Hi Russ,
you can do your own battery pack like this one:
www.dodotronic.com/product/power-bank-d-batteries
There are some points to consider:
- keep the battery voltage much close to the final voltage output if you
are using a switch converter
there are two tipologies of switching converter:
1 - step up (boost) switching converter - the output voltage is higher than
the input voltage (high efficiency)
2 - step down (buck) switching converter - the output voltage is lower than
the input (good efficiency)
3 - buck boost converter - the output can be up or down the input (variable
efficiency)
A different tipology of converter is the switching capacitor, this doesn't
uses an inductor but a capacitor instead. The efficiency can be very high
but the output current is quite low. The output must be much higher than
the input in order to reach the best efficiency
The main difference between the inductor and capacitor typology is that the
first one can deliver high current but with a higher noise too. a good
solution is to place an high electrolytic capacitor at the output so to
reduce the voltage ripple.
Conclusion: you can buy a chinese converter, they are usually high
efficiency IC but sometime have a bad quality
Here one I tested with good quality
https://www.amazon.it/gp/product/B07FCFP8WF/ref=3Dppx_yo_dt_b_asin_title_o0=
7_s00?ie=3DUTF8&psc=3D1
Put a 100uF at the output to reduce the ripple
And 3 D size batteries
Check it all before powering your final device
p.s. if you need a low power autonomous recorder you can take a look here:
www.dodotronic.com/product/ultramic-384k-ble
Ivano
Il giorno lun 22 lug 2019 alle ore 17:34 Russ Wigh
[naturerecordists] <> ha scritto:
>
>
> Hello all
> I am trying to calculate what I need to do screech-owl surveys this fall.
> The equipment would usually be left overnight at dusk and picked up early
> the next morning. Since the recorders will be running at night, powering
> with solar is out, of course. For one of three units, the 722 with a
> NP-F970 Sony lithium battery, I will set the internal recording timer and
> there will be no need for external power since it will run most of the
> night anyway.
>
> The other two recorders are an Olympus LS-10 (expropriated back from my
> granddaughter) and a Zoom Hn4. I envisioned small lead acid batteries
> connected to pure sine inverters, and Intermatic timers to shut the
> recorders down. But all the reviews I have read on Amazon and B&H have
> enough negatives to convince me that these Chinese-made products are a
> crapshoot. Clearly I do not want to spend an arm and a leg on this stuff,
> since it is not likely to have much future use. To wit, if anyone has som=
e
> knowledge, experience or even a considered opinion for a solution, I woul=
d
> much appreciate it.
>
> Russ Wigh
> Skidaway Island, Georgia.
>
>
>
--
www.dodotronic.com
|