[Elecraft] Quiet Ductless HVAC System

[Rick Bates, NK7I]

Just as other appliances sold these days with a motor i.e. washing 
machines, dishwashers...  while digital control may add nice features, 
the noise generated can reduce operator pleasure (or operating hours).

Getting any manufacturer to routinely add filtering (even if under $1), 
won't happen without a lot of customer noise in return.  ;-)

Rick NK7I

On 5/27/2020 10:17 AM, Dave Cole wrote:
> Of late, the fans in these systems are speed controlled by PWM.  Nice 
> high power square waves...
>
> 73, and thanks,
> Dave (NK7Z)
> https://www.nk7z.net
> ARRL Volunteer Examiner
> ARRL Technical Specialist
> ARRL Asst. Director, NW Division, Technical Resources
>
> On 5/27/20 10:08 AM, Phil Hystad wrote:
>> I didn’t know that an HVAC system would be an RFI generator.  What 
>> part of HVAC is the cause of this and is this a recent problem in 
>> manufacturing units?
>>
>> Note — I have never lived in a home with AC — never had a need here 
>> in the northwest (Seattle area).  I probably should add that when we 
>> go to our condo on Kauai the first thing my wife does is to turn off 
>> the AC unit.
>>
>> 73, phil, K7PEH
>>
> ______________________________________________________________
> Elecraft mailing list
> Home: http://mailman.qth.net/mailman/listinfo/elecraft
> Help: http://mailman.qth.net/mmfaq.htm
> Post: mailto:Elecraft at mailman.qth.net
>
> This list hosted by: http://www.qsl.net
> Please help support this email list: http://www.qsl.net/donate.html
> Message delivered to rick.nk7i at gmail.com