The standard layout of the keys on the Touch-Tone telephone was the result of research of the human-engineering department at Bell Laboratories in the 1950s under the leadership of South African-born psychologist John Elias Karlin (1918–2013), who was previously a leading proponent in the introduction of all-number-dialing in the Bell System.
This research resulted in the design of the DTMF keypad that arranged the push-buttons into 12 positions in a 3-by-4 position rectangular array, and placed the 1, 2, and 3 keys in the top row for most accurate dialing. The remaining digits occupied the lower rows in sequence from left to right, however, placing the 0 into the center of the fourth row, while omitting the lower left, and lower right positions. These two positions were later assigned to the asterisk and pound key when the keypad was expanded for twelve buttons in 1969.
The DTMF keyboard layout broke with the tradition established in cash registers (and later adopted in calculators and computers) of having the 0 key at the bottom and the remaining keys increasing in rows above. This was due to research conducted by Bell Labs using test subjects unfamiliar with keypads. Comparing various layouts including two-row, two-column, and circular configurations, the study concluded that while there was little difference in speed or accuracy between any of the layouts, the now familiar arrangement with 1 at the top was the most favorably rated.
Josh was working on the development of a microprocessor controlled keypad decoder when he decided that it might make an interesting feature of a field puzzle in a mystery Geocache.
This is a two stage puzzle cache which requires some investigation prior to visiting the first stage which is at the posted coordinates. One must determine a five digit code which is to be entered into the keypad in the first stage. The order of the digits are A B C D E. There are two opportunities for one to find the numbers.
The numbers can be found at OR The numbers can be found at
(A) N42 06.542 W83 20.108 (A) N34 48.440 W82 49.242
(B) N42 06.350 W83 20.135 (B) N42 48.699 W83 40.524
(C) N42 06.392 W83 20.711 (C) N44 44.406 W67 18.996
(D) N42 06.677 W83 20.387 (D) N30 22.959 W86° 24.421
(E) N42 06.578 W83 20.332 (E) N43 11.627 W74 33.038
The digits must add up to 27
After being confident of your code go to the first stage and open the box. Push the start button and enter the code on the keypad. If the code is correct you will learn how to find the final stage. Note: If the code you entered is not correct you will have to wait about 15 seconds then push the start button and try again.
UPDATE: The mile marker referenced in the puzzle stage is missing. Please use the orange marker on the south side of the paved trail in place of the missing post. See the 3/3/2021 picture in the gallery
This cache is located within Oakwoods Metropark, a part of the Huron-Clinton Metropolitan Authority park system. A Metropark Vehicle Entry Permit is required: Annual Permit $35. Senior (62+) Permit $21. Daily Permit $10.
For General information please call 810-227-2752 800-47-PARKS. Or visit our website at WWW.metroparks.com.
All park rules and regulations apply. Park in parking lots only.
Dogs are allowed in this section of the park.
VERY IMPORTANT: THE HOURS FOR OAKWOODS METROPARK ARE FROM 8:00 AM TO DUSK. |
Please replace the box the way you found it.
CONGRATULATIONS TO:
First to Find: Hooked On U
Second to Find: GoldDogs
Third to Find: Paddling Pirates
The permit for this cache was renewed prior to the 4/15/2021 deadline and again was approved by Kevin Arnold | Southern District Interpretive Services Supervisor Huron-Clinton Metroparks on 04/13/21