Vishal,
There have been some reports with the G11G that the higher 15V power supplies work better than 12V. The same probably applies to the GM811G. With my G11G, I use the Losmandy supplied 15V 4.3 Amp AC/DC converter:?
There probably are some less expensive converters out there but I decided to go with the manufacturer's official unit. TEC cooled cams can pulled 2 or 3 amps, and dew heaters use a few amps too. But with the total load applied you might be dropping below 12V; you would probably need to check with an inline voltmeter/ammeter to be sure.
Regards,
John??
