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Posts Made By: David Simons

June 12, 2007 08:10 AM Forum: Equipment Talk

Best choice of filter for viewing NAN ?

Posted By David Simons

Hi John,

Last weekend I had pretty good luck with an O3. I was at about 2.5 degree FOV. Although I have heard a UHC might be better.

July 12, 2007 11:54 PM Forum: Refractors

What refractor do you bring to a star party?

Posted By David Simons

>>
I was wondering what refractors (not including finder scopes) others bring to a star party.
<<

Hi Bill,

I hope to bring my 8" f6 refractor (still in progress) to the Oregon Star Party.

August 7, 2007 03:06 PM Forum: Refractors

Re: Refractory history question

Posted By David Simons

Hi Greg,

Sorry, I was getting Herschel and Ross criss-crossed.

Herschel only had a 48" scope !

Greg Nowell said:

Here's a picture of Lord Rosse's secondary mirrors. (I was at Birr Castle last week). So when his mirrors were fresh he was at roughly 50% light throughput, but apparently this would rapidly degrade to 16%. regards Greg N

August 15, 2007 05:51 PM Forum: Refractors

C102F - Restored

Posted By David Simons

Paul said:

<<< ... ended up with a couple of these blacktubed Celestron C102F's .. >>>

A couple ?

BTW, awesome restoration. My black C102F is in pretty bad shape also. Nice to see what the options are, thanks for your inspiration ! grin

August 16, 2007 07:23 PM Forum: Equipment Talk

DD-1 is hot!

Posted By David Simons

Hi Alan,

Your story sounded familiar, I did a bit of searching on the fourms for "DD-1", and basically found the voltage for the DD-1 has to be no more than 12V as it has a linear regulator inside the unit that drops the voltage to something much lower. The specs for the controller were on the "Company 7" website:

[COLOR="Blue"]Power Input: 7.5 to 12 Volt D.C.
Current Draw: 800 milliamps (maximum)
[/COLOR]

So if you Radio Shack adapter is putting out the usual 13V, it would stress the DD-1 regulator too hard. Some of the solutions I saw in other forums talked about dropping the voltage to around 10V using high current dropping diodes. Maybe just using 7 batteries might help. For the eighth battery location, you can use insulating tape to cover a battery's terminals, then wire around it with some 20AWG wire. Other solutions I saw were to get tighter regulated power supplies. But the DD-1 controller will still get very warm, as all linear regulators will unless they have good heatsinking.

Alan Strauss said:

Good evening-

I am curious as to how much heat is typically generated by a Vixen DD-1 controller? I recently acquired one and also purchased an AC adapter from Radio Shack...when powered on, the back of the hand controller seems to get rather hot. Not warm, but hot. I also tried using it with the 8-D cel battery pack and it still heats up quite a bit. Everything functions fine, but I am worried that so much heat can not be good for the electronics. Opinions? (I am clueless about electronics :S )

Thanks-

November 11, 2007 09:32 PM Forum: Solar System Observing

Comet 17P/Holmes is undergoing a spectacular erupt

Posted By David Simons

Finally had some reasonably dark clear skies up here in N. California, and I brought out my 25X power 3 degree FOV 125mm Vixen binoculars.

As I was searching around the bright stars of Perseus, suddenly this massive globe of fuzzy light swung into the FOV. I know the stereo effect is not real when looking at Astronomical objects, but the comet was so obviously in front of the stars, and the whole image simply looked like a giant ball, it took me by surprise. This was a real OMG moment. The effect of one side of the comet being sharp, and the other fuzzy with just a hint of tail in the nucleus made the comet look like it's aimed toward us!

Highly recommended for binocular fans !


November 12, 2007 08:38 PM Forum: Telescope Making

How did I live without this ? (Bandsaw)

Posted By David Simons

This was a piece of cake ! I love it grin

November 12, 2007 10:26 PM Forum: Equipment Talk

Dall-Kirkham vs a SCT

Posted By David Simons

Here is a brief comparison between an SCT225 and the Mewlon 250

http://www.cloudynights.com/item.php?item_id=543

I have never looked through a Mewlon 250, but can say the SCT225 is about everything a 9" SCT could hope to be ! grin

The picture is from a side by side of a Celestron 9.25" and the SCT225.

November 21, 2007 04:35 PM Forum: Equipment Talk

Rebuilding a battery pack

Posted By David Simons

Here is a link to Dave Bonandrini's article:

http://www.astromart.com/articles/article.asp?article_id=587


Ken Landaiche said:

Do any of you have experience rebuilding a rechargeable battery pack? I remember reading about testing the cells and replacing bad ones. But I can't find the post here anymore. Many thanks for any leads to the recipe.

November 28, 2007 02:01 PM Forum: Telescope Making

12" Hastings aluminum tube - Very Nice!

Posted By David Simons

HI Mike,

My last tube from Hastings was a 10", 6ft, 0.064" wall. It was physically in great shape with a very good circular profile. The seam was visible, but very smooth and should finish nicely. I was thinking of polishing, then a clear coat finish. It will go with my 8" f10 achromat.

Mine was quite oily though, and I had to give it a bath. :S