rfi

on my roof are 4 antenna... a 4010 EFHW and a 10m/6m/2m/70cm vertical, attached to my IC7100 a dual band 2m/70cm, attached to my FTM400. and a tram 1411 discone for my Pro197 they are all at least 8ft apart. the base of the discone mast is a few feet lower on the roof than the rest which...

I have attached 3 images of my RFI problem Image 1: Shows the RFI morphing into the alternating signal. This happens every 2.5 min and starts from a constant signal to a stronger signal for 5 sec then into the alternating signal for 5 sec. Image 2: shows spacing of RFI Image 3: What my...

I’m about to tackle a clean-up operation on the computer leads – USB, video, etc. I can see that I have interference from the computer right from hf through to a few hundred MHz. I see that the ferrite materials in the clip-ons are designed to peak at specific frequency ranges. The computer...

I picked up a used 400W HF amp. I dropped it into my system between my multi-band 80m OCF dipole and my 100W HF radio. My dipole passes overhead the shack about 20' above me and my gear. Prior to getting the amp I had no trouble in the shack running barefoot. The EMP calculations (assuming...

Hello, I am doing an engineering project that requires the approximate radio-frequency interference ranges (or spectrum) given off by typical power line insulators used by utility companies. I want to know what the spectrum is and who it affects. One would think this information is readily...

Has anyone else had problems with RFI from cheap Chinese goods? I'm currently having issues with an "Auto-VOX A118 B40" car dash cam which is destroying 2M ham/business bands within 20-30 feet of my car. A ferrite choke reduced noise to about S2 on all but one frequency (148.510 per my...

Found this lately on my waterfall on SDRSharp. Was wondering if anyone out there may have come across it in the past. Its from 143.945Mhz-145.067.

Hi all, Another Noob Here, I am studying for my Tech level Ham, in the mean time I'm working on a receive issue in Sauk County near Baraboo. I have three problems that I am facing just on reception. T.V. Free broadcast Digital Wireless Internet all Scannable frequencies in my kitchen as well...

Well, I woke up to this crud on the radio this morning :-( The strongest being centered around 7.4 mhz. I ruled out anything local to my house by killing the main breaker, the RFI was still there. Note the "DNA" pattern in the first image - anyone recognize it? It sounds like constant...

After getting the shack set up in the new house, I noticed i can pick up the analog cable tv transmissions over the air. From my research I've found its unwanted transmision from a fauly coax somewhere in the cable providers system and a small degree is allowen by the FCC. But I'm receiving it...