|
|
|
|
|||||
|
||||||
From: Bill (no email)
Date: Thu Apr 21 2005 - 01:02:43 EDT
> Bill wrote:
> "> If I recall, the specs
>> are plus/minus 10 seconds error along the arc (0.17').
>> Unless you got a
>> dud, any value higher than 0.2' is highly suspect.
>
> And Alex replied:
> "Yes, I'm afraid it is a dud."
Frank responded:
>
> I don't buy it. That the certificate *says* the error is 10 seconds doesn't
> mean much of anything. Arc error is a correctable error and shooting
> lunars/star-star sights is probably the best way to detect it. Build your
> table, and
> then use it. And the fact that such error exists doesn't mean the instrument
> is a "dud". Correcting for arc error, once you have determined it, is every
> bit as easy as correcting for index error.
Frank
I was looking at the bigger picture (for a refreshing change of pace).
Celestaire, for example, speaks of accuracy by the lot. I would expect my
Atsra III B to be no worse than plus/minus 19" throughout the arc, maybe
better, despite any certificate. Any Cassens & Plath no worse than
plus/minus 9". Any SNO-T no worse than plus/minus 10". Those should be
upper limits. That is not to say lemons do not exist.
I have no cause to believe Soviet military gear would have been substandard
(although not petite ;-) If I accurately recall the post, some sort of cel
nav contest was won by a Polish sailor with a SNO-T--a long run of .2'
within known positions. If any of the list members have more details about
this seagoing cel-nav superstar, I would love to read them.
> I don't buy it.
Too bad. I have a gut feeling Alex would be willing to sell it if the
"right" offer came along. <G> Kidding aside, I believe him to be the sort
that will persevere and defeat any idiosyncrasies the SNO-T may posses.
Bill
|