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Old 26th Nov 2017, 3:12 pm   #3
Argus25
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Join Date: Oct 2016
Location: Maroochydore, Queensland, Australia.
Posts: 2,679
Default Re: Directional coupler DC - 300 Mhz

Hi Wendy,

If you want to make a wide band largely frequency insensitive directional coupler that works well at VHF and above, its simple to avoid transformers and cores and simply use a short length of coax with some wires added into it, I used the thin teflon coated wire wrap style wire. Its just a matter of bunching up the braid and threading it through.

I've attached an article on a VHF directional Watt meter I designed once (when my callsign was ZL1WWV..always on time) using this method, probably the directional coupler design will be readable. I can't vouch for its low frequency performance, it probably would require more coax.

Anyhow, this method is something to consider when designing a directional coupler.

(If the images are not readable I could convert them to a pdf file and attach that)

Hugo
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Last edited by Argus25; 26th Nov 2017 at 3:18 pm.
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