Performance Checks: Transmitter Performance Checks Sec 1: 5-13
5.5 Transmitter Performance Checks
The following tables outline the performance checks for the transmitter.
Audio Output 
Distortion
Mode: Proj 25 Std
RF Control: Gen
Output Level: -47 dBm
Proj 25 Dev: 2.83 kHz
Code: 1011 Hz PAT
Meter: Ext. Distortion
Radio Tuner 
Software not used; 
Radio: Out of 
TEST MODE; 
Select a 
conventional 
ASTRO channel
PTT to OFF 
(center)
Meter selector to 
Audio PA
Spkr/Load to 
Speaker
Distortion < 3.0%
Residual 
Audio Noise 
Ratio
Mode: Proj 25 Std
RF Control: Gen
Output Level: -47 dBm
Proj 25 Dev: 2.83 kHz
Code:
A) 1011 Hz PAT
B) Silence PAT
Meter: AC Volts
As above As above Residual Audio Noise Ratio 
-45 dB
* These tests require a communications system analyzer with the ASTRO 25 test options.
Table 5-9.  Transmitter Performance Checks – APX 5000/ APX 6000/ APX 6000Li 
Test Name System Analyzer Radio Test Set Comments
Reference 
Frequency
RF Control: Monitor
Meter: RF Display
Display: Bar Graphs
Freq: Selected radio TX 
freq.
TEST MODE CSQ 
channel* or 
programmed 
conventional 
channel
PTT to continuous 
(during the 
performance 
check).
VHF: ±0.8 ppm
(±140 Hz)
UHF1: ±0.8 ppm
(±376 Hz)
UHF2: ±0.8 ppm
(±416 Hz)
700–800 MHz: ±0.8 ppm
(±696 Hz)
RF Power As above As above As above VHF: 1–6 Watts
UHF1: 1–5 Watt
UHF2: 1–5 Watt
700: 1–2.7 Watt
800: 1–3 Watt
Voice 
Modulation
(external)
As above. Set fixed 1 kHz 
audio level to 400 mV.
As above As above Deviation:
(12.5 kHz) ≥ 2.1 kHz, but 
≤ 2.5 kHz
(25 kHz) ≥ 4.1 kHz, but 
≤ 5.0 kHz
Table 5-8.  Receiver Tests for ASTRO Conventional Channels* (Continued)
Test Name System Analyzer Radio Test Set Comments