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Old 12-07-2020, 11:14 AM
glend (Glen)
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glend is offline
 
Join Date: Jun 2013
Location: Lake Macquarie
Posts: 7,121
Quote:
Originally Posted by MarkInSpace View Post
I found this: doco says it can deliver 12V and it looks well built...
https://www.jaycar.com.au/20-000mah-...ports/p/MB3797
any thoughts?
That 20,000mah is equivalent to total 20amps, at USB voltage and amps. I doubt you could rig it to power an HEQ5, which requires 12Vs. Skywatcher says the HEQ5 needs, 11 to 15 V DC 2Amp (Tip positive).

The car starter booster battery packs are probably ok, but keep in mind they are designed to provide alot of amps for a very short period, to start a car, and typically they contain about a 17amph battery.

If you need 12V 2amph for say four hours, you need 8amps of supply. Since recommendations are to never discharge below 60% capacity that 17ah battery might not do the job for a long period of time. A 20Amph 12V battery would be a better choice. Also have a look at 12V alarm batteries, they are designed for home alarm back up, are small, and you can buy various AH capacities. Doesn't matter if they are sealed lead acid. Sealed lead acid batteries are always cheaper. Have a look at this one:

https://www.batteriesdirect.com.au/s...yABEgJgnfD_BwE

Last edited by glend; 12-07-2020 at 11:26 AM.
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