I am building a set of feed line common mode chokes to test in my shack, using K9YC's published test data and charts (mahalo, Jim!). Since the chokes will be inserted into existing feed lines, each
Has anyone here read the November article on using the feedline portion of a doublet as a noise antenna for phase cancelling QRM? I am still trying to puzzle out how it might work, and under what con
Thanks for the info on what you are doing Jim, and Davem the offer to share data on your chokes. I am looking forward to studying all of it. If I separate "how many turns and what materials should b
GM - I am looking for a PDF of "Baluns in the Real (and Complex) World" by Frank Witt from the ARRL Antenna Compendium, Volume 5. Interlibrary loan was a no go. If someone has a copy and would be wi
Jamie - Thanks! You can contact me offline either way, k7wxw@qrpdx.org. 73 bill ______________ brevity is beautiful. Jamie WW3S wrote on 11/18/18 9:54 AM: I think I have volume 5, I can try to scan
I am currently in the second (or third) phase of taming the EMI/RFI that plagues my middle-of-the-city-garden-lot-antenna-surrounded-by-RF-sources station. I learned pretty quickly that fixing it was
GA All My noise reduction project continues. I have been working on noise sources in my house but need some help with what seems to be an external source. For data capture, I am using an RSPro2 and R
GE Don, Yes I hear them. They aren't like a SMPS or arcing RF audio which is pretty easy to identify but it is not quite white noise either. I am running the system with the gain turned down and the
First, thanks for the help and suggestions. A number of people thought my laptop might be generating artifacts, so I ran a couple of tests. On the assumption that the laptop was generating the RFI: 1
My RFI battle continues unabated. While I've quieted most of the sources in the house (I still have to figure out how to tame the HVAC system), external noises sources continue to accumulate. There
I've experimented with ethernet-over-power and ethernet-over-cable (MOCA). While I never experienced my RF transmissions causing adapter malfunctions, I did found that some brands of adapters generat
I continue to collect data in my search for RFI sources. The two screenshots, with detail 3 and detail 4, were taken with the house power turned off, from an RSP2 connected to a dell laptop running o
Sorry... I am the gang that can't shoot straight today. Here's the link to the images I mentioned in my last email: https://www.dropbox.com/sh/x6nff71a1iakg7y/AAALpTsfBvUqNXn3u3u0PClXa?dl=0 73 Bill
I did a ferrite bulk order two months ago. I got quotes from Pacific Lodestone, DigiKey, Kreg, Mouse, Newark and Arrow. On the T31 and T43 parts, Arrow was least expensive on all but the 2.4" toroi