1588 replies to this topic

[Deveshpande]

Does anyone here have instructions/video to lubricate the motors and the bearings ?

[apfever]

Yes they crack off with age, I've replaced a bunch over the years. I reinforce the ones I make. 

There are forum entries on maintanance. 

 

Not the string to discuss these aspects in detail. This thread needs to be kept to registry entries with only a few comments on an entry. Otherwise this thread will get derailed - especially in this forum.

Edited by apfever, 01 September 2021 - 06:37 AM.

[DogWatch]

Quite a find, and a unique story. From appearance it is low low mileage.

 

At first glance, all looks correct for the period. The only thing which struck me as not having seen before was the 3 knobs holding the wedge to the tripod. Did you get a power chord?

 

I wish I had advice for motors that have not been run in 40 years, as it's certain that if it were possible to lubricate them, they would last better than use after being dry so long. Also that the lubes of bearings and gears in the base too would be helpful. Gentle exercise of the focus knob between extremes should be sufficient for the main focus.  You may find the DEC knob stiff. If so, clean with alcohol and re-lube with a drop of fine oil.

 

Hopefully you got some eyepieces to begin with. 

 

Best of luck, Thanks for registering.

Thanks for your comments.  Yes the standard grey power cord was included, though I haven't plugged it in yet.

Several eyepieces were included:

Celestron 25mm Kellner

Celestron 40mm Kellner

TeleVue 10.5mm Plossl

TeleVue 17mm Possl

TeleVue 1.8x Barlow

and a Celestron Star Diagonal (marked as RFA but appears to only have the right angle prism inside) 

 

I would appreciate any comments regarding these eyepieces and any suggestions of ones I should acquire to fill out my kit. I know this is not the thread for eyepiece discussions, could someone point me to the right/ best thread for these questions regarding the C8?

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[B 26354]

I got a set of of those six-serration "flowerette" knobs for my '77 C8, shortly after buying the scope, new... and I still have them. Three to attach the wedge to the tripod (as shown in DogWatch's photo), and three to attach the fork-base to the wedge. There's also a seventh one (along with a few of the two-winged ones)... but the tripod and wedge are now long gone, and I honestly can't remember what the seventh knob's function was. Its bolt has the same length and threading as the two-winged altitude-adjustment bolts on the wedge, which also appear in DogWatch's photo.

 

And for the life of me, I can't recall where I got the set. Had to have been from an ad in S&T... but whether they came from Edmund or Bob's Knobs or someplace else, I'm not sure. Probably Bob's.

[DogWatch]

I got a set of of those six-serration "flowerette" knobs for my '77 C8, shortly after buying the scope, new... and I still have them. Three to attach the wedge to the tripod (as shown in DogWatch's photo), and three to attach the fork-base to the wedge. There's also a seventh one (along with a few of the two-winged ones)... but the tripod and wedge are now long gone, and I honestly can't remember what the seventh knob's function was. Its bolt has the same length and threading as the two-winged altitude-adjustment bolts on the wedge, which also appear in DogWatch's photo.

 

And for the life of me, I can't recall where I got the set. Had to have been from an ad in S&T... but whether they came from Edmund or Bob's Knobs or someplace else, I'm not sure. Probably Bob's.

One of the plastic "winged" covers on the alt adjustment screws is cracked and brittle, not long for this world.  The other is not cracked but looks brittle also.  I expect I will be looking to replace them soon.  Where did you get your extras?  Also, I can't find the single bolt described in the manual for attaching the OTA directly to the tripod without the wedge...ideas?

Thanks!

[B 26354]

One of the plastic "winged" covers on the alt adjustment screws is cracked and brittle, not long for this world.  The other is not cracked but looks brittle also.  I expect I will be looking to replace them soon.  Where did you get your extras?  Also, I can't find the single bolt described in the manual for attaching the OTA directly to the tripod without the wedge...ideas?

Thanks!

PM sent.    

[Kasmos]

It also looks like the wedge has also been fitted with some kind of T-head bolts. Celestron was probably still supplying all of the mounting hardware with hex head bolts at that time. While they didn't include user friendly knobs at least the hardware was stainless steel. My '79 C8 and 79 C90 is all hex head . My '82 C5 has knobs only on the tripod wedge connection but it doesn't help since my brother bought the wedge and tripod separate from the scope. In any case, I'm now curious to see how they are consructed and how many serrations those knobs have. 

