PTA12-000 POTS Telephone Adapter Manual
SM55 Rev. 4.00
2.3.3
Cabling and Wiring
All unshielded wire should be MIL-W-22759 or equivalent. For shielded wire
applications, use Tefzel MIL-C-27500 shielded wire with solder sleeves (for shield
terminations) to make the most compact and easily terminated interconnect. Follow the
wiring diagrams in Section 2.5 as required.
Allow 3 inches from the end of the wire to the shield termination to allow the hood to be
easily installed. Note that the hood is a ‘clamshell’ hood, and is installed after the wiring
is complete.
All wiring should be at least 22 AWG, except power and ground lines, which should be
at least 20 AWG. Ensure that all ground connections are clean and well secured.
2.3.4 Internal
Adjustments
The following adjustments are accessible through holes in the side of the unit.
2.3.4.1 Internal
Trimpots
Rotating the trimpots cw will increase the level of the related
output, and ccw will decrease it.
LTS
adjusts keypad backlighting level from off to max
DTMF
adjusts DTMF level on POTS interface
S/T
adjusts sidetone level
RX
adjusts receive level on phones output
MIC
adjusts mic level on POTS interface
RGR
adjusts ringer level on both ringer audio and
phones output
2.3.4.2 Internal
Switches
RGR
(ringer select) on [down] ringer audio available on both
phones and ringer audio outputs
off [up]
ringer audio only available on
ringer audio output
*
FL
B
(
hook flash
) on [down] flash = 600 ms
±
10%
* One of FL A
or
FL B
must be selected ‘on’
for proper hook
switch operation
off [up]
600ms hook flash disabled
*
FL A
(
hook flash
) on [down] flash = 90 ms
±
10%
off [up]
90ms hook flash disabled
MIC
(mic bias)
on [down] mic bias supplied by PTA12
off [up]
mic bias not supplied
Page 2-2
Nov 12, 2003
ENG-FORM: 805-0106.DOT
CONFIDENTIAL AND PROPRIETARY TO NORTHERN AIRBORNE TECHNOLOGY LTD.
