Figure 7-26. Hud4022A/Hud4025B Receiver Front-End Schematic (Sheet 2 Of 2) - Motorola ASTRO Digital XTL 5000 Detailed Service Manual

7-28
9.3V_FE
IF6251
9.3V
9.3V_FROM_FGU
5V
AGC/Attenuator circuit
5V
IF6257
5V
5V_FE
R3253
10K
Q3250
47K
47K
IF6258
5V
RF_ATTN_1_A
U3250 B(,1),A(,1)
AT267
C3272
470.p
C3262 C3263
R3274
GND
470.p
1.n 2 390.
B(,1),A(,1)
B(,1),A(,1)
B(,1),A(,1)
L3261
C3282
1.2u
470.p
B(,1),A(,1)
IF6253
B(,1),A(,1) B(,1),A(,1)
RF_IN
C3255 C3284
1.n 1.n
D3255
R3277
3.3K
IF6786
RF_ATTN_2_A
C3288 C3289
470.p 100.n
R3278
56.K

Figure 7-26. HUD4022A/HUD4025B Receiver Front-End Schematic (Sheet 2 of 2)

May 25, 2005
C3301 L3275
470.p 270.0n
B(,1),A(,1)
R3257
C3302
620.
470.p
B(,1),A(,1)
Q3254
C3312
0 B(,1),A(,0)
100.n
C3303
R3254
10.n R3259
C3256
4.7K 2.2K
470.p
C3264 C3259 C3299
39.000p 13.p 39.000p
D3251 B(,1),A(,1)
B(,1),A(,1)
B(,1),A(,1) C3936
B(,1),A(,1)
B(,1),A(,1) 1.n
C3300
D3252 C3257
62.00p 62.00p
D3256
B(,1),A(,1) B(,1),A(,1)
L3272
L3273
72.22n
72.22n
L3266
1.2u
C3260
1.n
Q3256
B(,1),A(,1)
R3280
5V
3.3K
R3273
3.9K
R3281
3.6K
Q3258
B(,1),A(,1) B(,1),A(,1)
B(,1),A(,1)
R3279
R3269
7.5K
56.K
Schematics, Component Location Diagrams, and Parts Lists: HUD4022A/HUD4025B (VHF) Main Board
R3255
62.
R3258
62.
B(,1),A(,1)
L3276 C3304 C3305
1.0u 10.n 470.p
B(,1),A(,1)
C3307 C3306
10.n 470.p
C3265
B(,1),A(,1) 1.n
B(,1),A(,1) B(,1),A(,1) B(,1),A(,1)
C3308
R3256 R3260
D3253
10.n C3309
51.
1.K 0 B(,1),A(,0)
10.n
R3271
B(,1),A(,1) D3254
75.
Q3255
B(,1),A(,1)
L3277
R3272
33. 10.0n
L3268 L3269
1.2u 1.2u
0 B(,1),A(,0)
R3265
9.3V_FE
10.K
C3266
B(,1),A(,1)
1.n
R3266
10.K
C3261
1.n
Q3257
9.3V_TO_IF
5V
R3275 C3267
390. 100.n
B(,1),A(,1)
L3270
C3270
1.2u 470.p
C3273
L3260 C3280 C3294
1.n 1.n 1.n
38.13n
B(,1),A(,1)
B(,1),A(,1)
B(,1),A(,1)
B(,1),A(,1)
C3281
C3276
9.1p
13.p
NP
NP
6881096C74-B