[BYoesle]

I've inherited Serial No. 800248 - it's missing some parts and has some previous mods, but the optics/coatings are still pretty not bad. Considering a refurb, or possible corrector re-spacing to see what the real-world results could be ;-)

 

 

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[RSX11M+]

I've inherited Serial No. 800248 - it's missing some parts and has some previous mods, but the optics/coatings are still pretty not bad. Considering a refurb, or possible corrector re-spacing to see what the real-world results could be ;-)

Ordinarily, keeping a vintage C8 in original condition would be encouraged. However, considering the mechanical condition and vintage of your scope, I think it's a good candidate for the experimentation you propose.

 

• We believe the units in this SN range to have undergone production revisions to return manufacture to it's previous level of quality after a fall-off. Modifications should therefore, not suffer from a bad starting point.
• This era of production is relatively common, and the instrument would not lose any special collector value were it further modified.
• The components added to the DEC drive and RA should be removed and saved - they may be useful to others or have value.
• I anticipate you will remount the OTA, so the condition of the fork and base is relatively unimportant in the long term. Short term they should be functional enough to evaluate any changes.

 

If you would - please provide the Motor Dates and Optics number prior to separating the OTA from the mount so the association won't be lost. These data points can be important to the Registry, especially this early in the 8xxxxxx serial number change. Yours is the 3rd unit we now have after that change and represents what is "typical" very well. 

 

• The etched optics number is located on the face of the corrector, beneath the retaining ring at the 3:00 o'clock position facing the assembly, as in your first image.
• Motor dates are the final numbers stamped on the motor's side beneath the covers. (Usually "mm-yy" format)

 

 

Enjoy the freedom to experiment. It isn't often one can do so without remorse on one of the vintage C8s. Personally, I'd save the base and forks just in case some notariety becomes evident, but know they do have some value if sold to others and should not be discarded.

 

Thank you again for registering, this scope was not previously known to the registry and information in this era is very helpful.

 

I encourage you to start a forum thread of your own to share your progress as you make and evaluate changes. 

[BYoesle]

Optics Number: 4193

 

 

Motor dates are 10 & 11 - 77

 

 

We believe the units in this SN range to have undergone production revisions to return manufacture to it's previous level of quality after a fall-off.

Could you please elaborate on this a bit more or link to a reference? I had heard there were optical quality issues with ramped up production near the return of Haley's Comet in 1986, but wasn't aware of issues in the earlier production. And to clarify you appear to be stating by this specimen's circa 1978 production was back to specification?

 

And if you don't mind, I'd like to know if there is a preferred method of removing the corrector cell and mirror cell from the tube itself - they seem rather firmly affixed to each other.

 

Thanks 

Edited by BYoesle, 02 September 2021 - 06:10 PM.

[CHASLX200]

Thanks for your comments.  Yes the standard grey power cord was included, though I haven't plugged it in yet.

Several eyepieces were included:

Celestron 25mm Kellner

Celestron 40mm Kellner

TeleVue 10.5mm Plossl

TeleVue 17mm Possl

TeleVue 1.8x Barlow

and a Celestron Star Diagonal (marked as RFA but appears to only have the right angle prism inside) 

 

I would appreciate any comments regarding these eyepieces and any suggestions of ones I should acquire to fill out my kit. I know this is not the thread for eyepiece discussions, could someone point me to the right/ best thread for these questions regarding the C8?

The green box Tele Vue stuff is the best stuff ever made. Love the Circle NJ eyepieces.

[Don W]

Can we please stay on topic? This is the C8 Registry, not a general chat thread.

[RSX11M+]

Optics Number: 4193
 
Corrector SN.jpg
 
Motor dates are 10 & 11 - 77
 
Motor 1 date.jpg
Motor 2 date.jpg
 
...

Thank you for the additional data points. Yours may be the first reliable optics number we have in the 8000xxx series. Motor dates won't help much in determining a manufacture date - '77 motors appear in scopes from April of that year all the way into early 1980 scopes. Between serial number, optics and motors - your scope is consistent with 1979-1980 manufacture, but we cannot be certain.

