Pat,
Here are the reset instructions for the THF6A.
It should get you out of your dilemma. Be warned you will have to input many
things after the reset.

Written by Lynn N8LXK corrections to [log in to unmask]

Has your th-f6a lost its beep and you don't have sighted help available?
The following procedure may repeat may work in restoring it. This will cause
the menu settings to be restored to their factory defaults. You will lose
any things that are not defaults. These steps should only be attempted if
you are really desperate. Since you have been warned.
*1. Turn radio off by using power button, [When off pressing the MONI key
does not cause the radio to unsquelch.]
*2. While holding the f key [the key in the top right corner] down push the
power on button.
*3. Slowly release the f key and then the power key. Radio beeps here
*4. If the beep is off, you won't hear anything, however it's not necessary.
*5. Turn the tuning knob 2 clicks in the clockwise direction.
*6. Move the multi button to the right.
The radio's menu functions should now be restored to their defaults. [It
should now beep like it used to]

Lynn
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