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Re: Digirig and Z817

 

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The physical size reduction availed by using toroidal versus air core coils in tuners does have its downside!

Knowing the tuner's load tuning range and the approximate antenna load presented to the tuner will go a long way towards preventing such core heating issues - easier for the former, less so for the latter, especially if using some random length of wire on a variety of bands.

Jeff WN1MB



On 12/2/22 11:00, Christopher Maness wrote:

Also, consider a small manual tuner with your FT-817.? I have spent a couple of years using them.? The convenience is nice if you QSY a lot, but they are less efficient than air core coil tuners.? The ferrite can resonate and get hot on certain solutions and waste lots of power.? I have seen this with the SWR drifting with high duty cycle modes.? The drift in SWR is due to the cores heating and changing values.? I have even seen smoke come off the cores when I had the lid off.? I was transmitting under the rated power.

Chris KQ6UP
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