PM sent regarding other inquiries.

Thanks again for the follow-up.

 

 

[jotapeh]

Hey everyone. Long time lurker but had to register after I picked up one of these beauties locally.
 
I have picked up unit 802167. Came with what I believe is its original purchase receipt from Oct 22 1979, from Astro Technics in Vancouver, BC for $1,065 Canadian. Has original wedge but missing several of the original bolts. Have not yet tested the motor as the power cord is missing as well.

 

[RSX11M+]

Hey everyone. Long time lurker but had to register after I picked up one of these beauties locally.
 
I have picked up unit 802167. Came with what I believe is its original purchase receipt from Oct 22 1979, from Astro Technics in Vancouver, BC for $1,065 Canadian. Has original wedge but missing several of the original bolts. Have not yet tested the motor as the power cord is missing as well.

 

c8sn.jpg

 

 

We seem to have a lot of these early 8xxxxxx series turning up lately. I keep thinking we're winning the lottery- This scope was not previously known to the registry.

 

An original purchase receipt is unusual, and special, please preserve it. It establishes an upper-bound date for manufacture, which helps us a great deal.

 

Your imgur photos show the unit to be in very good cosmetic (no pun intended) condition, and it appears to have features consistent with the receipt date and by it's serial number. I don't see many of those tripods, perhaps someone will comment if it is OEM.

 

A sale in North America would suggest 110v 60cy motors, but it's worth a look to confirm. (this doesn't usually require disassembly) Please post it's motor date-suffix if you go to the trouble to look.

 

We hope it works as good as it looks, Thank you for registering.

[jotapeh]

We seem to have a lot of these early 8xxxxxx series turning up lately. I keep thinking we're winning the lottery- This scope was not previously known to the registry.

 

An original purchase receipt is unusual, and special, please preserve it. It establishes an upper-bound date for manufacture, which helps us a great deal.

 

Your imgur photos show the unit to be in very good cosmetic (no pun intended) condition, and it appears to have features consistent with the receipt date and by it's serial number. I don't see many of those tripods, perhaps someone will comment if it is OEM.

 

A sale in North America would suggest 110v 60cy motors, but it's worth a look to confirm. (this doesn't usually require disassembly) Please post it's motor date-suffix if you go to the trouble to look.

 

We hope it works as good as it looks, Thank you for registering.

My pleasure to be here. I would not have pulled the trigger on purchasing this had I not seen the robust community here.. since you've noted the receipt is special, and because paper from 1979 can only last so many years, here's a photo.

 

 

I may have it framed for preservation's sake.

 

The motor (imgur link) is plated 110V 60Hz, and stamped "Synchron® Made in U.S.A." with blue light gauge wiring. Plug appears to be a standard 3 prong North America power supply cord. I am hesitant to supply mains power to it until I read up more on maintenance of these units.

[B 26354]

I have picked up unit 802167. Came with what I believe is its original purchase receipt from Oct 22 1979, from Astro Technics in Vancouver, BC for $1,065 Canadian. Has original wedge but missing several of the original bolts. Have not yet tested the motor as the power cord is missing as well.

PM sent.

[RSX11M+]

My pleasure to be here. I would not have pulled the trigger on purchasing this had I not seen the robust community here.. since you've noted the receipt is special, and because paper from 1979 can only last so many years, here's a photo.
 
c8_receipt.jpg
 
I may have it framed for preservation's sake.
 
The motor (imgur link) is plated 110V 60Hz, and stamped "Synchron® Made in U.S.A." with blue light gauge wiring. Plug appears to be a standard 3 prong North America power supply cord. I am hesitant to supply mains power to it until I read up more on maintenance of these units.

Too bad your imgur photo isn't published here, but I'll take a whack at describing it here to discuss.
 

1) The "Synchron..." nomenclature is stamped on the top (or bottom - as it is mounted upside-down in the scope base) and the 110v 60cy is on the motor's side, part of an extended stamped number, which has a mm-yy date at the very end. (usually near where the blue wire enters - ref pic below) That date is of interest, as we track them in the registry whenever it is supplied. Your "original receipt" provides provenance, and coupled with a motor date - helps us understand things about production in the era, and aids in dating other scopes.
 
