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Author Topic: Isolator Frequency Range  (Read 1472 times)

Offline bandarr3000

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Isolator Frequency Range
« on: August 16, 2019, 2005 UTC »
OK, stupid question time. If I have an 1.8-30MHz isolator on my multiband antenna (80m-6m), should I still be able to transmit 6m?
« Last Edit: August 16, 2019, 2009 UTC by bandarr3000 »
Yaesu FTDX3000D
SDRPlay RSP1A
W6LVP loop antenna
EFHW 40-10 as inverted L
Grand Rapids, MI

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Offline Josh

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Re: Isolator Frequency Range
« Reply #1 on: August 16, 2019, 2138 UTC »
If you're talking about a line isolator and not a lowpass filter, yes. If you had a lowpass filter with a cutoff above 6m yes in that case too. If you had a lowpass filter below 6m cutoff obviously no.
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Offline bandarr3000

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Re: Isolator Frequency Range
« Reply #2 on: August 20, 2019, 0332 UTC »
If you're talking about a line isolator and not a lowpass filter, yes. If you had a lowpass filter with a cutoff above 6m yes in that case too. If you had a lowpass filter below 6m cutoff obviously no.

Thank you!
Yaesu FTDX3000D
SDRPlay RSP1A
W6LVP loop antenna
EFHW 40-10 as inverted L
Grand Rapids, MI

eQSL please to bandarr@gmail.com

Offline Josh

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Re: Isolator Frequency Range
« Reply #3 on: August 20, 2019, 1714 UTC »
More to the point, isolators simply choke off the rf flowing on the outside of the coax and have no effect on whatever rf is flowing inside that coax. Isolators are also often frequency dependent insofar as their maximum effectiveness goes.
Some that work spectacularly at hf fail at vhf and above, those mixed for best response at vhf and above are seldom useful at hf. I've mixed isolator ferrites for a broader response, for example, using 43 mix as well as type 6 and/or type 4.
« Last Edit: August 20, 2019, 1717 UTC by Josh »
Conveniently located near Vincennes Indiana.