JK Audio THAT-2 - Manual (Page 4)

4
Operation
The supplied adapter cable allows you to take the left
channel from a 1/8" stereo headphone or mono
microphone jack and attach it to the RCA jack on THAT-2.
Handset Type Switch
The three position switch on the front of THAT-2 selects
the type of microphone that is in the handset of your
telephone. When you push the Line In button in, THAT-2
replaces the handset microphone signal with a circuit that
must match the characteristics of the handset
microphone.
The Handset Type switch can cover the main three
microphone types, but keep in mind that there is no
industry standard for microphone types or characteristics
and therefore we cannot guarantee a perfect match with
every telephone. There is no way to tell which type of mic
is in your telephone handset. Simply use the position that
sounds best without clipping or signal break-up.
Switch Position Handset Microphone Type
A Electret
B Dynamic
C Carbon
Note: Not all telephones are built alike so we cannot
guarantee THAT-2 will work with every handset
design available. We designed the interface to
work with most popular designs.