2) Looking closely at your last photo (on imgur) I can see that the power recepticle appears to be a standard "instrument lead" which has three, flat-bladed prongs - slightly offset, in a rectangular socket with two angled corners. The arrangement allows only one cable orientation and is thereby polarized.
 
That type of power lead is not customary, and is not present in any of my scopes from this period. I wonder if is has been retrofitted by a caring and somewhat talented individual - aftermarket, or if this is a production variance I'd not noticed, perhaps at the 8xxxxxx juncture. The ones I have seen look like this... 
 

-Three round prongs (offset) in a socket well with round ends. (these images are from a C90-Astro base)

I encourage you to start a thread of your own to seek proper help with some basic maintenance tasks that will restore it's function and prolong the motors' lives. I'm glad you decided to become a member of the community of C8 owners, and am humbled we may have played a part.
 
Welcome, and thank you.

 

Update:

 

Can you make anything of the penciled in date on the receipt? (2-16-87)

Edited by RSX11M+, 09 September 2021 - 07:02 PM.

[Kasmos]

Too bad your imgur photo isn't published here, but I'll take a whack at describing it here to discuss.
 

1) The "Synchron..." nomenclature is stamped on the top (or bottom - as it is mounted upside-down in the scope base) and the 110v 60cy is on the motor's side, part of an extended stamped number, which has a mm-yy date at the very end. (usually near where the blue wire enters - ref pic below) That date is of interest, as we track them in the registry whenever it is supplied. Your "original receipt" provides provenance, and coupled with a motor date - helps us understand things about production in the era, and aids in dating other scopes.
 
2) Looking closely at your last photo (on imgur) I can see that the power recepticle appears to be a standard "instrument lead" which has three, flat-bladed prongs - slightly offset, in a rectangular socket with two angled corners. The arrangement allows only one cable orientation and is thereby polarized.
 
That type of power lead is not customary, and is not present in any of my scopes from this period. I wonder if is has been retrofitted by a caring and somewhat talented individual - aftermarket, or if this is a production variance I'd not noticed, perhaps at the 8xxxxxx juncture. The ones I have seen look like this... 
 
motor and socket c90.jpg
-Three round prongs (offset) in a socket well with round ends. (these images are from a C90-Astro base)

I encourage you to start a thread of your own to seek proper help with some basic maintenance tasks that will restore it's function and prolong the motors' lives. I'm glad you decided to become a member of the community of C8 owners, and am humbled we may have played a part.
 
Welcome, and thank you.

That flat blade socket is a much later modification likely done by an owner who could not find a proper powercord. The dead give away is the combination slotted/phillips screws holding it. I don't remember screws like that even being available in the 70s.

[RSX11M+]

That flat blade socket is a much later modification likely done by an owner who could not find a proper powercord. The dead give away is the combination slotted/phillips screws holding it. I don't remember screws like that even being available in the 70s.

With permission of the OP, this is the image of how 802167 appears today.

As you can see, it's an exemplary job of modification, if it is that.

 

I'll assume it isn't original unless we receive comments to the contrary.

[RSX11M+]

That flat blade socket is a much later modification likely done by an owner who could not find a proper powercord. The dead give away is the combination slotted/phillips screws holding it. I don't remember screws like that even being available in the 70s.

To share my thought process -

 

Instrument leads had appeared by the 1970s. I recall first noticing them on high-end hp test equipment of the era circa 1978. The hp-85 computer in 1980, and certainly the first IBM PC in 1981 used them - whereupon they entered "ubiquity". So based upon this alone, it was not out of the question this could be original, unless this is a solitary example. (read on)

 

As for the fasteners, I believe those to be cylindrical-head screws with combination Slot and Torx tooling. Torx has been growing in popularity since it's introduction in 1967, though I cannot say when I first noticed a combination screw.

 

So, while my inclination is to agree that it's a mod, my experience in manufacturing says - not so fast. Given Celestron's trials and tribulations, I do think it unlikely. However it may also be an escapee from engineering - not the first time such a raid took place in the interest of making shipments (think "clean the kitchen scope") or perhaps subsequent factory maintenance?

