Joe, I have said this several times previously. Put a statement in the contract that payment is to be made upon installation of a system that does not cause you interference. I do this for every appl
Pete, I agree with what Jim said but I would like to add another comment. Any source that is Q5 at one location and unable to be heard at another location 200' away is DEFINITELY close to the Q5 loca
Rick, You are absolutely correct. GFCIs only sense the differential current between the HOT and NEUTRAL lines. Any imbalance greater than ~5mA causes a trip. The current that causes the imbalance can
Amazing! I had heard the signal on 18085.5 for nearly 2 weeks also at amplitudes from nil to S9+10 and within a couple of hours of your posting it vanishes. It is still gone today. Larry, W0QE ______
Just FYI. W0IVJ and I have been tracking down and making measurements on these extremely nasty RF interference sources for the past 17 months. They measure 40dB above the FCC Part 18 limits. Take a l
Pete et. all, For as good as the Samlex 1235 switching power supply is I had an instance where interference from them was heard. Take a look at http://www.w0qe.com/RF_Interference/Samlex_SEC1235%28M%
Be careful with LISNs and preamps. Turning on and off the DUT (device under test) will create significant transients to the receiver. I have never hurt a receiver or spectrum analyzer but have killed
Ditto on the "contract stipulation" requiring no EMI which is a good idea for ALL installations and purchases where objectionable interference may be a possibility. However assuming that fixing the i
Jim, I am very aware of the pin 1 problem and why you would assume that there would be common mode current on the green wire. I also expected that the green wire should pass through the choke but wit
This is rubbish. Measurements I have made at HF show an 8-10dB increase in signal every time the distance is halved for ground wave. Do the math! I have a neighbor with a 2010 Prius and I have follow
Let's do the math for all to see. Assuming a 9dB increase in signal for every halving in distance and using your number of 1800'. Then there would be a 9dB increase in interference @ 900', 18dB @ 450
Also see http://www.lightningsafety.com/nlsi_lhm/IEEE_Guide.pdf for a lightning protection guide from IEEE. Larry, W0QE _______________________________________________ RFI mailing list RFI@contesting
I have made this suggestion numerous times and I will say it again! Be upfront with your HVAC contractor (or anyone you are buying from) and tell them that you demand to not hear any interference fro
Jim and others, I have taken several EMC compliance classes over the years and they always stress that there are 3 main issues that contribute to RFI. They are in no particular order: 1.) Signal rise
Dale, I agree in some instances but the discussion here has been for motors of significant size in appliances. Rise times when driving something such as a motor with a large mass is not that importan
I recently picked up a couple of "outlet" strips that came out of a server farm. These strips are TrippLite PDU-2430 and rack mount with 24 outlets with a 120V 30A cord entering them. The 120V cord w
I have tracked noise and other RF sources for a long time and consider myself competent in this regard. I definitely fall in the camp of recording the noise is not that valuable for several reasons:
Dave, Another great and early EMC guy is Prof. Tom VanDoren PhD. See http://www.emc-education.com/index.php?p=1_6. I took an EMC class from him when he was teaching the class at the University of Mis
100% agreement here. I have posted this numerous times before and to everyone contemplating the purchase of potential interference producing devices WAKE UP and write a REQUIREMENT THAT THE PRODUCT B
Jeff, I am a retired EE and worked for years designing communications equipment for AT&T, medical equipment, and the general aviation industry communications. All the equipment needed to meet various