Power expert needed?

[Smudgeypoo]

I have been rooting through various ac/dc adaptors that I have in the shed but have been unable to find one between 11-15v dc output.

I have found 1 that is 9.5v 1.5amps and I'm guessing thats not enough to power a Synscan AZ goto mount but would not do any harm trying??

I also have 1 that is 17v 3 amps, trying this may cause harm I think but voltage could be reduced by fitting a resistor inline?

Any advice is greatly appreciated as to whether either of the supplies mentioned above could be used. I will get the one from Maplins which is on offer at the mo for £9.99 when I get chance anyway.

Thanks v much.

[umadog]

Don't worry about the amperage rating, that's just the maximum power output of the adaptor and the appliance will take only what it needs. Remember that a car battery (better yet a marine battery) can power a telescope quite happily and those things can push out major big currents.

[ScubaMike]

I personally wouldn't risk burning out the mount with too high a voltage.

The 9.5v is probably too low to power the mount.

At £10.00 it seems a logical choice to me.......

[Cornelius Varley]

I have been rooting through various ac/dc adaptors that I have in the shed but have been unable to find one between 11-15v dc output.

I have found 1 that is 9.5v 1.5amps and I'm guessing thats not enough to power a Synscan AZ goto mount but would not do any harm trying??

I also have 1 that is 17v 3 amps, trying this may cause harm I think but voltage could be reduced by fitting a resistor inline?

Any advice is greatly appreciated as to whether either of the supplies mentioned above could be used. I will get the one from Maplins which is on offer at the mo for £9.99 when I get chance anyway.

Thanks v much.

Using an adaptor with a low voltage output is almost as bad a using one with too high an output. The low voltage will cause the handset to perform irratically and the higher voltage might blow the electronics. Make sure the maplins PSU also has a regulated output. The cheaper non regulated PSUs are not regulated and can also cause problems. If the Maplins PSU is this one Low Cost 6W Multi-Voltage Power Supply : Multi Voltage Power Supplies : Maplin Electronics, don't buy it. The output is unregulated and is unsuitable for powering your mount.

Peter

[Smudgeypoo]

Thanks for the replies, guess I'll leave the DIY route alone then......though I do have a 12v 35ahc motorcycle battery in the shed.

Cheers

[x6gas]

Thanks for the replies, guess I'll leave the DIY route alone then......though I do have a 12v 35ahc motorcycle battery in the shed.

Cheers

Yep, better off using that and I agree with Peter that if you want to move to AC power later on buy a decent regulate power supply. I have a 10 A job from Maplins which I run through a home-made distribution box to power my mount, dew shield, cameras and filter wheel.

Oh, and if you do go down the AC route make sure the power supply is protected by an RCD.

Cheers, Ian

[Kerrp30]

Do not use a resistor in line to reduce the voltage as you will need a high wattage rating of resistor as the volts drop x the current gives you the wattage you will need.

I use a 12V car battery emergency pack from halfords and it powers a Celestron CPC800 mount. This works everytime without fail. Plus you cannot get more than 12V from the battery.

Paul

[pete_l]

Any advice is greatly appreciated as to whether either of the supplies mentioned above could be used. I will get the one from Maplins which is on offer at the mo for £9.99 when I get chance anyway.

Apart from the voltage and current capabilities of the power supply you're going to buy, make sure that the plug is the right size.

Seriously, there are many, many different power supply plug/socket combinations and some are very nearly (but not quite ) the same size - but different enough to either be a loose fit that drops out and reboots your 'scope - or is a force fit that stresses the connection on the scope's circuit board. A lot of PSUs come with a selection of various sized connectors. If you have the choice, get one with lots of different sizes, not just one that looks like it's about right.