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G8MNY > TECH 14.10.26 18:20l 33 Lines 1145 Bytes #10 (0) @ WW
BID : 7966_GB7CIP
Subj: 50ê - 72ê HF Balun
Path: JH4XSY<F1OYP<EA7HQL<ED1ZAC<EA2RCF<LU9DCE<VE3CGR<VE3TOK<VE3KPG<GB7CIP
Sent: 261014/0914Z @:GB7CIP.#32.GBR.EURO #:7966 [Caterham Surrey GBR] $:7966_GB
From: G8MNY@GB7CIP.#32.GBR.EURO
To : TECH@WW
Here is 1.2:1 balun for HF freq`s (Updated Mar 05)
(8 Bit ASCII graphics use code page 437 or 850, Terminal Font)
At this turns ratio the ferrite has to handle 65% of the RF power! It is useful
where the unbalanced feeder's outer may be at a high Z & a choke balun will not
work!
Turns Ratio 10:12 giving a Z ratio of 1:1.44
e.g. 10 turns for 50ê, 12 turns for 72ê Balanced.
ÚÄÄÄÄÄÄÄ¿ ÚÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄo
³ ³10 ³6 0
³ ³Ú¿Ú¿Ú¿ÚŽÚ¿Ú¿Ú¿Ú¿Ú¿ÚÄÄÄ¿
³ ÀÙÀÙÀÙÀÙÀÙÀÙÀÙÀÙÀÙÀÙ ³ 72ê
50ê Txr ³ ß ³ ±±±±±±±±±±±±±±±±±±±± ³ Balanced
Unbalanced ÀÄÂÄÙ ±±±±±±±±±±±±±±±±±±±± ³ Dipole
³ Ú¿Ú¿Ú¿Ú¿Ú¿Ú¿ ³
³ ³ÀÙÀÙÀÙÀÙÀÙÀÄÄÄ)ÄÄÄÄÄÄÄÄÄÄÄo
³ ³6 0 ³
ÀÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÁÄÄÄÄÄÄÄÄÄÄÄÄÄÄÙ
6 bifilair turns + 4 on Amidon T 200-2 TOROID CORE
Make sure the windings are phase & connected correctly.
Why Don't U send an interesting bul?
73 De John, G8MNY @ GB7CIP
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