coax T/R switch
470k
390
0.68u
0.47u
150
20p
39p
1N916
K1
First LO (A5 ) 200 - 370 MHz in 18 steps of 10 MHz
RF AMPLIFIER ( A8 )
To 3d IF
(500kHz)
First & second IF
A2
2nd LO
17-26 MHz
PRC-41 RF parts
For heaters see power supplies sheet
9 dec 2017 kb
A1
A3
A2
V1
7077
V4
7554
V5
6442
V4
7554
V3
7554
V2
7077
V1
7077
1st LO
100
82
J2
150
10
33
+180V
17k
220k
680
330
680
J2
All relay contacts
shown in receive position
J9-J10
J3
J1
J2
J7
J1
J1
225-400 MHz
First IF
20-30 MHz
Z1
Z4
Z5
1 : 2
+13dBm
( 1Vrms)
470 p
2
2
470p
500
6p
4
20
20
2
2
20
2
22k
0.22
10p
Testpoint, 1M series resistor and
500pF feedtru not shown
51
10k
100
V2
7077
Z2
2
470 p
10
V3
7554
470
+190V
Z3
2
20 p
500 p
100
82
1k8
2k7
J3
J4
500 p
470
J5
J6
330
680
20p
9
2N1481
A1
19
-6.8V
to guard receiver
+26V
coax relay
3d LO
2.9-3.8 MHz
15k
470
A1
+190V
4k7
4k7
modulator
6
15
14
13
4 spare
1N251
4
J8
J11
0.7V
0.7V
1.7V
1.0 V
-2 V
-2 V
45mA
@Tx
+133V
+125V (Rx) / 190V (Tx)
No oven
100k
0.1V without signal
225 - 400 MC
Bandpass filter
+26V on Tx
4k7
10k
2k2
10u
5
20
+24V
-AVC
12
Ω
K1