[RFI] Solar Power RFI

Cortland Richmond ka5s at earthlink.net
Sun Jan 31 00:43:41 EST 2016

On 1/30/2016 12:35 PM, Michael St. Angelo wrote:
> FCC compliance does not eliminate all RFI, it sets maximum limits for
> various frequency ranges. Even if it compliant it may interfere in some weak
> signal conditions.

Even if a device using or generating RF meets Part 15 limits (its 
unlawful to sell otherwise) it can still cause harmful interference -- 
which makes it illegal for us to turn it on/(see § 15.15 General 
technical requirements./, below).  States that enforce implied warranty 
place the burden on sellers; that's why they like to disavow any implied 
warranty of suitability. See for example the Michigan law on THAT at 

Note that I am not an attorney and this isn't legal advice.

And here's where we violate FCC rules by turning it on:

/§ 15.15 General technical requirements./

/(a) An intentional or unintentional radiator shall be constructed in 
accordance with good engineering design and manufacturing practice. 
Emanations from the device shall be suppressed as much as practicable, 
but in no case shall the emanations exceed the levels specified in these 
rules. /

/(b) An intentional or unintentional radiator must be constructed such 
that the adjustments of any control that is readily accessible by or 
intended to be accessible to the user will not cause operation of the 
device in violation of the regulations. /

/(c) Parties responsible for equipment compliance should note that the 
limits specified in this part will not prevent harmful interference 
under all circumstances. Since *the operators of part 15 devices are 
required to cease operation should harmful interference occur to 
authorized users of the radio frequency spectrum*, the parties 
responsible for equipment compliance are encouraged to employ the 
minimum field strength necessary for communications, to provide greater 
attenuation of unwanted emissions than required by these regulations, 
and to advise the user as to how to resolve harmful interference problem 
(for example, see § 15.105(b))./

emphasis added

Cortland Richmond

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