Motorola Astro XTL 1500 - Table 6-2. TX and RX Audio Path Test Points for 1 Khz Sine Wave

6815854H01-A June 15, 2005
Troubleshooting Waveforms: XTL 1500 Waveforms 6-13
Table 6-2. TX and RX Audio Path Test Points for 1 kHz Sine Wave
(for VHF, UHF R1 and 700/800 MHz)
Typical O-Scope Measured mV p-p Volts
Test Point Description mV RMS mV/div LL
1
UL
2
DC Bias
TX Audio Path
MIC_HI 80 mV RMS input 80 mV 20 226 227 3 to 9
TP0200 MIC_PREAMP_IN 80 mV 20 220 227 1.42
TP0201 Preamp in, attn.-out 43 mV 10 100 122 1.42
U0201-1 1st op amp out
3
42 mV 10 97 121 1.42
TP0202 2nd op amp in
3
41 mV 10 97 121 1.42
U0201-7 2nd op amp out 41 mV 10 94 120 1.42
U0201-8 3rd op amp and filter out 40 mV 10 91 119 1.42
U0201-14 4th op amp and filter out 39 mV 10 88 118 1.42
TP0203 CODEC op amp in 38 mV 10 85 117 1.42
U0200-17 Buffered CODEC in 36 mV 10 82 116 1.42
C0904 5 CF Out 150 mV 50 400 700 1.42
R6782 MOD_IN at 3 kHz dev.
3
150 mV 50 400 700 1.5
RX Audio Path
4
TP0204 RX_FILT_AUDIO 318 500 849 953 1.42
TP0205 RX_AUDIO_IN 318 500 849 953 1.42
TP0206 AUDIO_PA_IN 39 10 92 130 1/2 A+
SPKR+ NON INVERTED PA out 7.74 Vbtl
5
2V 9.5Vpp 12.4Vpp 1/2A+
SPKR- INVERTED PA out 7.74 Vbtl
5
2V 9.5Vpp 12.4Vpp 1/2A+
1
LL = lower limit
2
UL = upper limit
3
Measurement depends on tuning parameters
4
1 kHz tone at 3 kHz deviation, -47 dBm
5
“btl” = bridge to load