I have forgotten the 3-letter code we set to open our "Supra" brand key lockbox. The dial has the 26 letters of the alphabet imprinted on it. Unfortunately, we have not used this lockbox for over 25 years. Is there a universal three-letter code which will open this key lockbox?

The best codes are here

Best Codes : 27 Steps (with Pictures) - Instructables

https://www.instructables.com > Living > Education
27 steps
1.
A1Z26The A1Z26 code is a very simple code. As you know there are 26 letters in the American alphabet so Z would equal 26 because it is the 26th letter in the alphabet.A B C D E F G H I J K L M N O P Q R S T U V W X Y Z 1 2 3 4 5 6 7 8 9 10 11 12 13 ...
2.
ASCII ASCII is a computer code that is similar to binary. Instead of using 1's and 0's like binary it uses the numbers from 1-256 A=65 B=66 C=67 D=68 E=69 F ...
3.
Atbash The Atbash code is just the alphabet backwards. For example A would equal Z. A B C

Different languages have different alphabets with differing number of letters. The English alphabet has twenty-six (26) letters.

I have just moved into a house that has a supra combination code key safe mounted on a wall outside the back door , it was put there by the first owner who died ,the second owner never used it and don't know the code,I just thought it would be handy to use as we are going away in June to France and its away of leaving a key in case the alarm goes off while away so a neighbour could deactivate it or the police so they don't have to brake down the door or if I get locked out I could have that key for emergencies so is there a way I could find the code for the safe please?

On a flip phone the left and right soft keys are under the display when you open the phone. We used to call them "snake eyes" back in the day. Usually they access the menus on the handset. Each of the other keys on the keypad correspond to letters of the alphabet just like the letters on your home phone. Pressing 2 key once for "a", twice for "b", etc.

the following denotes an addition, in which each alphabet stands for a particular digit, ... each alphabet stands for a particular digit, but no alphabet represents 3 and 4.MINE+LENS = LEAKS what does the letter "s" stands for and how? ...

Start by pressing ** and see what the display shows. If it doesn't show anything but beeps, then you have the wrong phone. Try looking for extension 101 or the first phone in the system.

When you find that phone and press program **1234, you'll go into programming. Dial 004 and press ENTER. If you press ENTER again, you'll be looking at extension 101, or you can dial an extension and be looking at a name. Now you spell out the name on the keypad using the letters and the arrow key if necessary and press ENTER (the center of the Navigator button) to store the name. Notice that the 4th time you press a 3 letter ALPHA key, you will get lower case letters. Punctuation is under the 1, * and # keys and Q appears under the 1 and 7 keys :-)

Next steps you to the next extension and you can just pick up the handset and set it back down to end programming.

Carl

NAME DISPLAY
NOTE: Display Dterm
A name with up to 16 characters can be entered to display the name on
other Dterm telephones when making a call.
• Press Speaker key, Receive dial tone.
• Dial the Name Assignment access code and receive special dial tone.
• Using the keypad, depress the key with the desired letter to display the
first letter on the key. The
display will indicate the
numerical designation.
Subsequent depressions will
advance through the letters
on that key. The Dial Pad Key
TABLE can be used as a
guide to indicate the key and
the number of depressions required to display numbers, letters, spaces
and periods.
• When the desired letter is displayed, depression of the Transfer key will
change the letter to a lower case letter (default is upper case). Depress
the Hold key to enter that letter and advance to the next entry.
• Repeat the previous two steps until the desired name is displayed and
entered

Letters are on the soft pad to the left of the number keys. Very tiny, so look close. You can also lift up the mylar sheet and remove the paper sheet.

About fixed dialing
If you enable fixed dialing number (FDN) mode, your device only makes calls to contacts on your FDN list. Your device can dial emergency numbers in FDN mode, even if the numbers are not in the FDN list. If your service provider plan includes SMS, you can also send SMS messages to contacts on your FDN list

so if you have this enabled chances are you have to turn it off.
this is how you turn it on so you should be able to use it as a guide to turn it off.



Turn on fixed dialing
1. In the phone options, click FDN Phone List.
2. Click the trackwheel.
3. Click Enable FDN mode.
4. Type the PIN2 code provided by your service provider.
5. Click the trackwheel.

or if you wanna keep it on and add friends to the fdn



Add contacts to the FDN list
1. In the phone options, click FDN Phone List.
2. Click the trackwheel.
3. Click New.
4. Type the PIN2 code provided by your service provider.
5. Click the trackwheel.
6. Type a name and a phone number.
7. Click the trackwheel.
8. Click Save.

and finally some shortcut keys:
To open the phone, press the Send key.
To end a call, press the End key.
To call a selected contact or phone number, press the Send key. To call a speed dial number, hold the assigned key.
To add an extension to a phone number, press the X key. Type the extension number.
To call your voice mail access number, hold 1.
To type a letter in a number field, hold the Alt key.
To type the first letter on a key, press the letter key once.
To type the second letter on a key, press the letter key twice.
To turn on or turn off mute using the Mute button, press the Mute button.
To turn on or turn off mute using the keypad, press the exclamation point (!) key.
To turn speakerphone on and off during a call, press the period (.) key.
To change the volume during a call, roll the trackwheel.

This works on the series E phones. It may or may not work on the series II.

1. Press the Speaker key (do not use the handset).
2. Dial the Name Assignment access code and wait for the special dial tone.
3. Using the key pad spell the name. Press each number until the letter appears.
4. When the correct letter is displayed Press the HOLD key. Pressing the HOLD key will lock the letter in place and advance to the next position.
5. Repeat steps 3 and 4 continue to spell the name.

Pressing the TRANSFER key will change the current letter to lower case.
Example to enter the name “Pat” press:
77 HOLD 22 TRANSFER HOLD 88 TRANSFER HOLD