My dew heaters did not keep the dew off the scopes, last night. I had them plugged into my hub. i unplugged them from that, when I realised I had a problem, and powered them from a car battery. had another look & the 120 had dew all over it again, and the underneath of the strips were wet.
I tested all the strips today via car battery & they were sort of a bit warm. I had them on full. I often think they are not working as they are so subtle i dont know how they are working.
has anyone any info on their strips & do mine sound right, also on a very heavy dew night, would they have trouble coping. i wrap them around the area where the lens is.
Thanks
Dew strips deliberately have a fairly subtle effect but they ought to keep dew off the objective lens as long as they are wrapped around the scope at the location of the lens itself.
The only problem I've experienced was when one "broke" part way along the length meaning that most of the length remained cold.
mark
i will have a look at that Mark, what heat there is, does not go along the full length. once it gets cold the wires are so brittle
The strips should feel slightly warm the objective is to be a couple of degrees warmer than the surrounding temp. The best way to test the strips is with a voltmeter, set it to DC and place it on the bare wires (try unscrewing the phono plug), depending on where you sent the power you should see voltage oscillate between 0 -12v the delay will decrease the closer you are to max.
i am not too technical Ivor but will try.
what make dew strips do people buy, i am wondering if mine are inferior. I got them from Bern
Fay,
I can lend you a Chirs Suddell Patent Telescope cooker. My home made dew heaters can cook and egg (6amps into an ED80), I know I tried it. Bit sad I know, but when its cloudy always good to have a 2nd use for the kit!
Chris
Sorry I made mine as well, it gave me an excuse to dust of my soldering iron. I'm not sure mine would cook an egg alas my scope is only 110mm so a lot less resistors.
Weather permitting I'll be coming to DSC on Saturday so I can bring my voltmeter along and we can have a look.
Speak to Duncan. He sells dew heater kits remember.
well you know how quick off the mark i am, i have ordered a Kendrick, to see if it is an improvement
Thanks Ivor, weather permitting
Quote from: Rocket Pooch
My home made dew heaters can cook and egg (6amps into an ED80), I know I tried it.
6 amps x 12 volts. That's 72 watts. Yep you can slow cook an egg on that.
I once saw a TV program where they roasted a chicken using a 100w light bulb. Seriously! The "oven" was a very well insulated box just a bit larger than the chicken and light bulb. It took only a few hours to cook and I seem to remember the power came from a man on a bicycle spinning a generator. When you consider the average domestic electric oven is 4-5 kW, it just goes to show how incredibly wasteful they are.
When the next almighty solar storm fries all electrics worldwide, we'll probably have to resort to bicycle generators to do our imaging. You'll be able to image for as long as you can cycle. It's a good reason for keeping your kit running off a car battery.
That reminds me - I've forgotten to put my backup hard drive and my spare laptop (runs off a car battery) back into their tin foil lined box.
Mark
we'd better all get our legs in good shape then...................
Mark do you also wear a pointy hat made of tin foil when imaging?
Who`s been watching "Signs", then ..... :D
Quote from: doug
Who`s been watching "Signs", then ..... :D
What is "Signs"?
A film starring Mel Gibson and Joachim Phoenix about supposed aliens on the roof of his house ..... :suspicious:
Quite amusing!
Doug.