[Elecraft] P3 Noise signature

[David Christ]

I don't know if RFI is inversely related to price or not but my Precor unit is RFI free.  If I were to go shopping for a new one I would take my K3 along and see what happens when the proposed new treadmill is running.  

This approach is much harder for TV because there are always so many on at the same time at the store.  Wish there was a registry of makes and models of any kind of appliance listing whether they caused RFI or not.  We hear occasional anecdotal reports but these are nowhere collected.

David K0LUM


On Apr 30, 2013, at 10:16 AM, Dave Van Wallaghen wrote:

> Interesting. I have an older treadmill here (15 years+) but have not seen that type of RFI. The bad news is that it needs to be replaced and I'll probably have this issue with a new one.
> 
> Good news is though that I can't work out and operate at the same time. And the tv is usually not on if I'm in the shack unless the wife is home at the same time. Usually not very often though.
> 
> Amazing the sources of RFI these days. I'm still hanging on to most of my 15+ year old appliances just to stay away from newer RFI generators. But like you said, they can radiate over some long distances so I'm sure I'll hear my neighbors stuff like Fred.
> 
> Looks like I might have to pour over Jim, K9YC's RFI doc again ;-)
> 
> 73,
> Dave W8FGU
> 
> 
> 
> On 04/30/2013 11:03 AM, Phil Hystad wrote:
>> RFI...
>> 
>> I have a very pronounced noise on my K3 (and, my Icom Pro III too) on the 80 meter band and it has peaks about 20KHz apart.  Very broad (P3 wave form about 6000 Hz wide and it has slightly bell-shape) and very distinctive in the noise sound you hear on SSB audio.
>> 
>> I know the source though -- it is my wife on the treadmill.  You can almost see and hear the motors and treadmill belt moving by the subtle pulsating of this RFI on the K3 and P3.  It is strong too -- peaks at about 40/9.  And, as an experiment, I got into my truck with my mobile rig (Icom 706) and drove off.  I was a quarter of a mile away by the time the signal strength dropped to a level that I could not hear it anymore.  So, if this is the kind of thing bothering you it does not need to be close.
>> 
>> The good news is that we both prefer going to LA|Fitness rather than work out in our little home gym so this is no longer a big issue but it still happens maybe a few times a month when my wife chooses to work out here.  But, usually that is when I am at work or not on 80 meters which is almost always at night.
>> 
>> 73, phil, K7PEH
>> 
>> 
>> On Apr 30, 2013, at 7:29 AM, Dave Van Wallaghen <w8fgu at comcast.net> wrote: