G8MNY TECH 07.09.19 06:15l 31 Lines 999 Bytes #365 (0) @ WW
BID : 20570_GB7CIP
Subj: 50Ω - 200Ω HF Balun
Path: OK0NBR F3KT OK0NAG DB0ERF DB0RES DB0EEO DB0GOS ON0AR OZ5BBS CX2SA
N3HYM GB7CIP
Sent: 190907/0904Z @:GB7CIP.#32.GBR.EURO #:20570 [Caterham Surrey GBR]
From: G8MNY@GB7CIP.#32.GBR.EURO
To : TECH@WW

Here is 4:1 balun for HF freq`s (New Mar 05)
(8 Bit ASCII graphics use code page 437 or 850, Terminal Font)
At this ratio the ferrite only has to handle 50% of the RF power!

Turns Ratio 10:20 giving a Z ratio of 1:4

e.g. 10 turns for 50Ω, 20 turns for 200Ω Balanced.

┌───────┬────────────────────────────o
│ │10 0
│ │┌┐┌┐┌┐┌┐┌┐┌┐┌┐┌┐┌┐┌───┐
│ └┘└┘└┘└┘└┘└┘└┘└┘└┘└┘ │ 200Ω
50Ω Txr │ ▀ │ ▒▒▒▒▒▒▒▒▒▒▒▒▒▒▒▒▒▒▒▒ │
Unbalanced └─┬─┘ ▒▒▒▒▒▒▒▒▒▒▒▒▒▒▒▒▒▒▒▒ │ Balanced
│ ┌┐┌┐┌┐┌┐┌┐┌┐┌┐┌┐┌┐┌┐ │
│ │└┘└┘└┘└┘└┘└┘└┘└┘└┘└───)─────o
│ │10 0 │
└───────┴──────────────────────┘

10 bifilair turns on a Amidon T 200-2 TOROID CORE. Make sure they are phase & connected correctly.


Why Don't U send an interesting bul?


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