Well after reading all the treads on measuring the temp of your mirror rate of cooling I thought I would build a unit to read the temps of the mirror,tube and ambient air.
Here is the unit finished and ready to be mounted to the 12".
I might have to consign you to make me one of those!!
Look forward to seeing your results! Can you make one that interfaces to a computer via serial port?
This unit does three things interfaces to the pc, displays on a LCD at the scope and saves the readings to its internal memory for later download.
At the moment I haven't got the LCD so when it does I will post the image.
Are these basically thermistors? top idea, necessity is definitely the mother of invention. Looks like stuff one could get from DSE or Tandy.
The sensors are made by dallas semi conductors I owe the idear to BIRD as it was his post that gave me the idear to use the hardware I did. See his post here http://www.iceinspace.com.au/forum/s...ead.php?t=5276.
I too am impressed. You could probably get a nice little sideline going here - custom temperature sensing gear for scopes!
This would probably be very handy for astrophotographers, since they could keep an eye on what is happening & how it affects their results. Also useful for accurately recording conditions that affect 'seeing' etc.
Here is the parts list for this unit for those that would like to build it.
I also have the code for the pixaxe unit written so if anyone does build it I am happy to supply the code, the code will be an on going process of improving it to do other features as well ie: display the current time on the screen and read humidity.
All later versions of the code will be email out to those that have already got it in their units.
Last edited by Wombat_In_Space; 06-12-2005 at 02:40 PM.
Reason: New parts list with a second option for those that dont want to store the reading in the device.
This would a *great* project to add to the Projects, Articles & DYI section (hint hint!) once you've tested it all out & tweaked it etc. I'm sure that there would be a lot of interest....
P.S. I'd be happy to get a copy of the code - I need a project to keep me busy...
It's 11:30pm and just bought the scope outside temps to start with Ambient Temp:17.62 Tube temp:19.62 Mirror temp:21.44. I have the fan running and the scope is at 45 deg angle.
12:05pm Ambient: 13.31 Tube: 14.50 Mirror: 15.44
Last edited by Wombat_In_Space; 06-12-2005 at 12:07 AM.
Reason: updating temps
If we only really care about the differential between mirror temp and ambient temp, a simple bridge circuit with a small meter or an single op amp could do the trick.
for some good weather to run some test. Here are the photos of the finished and mounted to the scope.
