[Elecraft] K3S "HI-RFI" warning a bit too sensitive?

[Michael Walker]

I had this problem once.  Next time I showed up with a recording of
everything they said over dinner and told them I recordered it over a block
away.

That got it fixed.

In another case, with 49Mhz headphones, I just bought them a new 900mhz
pair and gave it to them if they gave me their old ones.  Sometimes it is
just cheaper.

Mike va3mw

On Fri, Jun 17, 2016 at 11:23 AM, Joe Subich, W4TV <lists at subich.com> wrote:

>
> Using a VHF capable SDR in wideband mode, I found a strong FM signal
>> on 49.850 and traced it to...
>>
>
> The SDR should be capable of providing a calibrated (dBm) signal
> strength.  With that information and the distance from the target
> it should be relatively simple to calculate the ERP of the baby
> monitor.
>
> Given that you report the "HI-RFI" indicator is being activated on the
> K3S, I would suspect the baby monitor is producing an illegal ERP -
> whether it is out of spec accidentally (manufacturing) or has been
> tampered with by the owner is not an issue.  I would generate a letter
> of complaint to the FCC (with calculated ERP data) indicating that you
> believe the baby monitor is not in compliance with regulations and must
> cease.  Send a copy to the owners of the baby monitor a week before
> mailing the complaint to the Commission.
>
> 73,
>
>   ... Joe, W4TV
>
>
>
>
> I believe the manual states that it takes a watt or two of power at the
>> antenna connector to set off the HI-RFI warning. Imagine my surprise when
>> I
>> began seeing the warning on my brand new K3S just days after I'd assembled
>> it. Almost everyone else who has seen this error has been using a K3 in a
>> contest environment with multiple transmitters, so I was particularly
>> stumped as there are no other transmitters in my shack (everything is
>> boxed) and no active hams in my neighborhood. I did some testing and
>> traced
>> it to a signal coming in on my 6 meter antenna, which when I disconnected
>> it caused the HI-RFI warning to go away. Using a VHF capable SDR in
>> wideband mode, I found a strong FM signal on 49.850 and traced it to...
>>
>> A baby monitor. Yep, not one block from my house lives a couple with a
>> cheap 49MHz baby monitor blasting away on 49.850MHz all hours of the day
>> and night. A short "fox hunt" with a service monitor confirmed this. There
>> is 100KHz worth of splatter coming from this thing and my old Icom 706
>> shows it as S9 with the attenuator on (and S9 +60 without). I spoke with
>> someone at the house and confirmed that this was the problem by shutting
>> down the device for an hour. Unfortunately, the couple's mother-in-law
>> lives with them and insists on using the baby monitor all day and night.
>>
>> I will continue to press for a diplomatic solution (possibly offering to
>> buy them a newer 800/900MHz unit), but should I fail at that, is this
>> something I should worry about as far as damaging my K3S? I find it hard
>> to
>> believe that a baby monitor is pumping out more than 1 watt, so I'm
>> inclined to believe that the K3S is being a bit overprotective. This plus
>> the fact that my 6 meter antenna is a PAR Omniangle which is
>> omnidirectional and according to PAR has no appreciable gain. I'm tempted
>> to program the K3S to ignore the HI-RFI warning for the time being.
>> Thoughts?
>>
>> Chris
>> KB9SDX
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