What bulb for 8.4 volts?

Pi_is_blue

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I just got my DMM, so I decided to measure the voltage of 3 fresh NiMH batteries in a 3toD adapter. Came out at about 4.2 volts. So what is the best bulb to run at 8.4 volts or less? I want to turn my old 2D gaglite into something bright. /ubbthreads/images/graemlins/grin.gif
 

shiftd

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Pi, i think you cannot get high current to run high V bulb using the 3 to D (recall: the high resistance in the holder), but i dunno if that has changed. Anyway, if you really have 8.4 V, i think any of the 5 cells bulb will work.
 

PaulW

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I would think that just about any bulb that works with 3x123 would work with the 6xAA in the 3toD . . . provided you do the 3toD mod. A lot of them will work even without the mod, if the current is not too high. I believe that the KPR-112 and Shiftd's suggestion, a 5-cell, ought to do pretty well with the stock 3toDs.

Paul
 

shiftd

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ditto what PaulW said.
it may works, but the result might not as GREAT as with perfect holder /ubbthreads/images/graemlins/grin.gif
 

Rebus

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I'm running the same setup and
I am getting the same voltage.
Mine works well with the Kpr112.
When the voltage goes down to
about 7.3 volts you can switch
to a Kpr113. This is working well
with my unmodded 3toD holders.
Not bad for a total of about a
$25.00 investment.
Someone needs to do a real runtime
test on this setup. I think it will
go longer than some of the quesses I
have heard (half an hour).

-Rebus
 

PaulW

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Rebus,

The KPR-112 draws about 800 mA. That should give it a run time of about 90 minutes.

Paul
 

snakebite

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6 ni** cells are rated at 7.2v
open circut fresh off the charger can be 8.4+.
this is surface charge that is lost when you load them.
 
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