Northern Airborne Technology PTA12-3xx - Manual (Page 27)

PTA12-300 POTS Telephone Adapter with NVIS Display
SM55-2 Installation and Operation Manual
Section 3 Rev: 1.00 Issue 4 Page 3-4
ENG-FORM: 806-0112.DOT
CONFIDENTIAL AND PROPRIETARY TO NORTHERN AIRBORNE TECHNOLOGY LTD.
3.3.2.6 Phones Volume ( ▲▼)
The UP/DOWN arrow button is a momentary digital rocker switch used to increase and decrease the
phones output volume when the PTA12-300 is in Call mode (i.e. the hook switch is active), or when the
hook switch is inactive but the Ringer Detect circuit is active.
The phones output volume increases by pressing the ▲ (up) arrow button and decreases with the ▼
(down) arrow button. There are a total of 32 steps from minimum volume to maximum volume and with
each ▲ or ▼ press, the display indicates the volume level (1 through 32). The display will show Volume
Up or Volume Dn (with the relevant volume level at the right of the display) until the next operator action.
The UP/DOWN arrow button may be used to adjust the phones volume by one step at a time by pressing
and releasing the button within one second. The level may also be used to auto-advance by holding down
either UP or DOWN for more than one second. In auto-advance mode the volume steps at approximately
five levels per second. Once at the top of the volume range (level 32) the control remains at 32 and does
not wrap around to level 1. The same is true for the bottom of the range (level 1). Once at level 1
subsequent presses of the DOWN arrow button does not change the level.
The last value of the phones volume is stored in non-volatile memory, and is retained upon power down.
3.3.3 Annunciators
The HOOK and HOLD annunciators are immediately to the left of the display, and the LNK and SYS
annunciators are immediately to the right of the display. They are green LED 'dead-front' text
annunciators, which means that they are not visible until they are illuminated.
3.3.3.1 HOOK and HOLD Annunciators
The functioning of the HOOK and HOLD annunciators is described in sections 3.3.2.2 and 3.3.3.3.
3.3.3.2 Satcom Annunciators
The other two annunciators, LNK and SYS, are only operational when the PTA12-300 is interfaced to an
STX100 satcom data communications port.
3.3.3.3 LNK (Satcom Link)
The LNK text will not be visible (LED off) if the satcom link is down and will illuminate green (LED on)
when the satcom link is established.
3.3.3.4 SYS (Satcom System)
The SYS text will not be visible (LED off) if the satcom system is busy and will illuminate green (LED on)
when the satcom system is available for voice.