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