Look what I have - and its raining for a week

[miki63au]

G'day all,
I just received my new scope. It's a 12.5" F16 DK Cassagrain (thanks Mark to
educate me) from the 70's AO.
Well its raining so I could not tested but is sooo coool ;)
especially the rotary eyepiece holder.:D

However I just could not understand the drive and clutch mechanism.
Is there any one who has this eq mount?
Eventually I like to modify it, perhaps adopting it to
a Sky scan kit :screwy:
I have to get rid of the tangent arm DEC first.
It is not a true tangent arm, very rough and only
a couple of degrees.
The RA drive is a ac motor drive a brass worm true a right angle sprocket,
but the manual slo mo is again the same ex-centric wheel like the DEC axis.
I could not disassemble the clutch. If any one tackle that before could
you educate me please how to:help:
Thanks,
Mick.
33896

33897

33898

33899

[ballaratdragons]

Wow!!!! Great stuff Mick.

I love the Rotary multi-EP Eyepiece holder :eyepop:

Imagine all the Toucams I could put in it! :lol:

[citivolus]

Woah, that is one funky diagonal.

[mrsnipey]

Niiiice.

[g__day]

Very nice scope and way cool turret diagonal! BTW the octpus or turret diagonals I have seen online are anything but cheap!

http://www.observatory.org/turret.htm

[OneOfOne]

The first thing I noticed is that there doesn't seem to be enough counterweight! It has this huge cannon on one side and what looks like no more than 15kg or so of counterweight....and they made of lead or depleted uranium!:scared:

It looks like the drought is broken in your area for the rest of the year.

[miki63au]

Its a lead counterweights.
I like to install a DEC worm, I have a 6" one
but only 1:90 the reduction. Later I may save for
a Sky Scan kit with stepper motors, and make a gear train for
a 180 reduction. I think that what a eq6 has.
Any idea how to disassemble the RA clutch?
Clear sky,
Mick.

[centauri]

Holy Hell, now that's huge!
Who says size don't matter?
Nice pickup Mick

[Ric]

What a classic scope Mick, you'll get a lot of enjoyment from that one.

Cheers

[Aster]

Hi Mike,

Haven't seen one of them for twenty years. AOS stopped making them a year before I started with them. I see it still has the original Unitron Multi Eyepice Holder. Nice piece of equipment.

You can try Sydneys Telephone directory for Eric Witcombe, founder of AOS, but I have that feeling that he may not be with us anymore.

Have no idea myself how to take the RA/Dec appart. Never came across that type of mount for repairs in my 20 odd years with AOS.

Alexander

[netwolf]

A very nice instrument indeed. I inquired about this scope but when i was informed of the weight of the OTA i decide against it. I wonder how many are out there like this one.

Regards
Fahim

[miki63au]

Hi Fahim,
did you talk to Adrian?
The thing is, I the tube is huge and heavy.
Well above the EQ6 capacity. Originally I
was thinking if the mount is too hard to modify,
I just get the EQ6. Now I have it, no way... buga!
Well, just have to figure it out how to modernize the mount.

The other thing is the ota. With a cassegrain the sky flooding
and the central obstruction competing. The chap before Adrian
modified the baffle tube for the secondary. I will run the DK Cassegrain'
with a optical design program, and see if I can improve on it.

With the turret (2" prism) the back focus is big, and may be not optimal for
spherical aberration. Mind you, it is way cool 70's gadget, but its certainly not a "ETHOS" field of view!!! (30 deg most of them)

I have to get a 2" diagonal and a set of eyepiece with long focal length.
5000mm of primary focus, just imagine: the Ethos 13mm give ~370x
and close to the full moon field of view!!
Coma may be an issue.
But its raining for a week in Adelaide.

I will report back to the community when I has the chance.
(for give my lack of perfect English, I has trouble to get it right...)

Mick.

[netwolf]

Mick,

I made a mistake then, the one I was looking at was from QLD. But its looks like similar. The seller advised the OTA was 40-50Kg on its own. It was a 12.5" F20 or F15 (not sure) sold by Astro Optical back in the 75ish period. On a very heavy duty mount. I suspect probably the Goliath mount bigger brother of the Samson mount.

So thats 2 of these that we know of.

Regards
Fahim

[miki63au]

Yeah, I contacted that chap, it is the same scope, same mount!
The difference is that he's scope has a heavy alu cell.
Not sure about the f20 claim. He's ad was saying f15, and main I just got
apparently is f16. I don't know...
Will test it when the weather clears.

Mick.

[netwolf]

Well the add says F20 and the picture I received had 32cm F15 written on it, thats why i am not sure.

Regards
Fahim

[miki63au]

Fahim,
I was swapped my 12" GSO dob, and electronic test gear
for it. No money changed hand. I crave for a C14 go-to,
but at this stage of my life could not afford one...
Kids still eating the fridge, but not have a clue how to fill one,
plus the mordgage... etc. You get my drift. This is the best I could than
for the circumstances. I did not like the dob, coma and push-to....
In the city I can enjoy only the planets and the moon, and this scope
hopefully give me what the law's of physic aloud me to see,
until I fix my anti-gravity drive and ZPF power source and get a
one way ticket to Mars.... :) My daughter would be happy with that...
Cheers,
Mick.

[Alchemy]

big beastie you have there. going to be taking some pics with it soon i hope.
will look out for your posts.

[miki63au]

I like to use a ccd, it's 5000mm focal length
mean I not need any Barlow. First I have to make
a dual axis drive!
Any ATM-er did a conversion using ARGO-NAVIES,
and servo motors for a old eq mount like this?
Mick.

[netwolf]

Hi Mick,

solissydney Ken has a mount similar to yours with Argonavis on it, and he told me it required quiet a bit of work to get the parts machined etc. But Gary (maker of AN) may have a blueprint for it. I think it might suit your mount. His mount looks very similar to yours. But he also has worm gears on both dec and RA. Try sending solissydney a private message or email and also contact Gary.

Regards
Fahim

[miki63au]

Thanks Fahim, I just did that.
Mick.

[DavidU]

Jeez ! nice scope...... how did you find it??????

[miki63au]

Hi David,
from the local astro society's bulletin.
The chap advertised it, he's got a C14 now.
Mick.

[rumples riot]

Hey Mick,

glad to see you finally got a new scope. That mount is so much larger than the EQ6 you came to see at my place. You will have a bit of work to do to your new toy, but you are a smart guy and I am sure you can work it out.

Paul

[miki63au]

G'day Paul,
yeah, initially I was hoping the OTA is lighter,
so if It's too much trouble to modify the mount
just save for a EQ6 PRO. Well the OTA is around
25kg and 1.2m long 14" dia. I think even the G11
would have trouble with that.
This mount is solid, and 1.5" shaft is ok, not sure
about the drive. It's look like a 5" worm but because of the
peculiar clutch-setting circle assembly, I not able to check it.
Waiting for some one to rescue me with some idea!
Of course Adelaide is cloudy for a week, sorry about that Paul
and any one in Adelaide....
Report back when I have a chance.
Mick.