23
Table 2 – Radio Option Connector P3 Interface Description
DB-25
PIN
NO
(J100)
PIN
NO
(P3)
I/O
DESCRIPTION
2
1
---
Ground:
Audio Ground
5
2
I
Internal Speaker Input #1:
5W across Internal Speaker
6
3
O
Audio Amp Output #1:
Vo
≈
6.6 VDC
18
4
O
Audio Amp Output #2 to Internal or External Speaker
Vo
≈
6.6 VDC; 10W maximum across External Speaker
19
5
I
External Mic Input:
300-3000 Hz
Input level @ 1kHz for 60% of RSD: 82
±
28 mV
RMS
(if external audio source has Ro=600
Ω
)
Input level @ 1kHz for 60% of RSD: 41
±
14 m V
RMS
(if external audio source has Ro<1
Ω
)
7
6
I
External Mod Input:
5-10,000 Hz (3 db BW)
Modulation-Sensitivity: 4.2 kHz/Vrms ± 3dB
20
7
O
Switched DC Output:
Icc=500 mA Max
8
8
I
Push To Talk:
TX ON: Low
TX OFF: Open
21
9
I
Mic Hookswitch:
“Disable” or “Enable” is selected by PC Programmer
Hookswitch ON: Low
Hookswitch OFF: Open
9
10
O
Rx Discriminator Detect Audio:
20-4,000 Hz (3 dB Bandwidth)
75 m V
RMS
±3 dB into a 10K ohm load
22
11
---
Ground
10
12
I
Internal Mic Mute:
Mute ON: Low
Mute OFF: Open
23
13
O
Radio UnSquelch:
Squelch Open: Low
Squelch Close: High
RL = 4.7 kohms
11
14
Spare
