. i am wondering what other people use to power the mounts,cameras etc when out on the field. i do use a jump stater pack but i find is not enough to keep me going all night.
les
What are you trying to power? If your jump starter pack is more than a few years old it might benefit from a fresh new battery as they seem to crap out after a few, especially if left idle for a long time.
I use 2x12ah gel cels to power my argo and dew straps and never look like draining the batteries.
Up until SPSP, when my big battery died, I used a 90 amp hour for my laptop and a 40 amp hour battery for everything else, dew heater, mount and cameras. It would last me all night long in that configuration although the smaller battery would be fairly hungry for a recharge at the end of an all nighter particularly in Winter.
Now the 90 amp hour has passed on to a better place, I now use 2x 70 amp hour in it's place. One dedicated to the laptop and the other dedicated to dew heaters and cameras.
I haven't had the chance to test the new power setup since SPSP as I have not been out a single night due to Sydney's very inclement weather.
You will need to fork out and get a deep cycle battery - something like an AGM (absorbed glass matting) battery. I picked up a 45 Ah one from 4x4 place last year for $155 - normally about $200. The car-starting type batteries are really just meant to deliver a shed-load of current in a very short time, then sit quietly being charged by an alternator until the next time you start your car. THey are not meant to be discharged to any great degree repeatedly as will happen with an all nighter at the scope.
Even 45Ah may be too small if you want your laptop to go all night.
Generally you really only want to discharge these to about 40-50%, and your laptop will draw a couple of amps, plus the rest of your gear, though the mount is fairly minimal.
Les, how close to 240V are you at home? I've been surprised at how close power is generally at Astrofest, Ron's, Peter's. I like to be portable, but a good battery is so expensive you might be better off investing in a decent power supply set up first?
(probably completely off topic given the title of the thread, but hey, thought I'd throw it out there.... )
Failing that, you need to look up how many amps the QHY8 and laptop are pulling and figure out max time you would want to run and calculate some amp hour figures. Just quickly:
If you say 3amps total, and want to run max 7hrs, and never take battery below 33% charge, that would be about a 33-40Ah deep cycle battery I'd suggest. I'd be surprised if the jumpstart pack is more than 17Ah total - and its debatable how well and how many times it would be able to do that anyway. It would be fine for just the EQ6, but pushing it to run just the camera OR laptop for any period.
Agreed the laptop will kill your battery fastest - are you using an inverter to power the 240V power adaptor that comes with your laptop, or have you shelled out for a 12V power adaptor for the plugpack. The latter will probably improve your efficiency somewhat.
If I'm off 240V I have a 100amp/hr for the laptop and 30amp/hr for the mount, etc - fortunately this doesn't happen often.
I gave up on batteries years ago far too expensive and unreliable. I now use a portable generator (2KVA) of the quiet type ($600), electric/remote start/stop. I use a sound proof box as well. On my normal load of caravan, five computers, telescope/mount and camera I get 12 hrs from 5 litres.
The residual noise should not worry anyone on a cold night If you have head cover. I can't hear the generator past 10 metres and set it up at the end of a 25 metre extension cord.
During the SPSP I ran the "house" and whole area from the generator using less than 1 litre of fuel/hr and supplied everyone with AC via a 12 way distribution box.
Batteries are a pain, expensive, large and too heavy. Like Barry I use a small genset (honda Eu10i) which has 1kv capacity clean power (excellent for laptops, garanteed better than mains) and will run for 8 hours on 2L of unleaded. Quiet as a mouse (52dB) and as light as a feather (~15kg wet). Best thing is it is about the size of a shoe box so takes up little space. It even has a special circuit to charge 12V batteries built in. A much better option then deep cycle batteries by a fair margin. Runs my mount, CCD's, laptop etc etc at idle. Details here.
I'm well prepared.
My son and My grandson as well as me and I have one hooked up just for TV as well as two lap tops.
