If you look in the installation manual of the KX-TA624 on page 4-42 setting up APT is explained for the TVS-50 and TVS-80. using a APT "Proprietary" Panasonic phone set.

The Installation Manual I am looking at is from 1999 PSQX1424VA KW0698KM7021APC

According to this online data at Telecomwarehouse the KX-TVA50 IS compatible with the KX-TA624.

Panasonic KX-TVA50 Voice Processing System (KX-TVA50)

Last edited by DonaldR; 04/10/23 06:10 PM.

"Most people don't have a sense of humor. They think they do, but they don't." --Jonathan Winters