GS31B HF PA
Plate PI filter circuit:
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(MHz) C1(pF) C2(pF) La(t.) Lb(t.)
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28
51 270 2.1
0
24
61 330 2.5
0
21
63 360 3.3
0
18
70 400 4.2
0
14
102 560 5
0
10
120 650 5
3
7
165 870 5
5
3.5
300 1560 5
11
1.8 530
2600 5 22
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working Q = 9-12
La: D=60mm; l=60mm; n=5t.; dw=6mm.
Lb: D=60mm; l=100mm; n=22t.;
dw=2.3mm.
Lk: D=19.5mm; l=9mm; n=3t.; dw=1.5mm.
RFC: D=12mm; l=120mm; n=165t.; dw=0.7mm.
Use two RFC connected in series and mounted at
90 deg. angle, at least for 160m, 80m and 40m bands!
RHC: D=15mm; l=120mm; n=76t.; dw=1.5mm.
D - Coil inner
diameter
l – Coil length
n – Coil turns number
dw – Wire diameter.
Suppressor: D=25mm;
l=7mm; n=2t.; dw=2.3mm; R=47 Ohm/5W.
Cdc=2.2nF; U=10kV.
Ua=2.5kV at 0.8A
loading
Ug1=20-25V (adjust
for zero-drive plate current: 50-100mA)
Iamax=800mA
Pout=1.2-1.4kW
Pdrive=80-100W
All other data are
given on diagrams.
Dragan, YU1AW