Hi Chris,
Appreciate the time and effort to share your knowledge and experience.
Its been a steep learning curve for me personally getting into astronomy. I have never been good with electrics and this is a totally unknown for me, hence the multiple jumpstart packs
I will look at car batteries as i never thought about using them to power a scope. I assume i needed a particular type.
Thanks again to all for sharing
Regards,
Mel
Quote:
Originally Posted by Nebulous
I guess it depends on what you're trying to drive but, like Raymo, I have found that old car batteries can do fine.
I'm only powering a Star Discovery mount but it seems pretty flexible. In that case, the default power is 12v from a small caddy in the body of the mount which holds 8x1.5v AA batteries. (The big trap would be trying to use rechargeable AA batteries which, despite looking exactly like the regular AAs, are actually only rated at 1.2 each. so 8x1.2 is only 9.6v , and 10 won't fit in the caddy).
I bought a lead at Jaycar to get the right end to plug in, and the young guy there tried to tell me that I needed to buy a more expensive setup that regulated the voltage. However, being also reluctant to lash out unnecessary cash I stuck with the basic $5 one!
Just out of interest, I put the multimeter across a caddy of 8 new Duracell batteries when I first got the mount and they showed over 13 volts. They were still working at under 11v. So it seems that the motors will work at quite a range. I guess they just get slower.
I also checked with Skywatcher Australia tech dept and they confirmed that the power brick that I have left over from an old modem will work fine too (it has the correct positive centre tip, 12v, and enough amperage) and that setup works fine too.
As that_guy said, it's worth keeping your batteries on trickle maintenance charge, but my guess is that you can probably use a pretty wide range of batteries and that fancy expensive ones may not be strictly necessary. I have a couple of old ones that have been pensioned off from car duties and that still hold good charge so I could swap over if that was ever required.
Good luck with it all.
Cheers,
Chris
|