Motorola ASTRO Digital Spectra Plus - Page 174

September 5, 2008 6881076C25-E
4-32 Troubleshooting Procedures: Power Amplifier Procedures
U0500
1 000000
Ground
20 3.2
Control AMP Input
3 000000
Control AMP Input (not used)
40023.2
Control Voltage Limit (cutback at 3.3 V)
50 0
N.C.
6 1.5 3.0 4.5 1.5 3.0 4.5
Power Set from D-A (max power at 1.5 V)
7 0 0 1.5 3.0 4.5
Power Set Buffer Out
8 0 1.3 3.5 6.0
Coupler Buffer Out
9 0 1.3 3.5 6.0
Forward Detect Voltage
10 0 0
Reflected Power Detect (not used)
11 0 1.3 3.5 6.0
Same as pin 8 (not used)
12 0 0 1.2 6.0
Thermister Buffer out (increases as PA gets hot)
13 0 0 1.2 6.0
Thermister Buffer in
14 5.0 5.0
5-V Sense Input (follows pin 20 ±0.1 V)
15 4.9 5.0 5.7 4.9 5.0 5.7
5-V Current Limit (limits at 5.7 V)
16 5.0 5.7 6.4 5.0 5.7 6.4
5-V Series Pass Drive (6.4 at max current)
17 9.5 9.6 9.9 9.5 9.6 9.9
9.6-V Sense Input
18 7 7
5-V Reg. Compensation Capacitor
19 5.7 5.7
N.C.
20 4.9 5.0 5.1 4.9 5.0 5.1
5-V Reference Input (UNSW5-V)
21 1.2 1.2
9.6-V Reg. Compensation Capacitor
22 0 0
N.C.
23 0.9 9.6 1.2 9.6
9.6-V Series Pass Drive
24 2.9 3.3
Regulator Enable/Compensation
25 ––––––
9.6-V Programming (N.C.)
26 0 0
N.C.
27 13.6 13.6
N.C.
28 ––––––
9.6-V Programming (N.C.)
Table 4-11. Power Control DC Voltage Chart (Continued)
LOCATION
RX MODE TX MODE
COMMENTS
LOW TYP HI LOW TYP HI