use old batteries. Why re-use a plastic bag? Milk jug? Recycle ? One more use before you put it in the trash stream.

It seems pretty obvious to me that most of us use AA batteries and you can buy them much cheaper than 9 Volts. It makes sense that 6 AA's will give you 4-5 times the life of a nine volt.
Jumper out the last two positions .

I guess this comes from my desire to get every penny's worth out of everthing I buy.

I meant no harm and stand corrected.

mshm

[Harley]

mshm99, I don't find any fault with your proposal; as long as it can't do any harm, it's a good idea and you're right to compare it with re-using plastic bags, which are an environmental hazard just like batteries.

Harley

[mshm99]

I learn something every day and a lot from this board. Thanks to all for their input.

mshm