Mark has the right idea. Those little Hondas are great. I got a cheap generator off ebay 2.5 KVA but only half the price of the little Honda and I needed a bit more power. It is a little noisier 59db but the sound deadening fixes that.
its a little unpractical for me to run and extension lead to the nearest power source 500m away. i had thought of generators as my view on them would be too noisy so i wasn’t to sure on that
thanks for some ideas,
les
its a little unpractical for me to run and extension lead to the nearest power source 500m away. i had thought of generators as my view on them would be too noisy so i wasn’t to sure on that
thanks for some ideas,
les
Les the Honda genies are so quiet you can have a normal conversation standing right next to it. There is no need to move it off into the distance or make a shield to cover it and no need to shout to be heard when near the machine. For AP they are ideal and rarely move above idle even when the mount is slewing at max rate with the peltier and dew heaters going flatout whilst the laptop is operating in flatten the batteries in 5 min mode. Love it as it is just so convienient. When I priced deep cycle batteries to do the same job it was huge and cost about $750.00 here. The generator just made a whole lot more sense.
I find those generators attractive, too, but don't they cost twice as much? And a lot more to run as well (fuel, oil, maintenance)?
Cheers
Steffen.
Steffen I got mine for $1300.00 so yes it was 2 x as much as the deep cycle battery but came with a 5 year warranty (not so with the batteries). The cost to run (fuel) is $2.00 for 8 hours. How much does it cost to charge a deep cycle battery 4X (would only get 2 Hr's by my power requirements). So for fuel the grand cost is 25c per hour. From the manual the engine oil gets changed every 100 hours of use (250mL), the spark plug, and air filter is replaced every 300 hrs. Valve clearances and fuel filter every 2 years. In short 2 halves of bugger all to run. Advantages over the battery setup are
1. It doesn't go flat.
2. Runs all night providing lots 240V power (boil the kettle, run the microwave, mount, camera's laptop etc).
3. Takes 10 seconds to refuel and you are away again.
4. Is very light and small so easy to handle.
5. Can be used for dozens of other applications (power tools etc).
6. Can be linked with another genset of same type to boost output to 2kV.
6. Can be used to charge flat 12V batteries of other astro folk .
7. Makes less noise then my LX200 in a slew (Okay so the battery is quieter) .
8. It's a honda so it is reliable and does exactly what it is supposed to do with no hassle.
For me points 1, 2, 3, 4, 5, 7 and especially 8 were the major selling points. I have used Honda gear in many hard industrial applications and they are virtually bullet proof (nb: I also drive honda cars but do ride Ducati's). Sure there are other cheaper options for genies but be careful about quality and make sure it is rated to power computers etc or you will end up in trouble. For me it was a no brainer in the end, the battery option was not even in the hunt as I would need 4 of them to do the job of 1 generator.
1. It doesn't go flat.
2. Runs all night providing lots of power (boil the kettle, run the microwave etc).
3. Takes 10 seconds to refuel and you are away again.
4. Is very light and small so easy to handle.
5. Can be used for dozens of applications (power tools etc).
6. Can be linked with another genset of same type to boost output to 2kV.
6. Can be used to charge flat 12V batteries of other astro folk .
7. Makes less noise then my LX200 in a slew (Okay so the battery is quieter)
Oh, I agree with all these advantages. I just think it is a very expensive luxury.
Regarding battery recharge costs, I'm paying about $0.18 per kWh, and 1kWh gives a hell of a lot of recharges. But running cost isn't nearly as much a concern as purchase price.
If I was more into camping a generator would probably make more sense. As it is I just need to help one laptop through the night, and for that I reckon a $100-200 AGM battery plus $50 charger are a better choice.
Any recommendations on chargers for AGMs folks? I don't really want to spend over $100 for one if I can help it, but expect to get max battery life you get what you pay for?
. i am wondering 
what other people use to power the mounts,cameras etc when out on the field
. i do use a jump stater pack but i find is not enough to keep me going all night.
)
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