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Serial Number Question

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#1 Orion68


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Posted 23 February 2014 - 05:49 PM

I have two recently purchased Questars, both used, and am not sure the year of manufacture for either one. one is a standard and one a duplex.

One was advertised as 1978 but I don't think that is possible since the serial number starts with a 6. The other one did not advertise the year.

The standard is #1-8126. Questar information suggests this is either 1981 or 1991. Not sure how to determine between the two.

The duplex is #6-CV-DP-6403-BB. On this one I am guessing 1976 since the cervit mirror was not used after 1978.

Any help dating these two is really appreciated.
Thanks, Tim

#2 Billydee


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Posted 23 February 2014 - 11:07 PM


Serial numbers from about 4000 to about 7500 were made in the 1970s. So serial number 6-6403 was made in 1976. The way they put the numbers on the base might make the 6 look like an 8 or the 8 look like a 6.

Serial numbers from about 7500 to about 9700 were made in the 1980s. So serial number 1-8126 was made in 1981.

The easy way to confirm all this is to just call Questar and talk to them. They will be glad to give you the exact birth date and add your name to the owners list for that serial number.

Duplex and Standard Qs are in the same serial number base (all Q3.5s).


#3 Orion68


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Posted 23 February 2014 - 11:22 PM

Thanks a lot Bill, much appreciated.
Best Wishes, Tim

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