Called Party Hold Device.
Arafiles,V P · Defense Technical Information Center (DTIC) · 1976
A Called Party Hold (CPH) device enables a telephone subscriber to hold an incoming call for tracing purposes. This paper describes the affects on AUTOVON of a commercially available CPH device that was in use at Scott AFB. It proposes a solution that will minimize AUTOVON interface problems using a simple dual tone, multi-frequency encoder-decoder scheme. (Author)