C11 SCT dew heater

[Vince1963]

Hi Guy's.. Just want to pick the brains of some of you tech guy's on here, I just bought a Celestron C11 SCT and i just know i'm going to need a dew heater and maybe a controller too (Do i need a controller ), But at 75 quid i think i'll make one. Now the thing is i don't have a clue as to how lol..... Having said that i'm sure its not beyond my capabilities, As long as i have some plans to follow on making one, I do have a soldering iron (for small circuit board work) and i can and have used it.

Does any one on here have plans for a dew heater that would suit a C11?, You see my problem is i don't know how to calculate the resistors i need for a 11" tube with the appropriate power output, I have read somewhere that you need around 2 watts and I have heard that the best place on a SCT is the boss in front off the corrector plate..

Or if anyone on here as one that would be suitable for a C11 for sale then contact me ... If you have a PDF plan for a dew heater / controller then you can email me... Thanks Guy's and clear skies

[Bizibilder]

I think you will find Google is your friend here - try searching "Telescope dew heater design" and there are several, most use a chain of parallel wired resistors and are quite easy to make. Also the DIY section on SGL has a few designs.

[Vince1963]

Thanks for that Roger.. I shall take a look