powersource?

[GazzMeister]

Hello All

I will be getting an EQ6 very soon and was wondering if anyone had any ideas for powering it? I'd prefer something that will work "out-of-the-box" rather than a car battery that i'll have to modify. I can use mains power at home but if I go out to a dark sky site i'll need something portable. How do the celestron powertanks go? Are there any better alternatives? any help will be much appreciated.

Gareth

[wavelandscott]

I am not a big user of portable power...I only need an occassional bit of juice to power my dew heater. For this I use a jump starter power pack that I got from Super Cheap Auto...It has a cigerette lighter plug that I can power my dew heater from. Works fine for me and from memory was much less expensive than the Celestron power tank...I've had mine for two years...so far so good.

I am sure that people that power mounts etc. will have more helpful comments to make.

[peter_4059]

I have a Supercheap jump starter that works fine (600amp superforce variety). For home use where I have 240V I use a 12V 3amp regulated power supply (Dick Smith) that saves recharging the jump starter all the time.

[MrB]

Those starters have a SLA sealed-lead-acid battery in them, usually around 7Ah to 12Ah size.
For field power, places like Altronics and Jaycar have the same SLA batteries(not starter) pretty cheap.
If you go for one of these, never discharge the battery below 11v(10.5v worst case) and be sure to get a decent SLA charger for them, it can make a huge difference to the life of the battery. Charge them often, Lead-acids don't like to sit idle for more than a couple of weeks.
Miss-treated Lead-acid's have a life measured in months, well-treated they can last upwards of 10 years.

Altronics (http://www.altronics.com.au/index.asp?area=prod&grp=198)
Jaycar (https://secure.vividcluster.crox.net.au/jaycar2005/productResults.asp?whichpage=1&pagesize=10&keywords=&CATID=18&SUBCATID=250&form=CAT&ProdCodeOnly=&SPECIAL=&Keyword1=&Keyword2=&pageNumber=&priceMin=&priceMax=)
Compare prices as they do vary.

[rapidfire]

Yup, I just got one of those jump starter packs as well. 17AH's of power. nice and cheap and easy. Plus its original purpose is quite handy too. I got the one with built in compressor so now i wont pass out blowing up airbeds when camping :P

[madwayne]

Another vote in the positive here for Super Cheaps jump starter battery packs. I have two a 17AH and a 24AH. The 24AH has a warning indicator once you get low on power which I have found to be very handy, it kicks in at 11V from memory and has only come on once. The 17AH powers my LX90 all night without any dramas and I use the 24AH for my laptop because it is a V8 when it comes to battery power.

You should be able to pick up a 24AH for around the $130 mark (17AH was under $100 6 months ago), I was lucky with the 24AH it was 20% off when I bought it.

Good luck with your choice, as you can see there are plenty of options.

Clear skies.

[GazzMeister]

Thanks for the info guys. Looks like I'll be taking a trip to supercheap to check things out. Thanks again.

[Kokatha man]

Supercheap have them over here in SA at just over $80 for the 17aH unit but I went nextdoor to Sprint Auto parts (I think they're another national chain) and got the same inut for just over $70.Thing was Sprint only had black colour.....

They all come with chargers - 240V ac and 12V dc (cigarette lighter plug) the latter doubling as the 12V dc power take-off. Great for the HEQ5 Go To.

SLA batteries don't have "special" chargers - it's just that for most purposes they are (relatively) small capacity lead-acid batteries, and demand a lower in general charge rate with a lower output voltage; to ensure at "cut-off" a lower (than average) "trickle" charge continues to pump the fully-charged battery, though it's preferable and much more beneficial to their life to switch off when fully-charged.

Regards, Darryl.

[jjjnettie]

I just ordered one of these.
http://www.dealsdirect.com.au/p/power-station-air-compressor-portable-rechargeable/
And one of these.
http://www.dealsdirect.com.au/p/lenoxx-power-inverter-car-ac-usb-power-source/

[iceman]

Interesting, Jeanette! Let me know how it performs.

[Kokatha man]

Hi Jeanette - I don't want to sound like the harbinger of doom and gloom but maybe you should make a few enquiries before they take your money.

