GPS Quiz #3 - It's about time Mystery Cache

The Cache is not at the coordinates listed above! Don't go there!

Besides positioning, the other major function of GPS is to give an accurate time reference. It has been called 'the atomic clock in the sky' and it is used by many different organizations for many different purposes: synchronizing television feeds, coordinating bank money transfers, sending email, scheduling airline takeoffs and landings and even regulating the power grid.

The first two GPS quiz caches in this series (GPS Quiz #1 and GPS Quiz #2), were fairly straightforward. This one is too... provided you can answer the following 'timely' questions.

1. What Colorado phone number you would call to hear the phrase "At the tone, (xx) hours (yy) minutes coordinated universal time"?
   Neat fact: If you call at 14 or 15 minutes past the hour, you will also hear a GPS system status message.
2. This facility also broadcasts the above anouncement on several frequencies.
   What is the frequency (in MHz) broadcast by the antenna located at:
   40° 40' 47.8" N 105° 02' 25.1" W
3. What is the base frequency (in Hertz) of the clock that they use at that facility, a frequency also famous for being the international basis for the second?
4. GPS satellites also carry an alternate Rubidium clock oscillator that is less expensive and has a different base frequency.
   What is the resonance frequency of 87-Rubidium oscillator? (According to NIST ^{see footnote 1})
5. What is the base frequency (in Hertz) of the clock used in most "quartz" wrist watches?
6. The GPS system records it's time in Weeks and Seconds. Many will recognize the phrase "remember 9/11". But to GPS 9/11/2001 occured in GPS week 1131, (after accounting for an event called GPS week rollover). A notable space disaster occured during GPS week "911".
   What date did this occur (mmddyyyy)?
7. When will the next GPS week number rollover (to GPS week 2048) occur? (mmddyyyy)
8. In addition to the GPS week, the time kept by GPS is indicated in 'GPS seconds'.
   What is the proper "GPS seconds" integer number for the start of an event called "Friday's after Five" at a Greenwich Pub in the UK?
9. What is the Modified Julian Date (5 digits) of the day when the most recent leap second occured? ('most recent' is based on the date that this cache was placed, just in case they decide to add another leap second anytime soon.) [Hint: This number is a palindrome]
10. You may be suprised to know that the GPS network clock does not adjust for leap seconds. The GPS satellites just tell your receiver to how to properly adjust the displayed time to account for these leap seconds.
    As of the most recent leap second, how many seconds was this adjustment? (Remember, GPS time did not start until 1980.)

^{footnote 1: The value of the Rubidium-87 resonance frequency has been measured more precisely since the time that this cache puzzle was placed. NIST now lists the updated resonance frequency in their "Time and Frequency Glossary" as the value that has been recommended by the BIPM as a secondary representation of the SI second. This puzzle uses only the digits before the decimal point. If you find a value that ends in "610", subtract 2 Hz to get "608" and now you are using the old value that was the best estimate for the Rubidium-87 resonance frequency when this cache puzzle was created.
footnote 2: Consider the hide date of the cache (and thus the date that I wrote this puzzle description when calculating any answers that require you to answer things about "most recent" events.}

Once you answer the 10 questions above (all of which have integer-only answers) then perform the following simple math on those numbers and fill in the single digit results for each calculation into:

1. ___ sum of all digits, then subtract 33
2. ___ subtract 7
3. ___ sum of all digits, divided by 45
4. ___ sum of all digits, minus 51
5. ___ sum of all digits, minus 20
6. ___ subtract 20 from the 'dd' part.
7. ___ subtract 2013 from the 'yyyy' part.
8. ___ divide by 164400 (result will be an integer)
9. ___ difference between 1st and 2nd digits of this number
10. ___ subtract 8 thus giving you the UTC-to-GPS time offset as of Jan 1, 1990, when GPS turned 10 years old.

Quiz #3:
Oh - you're not done with the quizzing just yet!
Be sure to take a sheet of paper or your own personal adventure log book (or the back of the printout for this cache would work as well), because you may want to make note of all the information and questions on GPS Quiz card found inside the cache. (Personally, I find my camera handy for things like this...) The questions on Quiz #3 are for your further study of the amazing system that we use to play this game. You will be tested on this material at some point in the future...

You can check your answers for this puzzle on Geochecker.com. North Carolina Geocachers Orginization