Northern Airborne Technology 250 - Manual (Page 18)

EQUIPMENT MANUAL 250-16-1
250/250-16-1 Page 9
The paging and receiver volume control pots required are linear taper, zero to 10,000 ohms, 1/2
watt or greater. Electrically, the pots are wired to provide maximum resistance to the Model 250
for full volume (fully clockwise rotation).
Table 1. Pin Identification
P40 (25-pin connector):
1 Left Speaker Out HI
2 Left Speaker Out HI
3 Left Speaker Out LO
4 Left Speaker Out LO
5 Left Speaker Out LO
6 28 VDC
7 28 VDC
8 28 VDC
9 Right Speaker Out LO
10 Right Speaker Out LO
11 Right Speaker Out LO
12 Right Speaker Out HI
13 Right Speaker Out HI
14 Left Speaker Out HI
15 No Connection
16 No Connection
17 Power Ground
18 Power Ground
19 Power Ground
20 Power Ground
21 28 VDC
22 Chassis Ground
23 No Connection
24 No Connection
25 Right Speaker Out Hi
P50 (37-pin connector):
1 Audio Common (except stereo)
2 PA MIC Hi
3 Paging Volume
4 Briefer Audio Hi
5 Stereo Switch
6 Left Input HI
7 Left Input LO
8 Right Input LO
9 Right Input HI
10 No Connection
11 Receiver Volume Control
12 No Connection
13 TV Switch
14 PSC Switch
15 ADF 2 Switch
16 ADF 1 Switch
17 ADF 1 Audio HI
18 TV Audio HI
19 PSC Audio HI
20 Audio Common (except stereo)
21 Audio Common (except stereo)
22 Audio Common (except stereo)
23 No connection
24 PA Key
25 Briefer Switch
26 No Connection
27 Audio Common (except stereo)
28 Audio Common (except stereo)
29 No Connection
30 No Connection
31 Smoking Sign Switch
32 Seat Belt Sign Switch
33 Cabin Call Switch
34 Hook Switch
35 PA Sidetone HI
36 Audio Common (except stereo)
37 ADF 2 Audio HI