As in my last post on this subject, Supercheap Autos sell these types of units starting from just over $50, including ones with inflaters. Reading the ad links you've supplied, my first reaction was to the customer review of "Antionette" (sic) who claimed she used the unit twice before it packed up!!! Secondly, the bits about "do not use on larger power batteries (1000W)" and "do not use on batteries that exceed the power invert power."

Neither of these 2 statements in themselves have any basis of technical sense, though I appreciate what they may be referring to. As for the inverter, though it is a modest output unit, even coupling a device that uses 50-60 watts of power will need a constant current of 6-7amps (taking efficiency into account) over the intended usage time . This little unit is extremely unlikely to be able to supply aforesaid current for any length of time at all - they are designed to deliver a high current output for a few short "bursts" such as is required to jumpstart car batteries that have failed for whatever reason.

As stated, I don't want to sound depressive, but these are the facts when assessing the suitability of such equipment. My best regards, Darryl.

[Kokatha man]

Now I'm becoming really depressive! If you read into all the customer reviews (not just "Antionette" sic)and note what people are really saying and how they use the unit you'll ring them up and cancel your order!

Cheers, Darryl.

[Glenhuon]

I had occasion to repair a similar unit for a friend a while back and wasn't too impressed with it.
The inverter might be the way to go, but with some large SLA batteries.
Reading this thread reminded me a friend found this unit in a tip a while back (He's a tip scavenger extraordinary :) ) and I've just given it a check out. Didn't appear to work at first but it seems to need a resistive load to crank it up. A small lightbulb is enough.
Anyone seen these before ? Wondering if it would run the laptop without doing damage.

Cheers
Bill

[Kokatha man]

You'd really need to check it out Bill - looks like (with it's aluminium case/chassis) a vintage one from 20 plus years back: I think this company is now defunct.

Obviously a 400 watt unit; though whether it was a square wave or sine wave output device you'd have to ascertain - anyone you know with a CRO? If you've a friendly TV repair mate he'd sort that question out. Frequency control/stability is another ponderable, fixed 50Hz inverters would've used a crystal oscillator to "lock" this frequency.

As to its suitability for your laptop, many/most actually convert the 240 VAC back to DC to use on their "rails" (read circuitry power feeds) so they are ammenable to square wave unfixed frequency inverter outputs. Square wave jobs, however, can throw out a lot of radio interference - but in reality laptops usually have an adaptor that converts everything to 12-15 volts DC. Which is to say that you are far better of dispensing with the inverter (because you are just wasting energy) and run it off of a stable DC source: batteries being one such source!

Regards, Darryl.

[Glenhuon]

Was just a thought. Your right, I have 2 12x33AH Gell cells and the laptop needs 20v, so probably a simple LM317T voltage regulator circuit would be easier on the power drain (and a bit lighter to lug around than the inverter :lol:)

Cheers
Bill

[h0ughy]

I have 2 110 Ah deep cycle batteries and two 24Ah supercheep jumpstarters - thats runs my cooled camera - the mount, and a couple of heat straps for a night

[Zuts]

I have the previous version of the supercheap jump-starter. It wasnt 50 bucks but i think i paid about 100. Anyway, its 24 amp/hours and it runs my EQ6, dew heater for my TV 85, laptop for guiding off a cigarette plug converter (not inverter) for a full nights imaging, longest has been 8 hours.

It also jumpstarts my car :)

Regards Paul

[Kokatha man]

Exactly fellas - the $50 - $60 ones I was referring to Paul, were the one's with the lowest capacity (battery amp-hours) and your 24Ah unit is one of the heavier duty jobs: they start at approx 10-12Ah (mine is a 17Ah which is fine for the HEQ5 SynScan) and go up to your version and beyond.

One of the points I was making to Jeanette is that hers would have been (based on price but also from the abysmal "customer reviews") on of the lowest capacity types and not worth purchasing if you have intentions of running anything except maybe one of the small Nexstar goto scopes etc. What I found amusing/insulting was that the "customer reviews" were very unflattering but it didn't seem to deter the company from putting 4 or more stars as its rating of each! (except from "Ben of Springvale.")

Cheers, Darryl.