HitecAstro DC controller - power adapter?

[emadmoussa]

Hola,

Just received my HitechAstro DC focus controller. I knew it required a 12v DC plug, but it came with a built in 12v cigarette lighter male DC adapter - or whatever it is called. Is there an adapter out there I can use to plug this into the normal house mains?? Sorry, I don't know what it is exactly called, hence the inability to find an answer on Google.

Shouldn't it draw power through USB from the computer instead?

r

[emadmoussa]

mm..Anybody?

[SnakeyJ]

Hola,

Just received my HitechAstro DC focus controller. I knew it required a 12v DC plug, but it came with a built in 12v cigarette lighter male DC adapter - or whatever it is called. Is there an adapter out there I can use to plug this into the normal house mains?? Sorry, I don't know what it is exactly called, hence the inability to find an answer on Google.

Shouldn't it draw power through USB from the computer instead?

r

There is and I have one, but not sure where it was acquired from.

There are a few on Ebay - but you will need to confirm the power requirement for the focuser (though wouldn't imagine this would go anywhere near 1A). The plug itself should be fused to protect the focuser:

http://www.ebay.co.u...892033921&ps=54

this looks like a maplins label, but sure they or RS will also do them.

Not so critical for focuser or dew heaters, though these connectors are not the last word in reliability and can easilly be knocked/yanked out and can also be sensitive to rotation.

[Monty]

Do you mean one of these? http://www.maplin.co.uk/12v-5a-car-socket-power-supply-42702

[emadmoussa]

This is the exact AC:

[emadmoussa]

I'm just thinking, why on earth do they make it a Cigarette AC?!!!! I don't even have a car...

[Helen]

I'm just thinking, why on earth do they make it a Cigarette AC?!!!! I don't even have a car...

Most of us use portable power tanks rather than a mains supply most of the time so a cigar tip is the most useful.

Helen

[emadmoussa]

Most of us use portable power tanks rather than a mains supply most of the time so a cigar tip is the most useful.

Helen

Unfortunately, Helen, ''most'' doesn't quite apply to me. In my case, it's all a back garden obsy controlled from the kitchen..

[emadmoussa]

OK, I guess this will do for the time being. http://www.ebay.co.uk/itm/250892033921?ssPageName=STRK:MEWNX:IT&_trksid=p3984.m1439.l2649

[sparkyjon]

Unfortunately, Helen, ''most'' doesn't quite apply to me. In my case, it's all a back garden obsy controlled from the kitchen..

no offence but i couldn't think of anything more soulless , if i was doing the remote stuff i'd still have to sit out on a chair and look up , i did start doing it but realised it's a lot of stress for our countries weather,,,

not knocking it all but i thought the point was to look up and enjoy if you wanna watch it on a screen might as well just watch discovery channel and save a fortune

[sparkyjon]

OK, I guess this will do for the time being. http://www.ebay.co.u...984.m1439.l2649

be careful that the output is enough to run the device, 450mA isnt alot..you might end up frying the fuse

[emadmoussa]

no offence but i couldn't think of anything more soulless , if i was doing the remote stuff i'd still have to sit out on a chair and look up , i did start doing it but realised it's a lot of stress for our countries weather,,,

not knocking it all but i thought the point was to look up and enjoy if you wanna watch it on a screen might as well just watch discovery channel and save a fortune

Yep, I see what you mean. I keep coming out to check and look up at the sky...mostly when I'm doing AP. For visual, I'm out there freezing my head off.

The response to Helen was merely regarding electric connections.

[emadmoussa]

be careful that the output is enough to run the device, 450mA isnt alot..you might end up frying the fuse

Awesome! Just ordered it...

[sparkyjon]

it might be ok i dont think it will pull a lot it's only for a focuser isnt it?

[emadmoussa]

it might be ok i dont think it will pull a lot it's only for a focuser isnt it?

Only for the focuser. Just another addition to the pile of adapters. It surprises me they go all the way developing such interface adapters and charge a lot of pennies for them...then, nah...we can't sell it without the USB cable or a £1 AC adapter ... classic niche market syndromes...or shall I say, black market ?

[AstroTux]

It surprises me they go all the way developing such interface adapters and charge a lot of pennies for them...then, nah...we can't sell it without the USB cable or a £1 AC adapter ... classic niche market syndromes...or shall I say, black market ?

The main issue here is that the HitecAstro DC Focuser is aimed at handling almost any small motor you care to throw at it. If is mainly for use with a 12V power supply due to the voltage/current requirements of most motors used for this purpose, but can be driven at higher voltages ( and hence motor currents ) if required.

Unfortunately USB is not aimed at driving motors and has a power limit of 500mA, which is reduced to 100mA if the device is the connected to an unpowered hub. 100mA is not going to move a small DC motor very far or fast, hence the need for an external power source.

Having just 'repaired' one of these units I know that the motor drive chip is an L293D which can handle up to 600mA per channel, so I think you can see that just a USB connection would not handle this. Its not the fault of the device, it's the limitations imposed by USB that require this sort of design.

Hope this helps,

Alan

[emadmoussa]

The main issue here is that the HitecAstro DC Focuser is aimed at handling almost any small motor you care to throw at it. If is mainly for use with a 12V power supply due to the voltage/current requirements of most motors used for this purpose, but can be driven at higher voltages ( and hence motor currents ) if required.

Unfortunately USB is not aimed at driving motors and has a power limit of 500mA, which is reduced to 100mA if the device is the connected to an unpowered hub. 100mA is not going to move a small DC motor very far or fast, hence the need for an external power source.

Having just 'repaired' one of these units I know that the motor drive chip is an L293D which can handle up to 600mA per channel, so I think you can see that just a USB connection would not handle this. Its not the fault of the device, it's the limitations imposed by USB that require this sort of design.

Hope this helps,

Alan

Thanks Alan, that's useful information indeed.

My main complain was that like a lot of products in the astronomy equipment industry, producers don't seem very interested in providing a service to ''every one involved in the field''. That is to say, assuming that everybody uses a power tank, hence the cigarette adapter, is in ''Vulcan'' wording: illogical. From experience, every time I buy a similar adapter I end up buying accessories - be it another adapter for the adapter itself All that adds up.

It's understandable that ''mass production'' is not a characteristic of the astronomy niche market, which explains the lousy packaging of a lot of products. I'm assuming this will take the cost down significantly. On the other hand, USBs and 12v plugs are mass produced and thus very cheap. So having paid £69 for the Hitech Astro controller, in my mind it seems like a natural thing to include at least a 12v AC plug, or a USB cable.

[sparkyjon]

i know what your saying Imad it is frustrating, but i can see the point of view from the manufacturers also , the other issue here is electricity and outdoor pursuits like astronomy dont really mix ,,the fact is if someone had a 230v ac- 12v dc mains plug and got the plug wet from dew (cant make dew shields for plugs ) as an example , then had an electric shock off that plug top , even though it's a 12v transformer and relatively safe, they would no doubt blame the manufacturers , if they supplied I.P. rated plugs it would become expensive..so yes as you say it is a cheap cop out by them supplying a 12v cigarette adaptor, although it suits 85% of the astronomy market , there is a gap for people who do it all from a station either in doors or in an obsy..