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Features
TAP-1 lets you attach an analog telephone to your consumer or
laboratory grade audio equipment or PC sound card using
standard RCA audio input and output jacks. There are three
jacks on the front of TAP-1. The RJ-11 "phone" jack is the
electrical equivilent to the wall jack that you would typically plug
your telephone into. Technically speaking, TAP-1 provides up to
70 milliamps of -48 volts DC to power your telephone and then
separates the telephone audio signal into transmit and receive
voice paths. This is similar in function to the line card on a
telephone company central office switching system. The RCA
jacks provide high quality transmit and receive voice paths to your
audio equipment.
The rear panel of the TAP-1 has three adjustments which are
accessible with a small, flat blade screwdriver. The
input level
adjustment controls the volume of the signal going through TAP-1
and into the phone. The
output level
adjusts the volume from the
phone to your audio equipment. The
null adjustment
is used to
fine tune the transmit / receive separation between the telephone
and the TAP-1. This is commonly referred to as trans-hybrid loss
or echo return loss.
Installation
1)
Connect a telephone to the front panel RJ-11 jack. DO
NOT CONNECT THIS JACK TO A TELEPHONE LINE.
2)
Connect a signal source (CD player, D/A converter,
signal generator..) to the
input
jack.
3)
Connect the TAP-1
output
jack to the input of your
equipment (amplifier line input, tape recorder input,
oscilloscope...).
4)
Plug in the supplied AC adaptor and apply power.
5)
Adjust the line input and line output volume controls to
suit your application.
Applications
A single TAP-1 can be used in applications such as:
+ phone testing and evaluation,
+ training ASR algorithms for phone line use,
+ simulating phone based services without actual
connection to a phone line.
Service Simulator Example
Input__ __Output
Computer simulating
a central office
Tap-1
