odd TT problem

[Argyris]

A keypad on a WE Princess (looks like 1978 production) works fine except for the O key, which emits a high squeaky tone instead of the correct one. If I hold it down for a second or two, the tone wobbles slightly, and sometimes will produce the correct frequency for a moment so the call goes through.

What's going on here? Dirty contact inside the keypad? Something else?

[Phonesrfun]

Definitely sounds like dirty contacts.  In case you have't already seen it on the forum, you don't want to use any kind of sandpaper or emery cloth on the contacts.  Use something like a rough surfaced paper business card or card stock as the most abrasive thing to clean it with.  With the contacts closed slide the card in between the contacts and slide it back and forth several times.  Work your way around to all the switch contacts.

[AE_Collector]

How about the star and pound that share a frequency with the zero button?

Terry

[poplar1]

Pressing two adjacent buttons -- 8 and 0, or * and 0, 2 and 3, for example,  should produce a single tone. This will help determine whether it is the low tone (row) or high tone (column) that is having problems. The low tone is produced by the row, and the high tone by the column.

[Victor Laszlo]

What is the model number of the dial?