[RFI] Solar panel RFI

[Dave (NK7Z)]

Jim,

As always, thanks for the data here!

73, and thanks,
Dave (NK7Z)
https://www.nk7z.net
ARRL Volunteer Examiner
ARRL Technical Specialist, RFI
ARRL Asst. Director, NW Division, Technical Resources

On 2/20/22 16:31, Jim Brown wrote:
> On 2/20/2022 2:48 PM, Dave (NK7Z) wrote:
>> That is most interesting material, thank you!  Will you all be 
>> including a test fixture description as well?
> 
> Yes. One of several jigs I use is a BNC to Pomona male adapter with 
> alligator clips fitting over over the male pins. I use it at the end of 
> a suitable piece of RG400, and dangle it off the arm of a chair. For 
> calibration, I use a piece of #10 copper, folded over and covered with 
> solder as a short, a 1% large format 49.9 ohm chip resistor. To verify 
> calibration at high frequency, I use a similar chip resistor, 5K or more.
> 
> I don't trust this jig for precision much above 10-15 MHz, but it's 
> plenty good for this purpose.
> 
> I can get repeatable results measuring a single turn (one pass through 
> the core) for everything I've tested with the exception of #61, which 
> comes nowhere near data sheet values for ui for a half dozen cores I've 
> measured. This one must be identified by its extremely narrow resonance 
> at HF.
> 
> As of a few days ago, Ward had sent it to layout, along with printouts 
> of VNWA log impedance sweeps of the 12 and 16 turns through the six 
> mixes of Fair-Rite 2.4-in o.d. toroids in my stash -- #31, 43, 52, 61, 
> 75, and 78.
> 
> 73, Jim K9YC
> 
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