Junkbox Telescope Gallery

[jeff_duntemann]

Some years back I posted Jeff Duntemann's Homebrew Radio Gallery, and for reasons unclear it's become one of the most popular pages on my site. (Tube construction may not be quite dead...) So a while back I wrote up and (almost) finished a page about all the various telescopes I've built

Comments

[johnridley]

I've owned pretty much nothing but dobsonians (other than a small grab-n-go scope, and one Schmidt-cass 8" which was OK but too small). I have a 15" and live where there's light pollution. I'd hate to try to haul a 15" equatorial scope to a site 20 miles away in my minivan

[jeff_duntemann]

You're a better (and probably younger, and almost certainly stronger) man than I. I worked with Rich Fagin (not sure if you know him) on a 16" scope years ago, and it was getting so huge and heavy that I let him buy my half of the project

[johnridley]

If a dob is wobbly, it's just badly built and no two ways about it. One of the primary reasons people build dobs is that they're so much more solid than eq mounts. It's completely beyond any sense that something that is essentially a plywood box with a center of gravity 2 feet off the ground wouldn't be more stable than something much heavier with a CG several feet higher balanced on a pipe

Re: soldering up your own Altair

[baron_waste]

If I may cut in, I have to agree with the point you made. It's true, people don't do the kind of Heathkit hobbycrafting you describe. Mr Duntemann has mentioned writing hex code by hand; nowadays hex editors are commonplace. I once worked out the orbital dynamics of a fictional gas giant and its moons using paper, pencil, time and a TI-30 - nowadays there are applets online that will calculate orbits.

The point is that soldering components by hand, hex code by hand and pages of scribbled notes and numbers are primitive arrangements. No, “new and improved” are not always synonyms - but once upon a time, operating an automobile was so complex a task that a chauffeur was necessary, possessing the same idiosyncratic knowledge of the motorcar as a livery hostler knows of horses. Today your teenage daughter hops in, starts it up and drives off without a thought. (Some people never even open the hood.So, your backyard hobbyist of today does not grind his own mirrors. What the heck, he never smelted the glass either. Where you do have

[baron_waste]

Speaking of old pictures and gadgets…

http://i28.tinypic.com/2qtct9y.jpg

Mr Duntemann, what are these two standing in front of? I thought it was a heliograph, at first glance; shows where my mind is.

I think it's a microwave receiver. Am I all wet?

[jeff_duntemann]

That's an odd one; I'm not sure women who look like that overlap with the timeline of microwave communications. There's another possibility: A parabolic microphone. There's not enough resolution to get a good look at the device itself, though my imagination wants to think that the coax connector is a Neill connector, which is good up to the low microwaves. The only remaining possibility is that this was some sort of Hollywood shoot from the 1950s, trying to emulate the 1930s. I don't think microwave gear using parabolic reflectors existed prior to WWII, though I'll have to dig in the stacks to check fersure.

Now. Wherethehell did that photo come from?

[baron_waste]

Uh, well, here, actually.

[baron_waste]

D' ye know, you're probably right about it being a parabolic mike. A serious parabolic mike. With today's equipment, that hombre could pick up a conversation out to the horizon - from a mountaintop.

Or, in this case, pick out dialogue spoken on a beach with wind and surf. I mean, these are movie stars, out on location; what else could it be?