 

I'd like to wait before calling this one, but as previously stated I'm counting it as a mod. If jotapeh has occasion to open the base later as a result of say, cleaning and lube, it might help to get a photo of the wiring. However, such a responsible mod could have been done well on the inside too.

 

 

Anyway, thanks for the input. With you and me, that makes 3 votes to 0 for "mod". (B 26354 too)

[Kasmos]

I'm fairly certain it's a mod. I did a google search for 3 prong socket connection and this came up

I posted this second image so you could see the height of the raised rim of the socket

 

I had noticed what appears to be file marks before searching for the socket.

The raised rim was likely filed off so it would mount flush to the inside.

(I really doubt a manufacturer like Celestron would take the time to do something like that)

And there's a good chance the screws are held on the inside with small nuts.

 

After my last post I noticed the screws looked more like a combination Slot/Square head.

A square head screw is called a Robertson.

 

Another search revealed this:

 

https://toolguyd.com...rewdriver-bits/

 

While I could not find info on the screw's origins, the ECX driver appears to have not been invented until about ten years ago:

 

https://www.electric...ecx-bits.27634/

Edited by Kasmos, 10 September 2021 - 02:23 AM.

[jotapeh]

I do agree this is a mod, although I think it was done by a shop here in Ontario in the 80s. Here's why:

 

For what it's worth "Slotted Robertsons" have been around since the 1930s at least ... Robertson drive screws (and combination machine screws thereof) are popular here. Probably a little bit because Robertson was Canadian. 🇨🇦

 

The 3 prong socket shows marking "Made in Japan". Most of these are made in China now.

 

It is also stamped "CSA" which means it meets Canadian Electrical Code. This is not definitive, but it is common nowadays that electronic parts like light switches, plugs, etc.. simply be stamped "UL" which is not sufficient for Canada but does meet US standard.

 

On a purely speculative note, the connection is done with a nice shiny solder connection. A common skill in the Radioshack heyday of the 70s/80s. Not so sure about today.

 

Digging through more of the pile of papers I was given with this, most of which are simply recent photocopies of the original manual.. I found another receipt tucked away dated Dec 9 1980. This one from Focus Scientific Ltd., a telescope shop in Ottawa, Ontario. Itemized on this receipt:

 

• 1 T-Ring #20-0009
• 1 T-Adapter #22-3025

 

I don't know what these parts are exactly or what the item numbers signify. Worth noting although Focus Scientific exists in Ottawa today, it is not at the same address.

 

There is another interesting pamphlet from Focus Scientific Ltd included as well, with the same date we saw on the receipt in pencil, but this time in red ink (2-16-87). Perhaps this was some kind of warrant verification on this date, or perhaps the modification noted above happened then..

 

Oh yes, before I forget, you asked for the motor date. I cracked open the base and everything looked relatively clean. The motor does say 110v 60cy. If I'm reading the date correctly, this is from Feb 1979. So only about 8 months between the motor manufacture and purchase by the end consumer here.

 

 

That's all I have for now. I hope these anecdotal facts and speculations have proven helpful regarding the history of this specific unit.

[pierce]

fyi, the original cords for these scopes with the oval connector and round pins can be found by googling for 'vintage HP instrument power cord', or "belden PH163", they were used on test equipment in the 70s before the modern IEC320-C13/C14 cord sets became ubiquitous.

 

A T-Ring is a universal threaded adapter for cameras, you combine it with a t-ring-adapter for a specific camera lens mount (canon, nikon, etc).. 

Edited by pierce, 10 September 2021 - 02:15 PM.

[B 26354]

fyi, the original cords for these scopes with the oval connector and round pins can be found by googling for 'vintage HP instrument power cord', or "belden PH163", they were used on test equipment in the 70s before the modern IEC320-C13/C14 cord sets became ubiquitous.

Belden stopped making these chords a while ago. They are generally almost impossible to find.

 

As it happens, there are three available from a California seller on eBay:

 

https://www.ebay.com/p/19031315127

 

And apparently, a seller on Amazon, located somewhere in the Far East, is making them... at twice the price.

 

https://www.amazon.c...3/dp/B093LSZX55

 

Edited by B 26354, 10 September 2021 - 03:25 PM.