Herb --
I don't have Beverages, but rather pennant antennas. I think we have potential problems at both ends of the feedline and need protection at both ends. I use Fair-Rite 31-material snap-on cores at both ends, and there's a noticeable difference in the noise level if I remove either one. I suggest you check out "A Ham's Guide to RFI, Ferrites, Baluns, and Audio Interfacing," by Jim Brown, K9YC, which can be found at http://www.k9yc.com/RFI-Ham.pdf. I found it very helpful in understanding that problem and others, and have been able to do a lot to reduce the amount of locally-generated noise that finds its way into the shack. Hope this helps. Art Delibert KB3FJO ________________________________ From: Topband <[email protected]> on behalf of Herbert Schoenbohm <[email protected]> Sent: Thursday, December 1, 2016 12:06 PM To: Topband Subject: Topband: Beverage Feed-line Noise Pickup On my Beverage feed-line RG6 runs (some 200 feet) I use multi-turns a large toroid on each feed-line and the attach each coax to a grounding block and good ground rods (typical Hume Depot RG-6 variety) then on the other side of the grounding block before the coax runs about 20 feet to the Beverage Switch I have another large wound 13 turn toroid. I have since learned that I probably have all my feed-line noise suppression stuff in the wrong place and that the equipment side toroids are probably useless anyway. Now I am told that this noise pickup suppression stuff needs to be out by the actual Beverage feed and about 20-30 feet away. The reasoning is that the noise pickup by the feed-line needs to be blocked from coupling into the antenna itself. Is this true? I am starting to move the toroid-ground-toriod RG-6 "T" combos out closer to the antennas. I noticed that DX-Engineering sells an RFCC-1 box designed for Beverage coax runs but suggests it be place about 20 to 30' from the Beverage feed which has it's own separate ground rod. I bought one and before I put it out near the Beverage feed I thought I would it in place of the toroid system near the shack on one of the Beverage feedlines. However when I grounded the unit to the Beverage ground system near the shack I immediately noticed the noise floor jump up by about 10 db. I now know it is in the wrong place but this test with the DXE RFCC-1 may prove something of interest. Please correct my assumption if it is wrong: Noise pickup from long Beverage feed-lines flows back toward the Beverage feed point and then it is coupled via the feed point transformer back down the center conductor to the receiver. If this is true I will remove all toroids at the house and put them out near Beverage feed points (about 30 feet away with separate grounds based on the advice I receive back from this post. Please let me know what you think about this. Herb Schoenbohm. KV4FZ _________________ Topband Reflector Archives - http://www.contesting.com/_topband Topband Archives - Contesting Online Home<http://www.contesting.com/_topband> www.contesting.com Topband Mailing List Archives. Search String: [How to search] Display: ... _________________ Topband Reflector Archives - http://www.contesting.com/_topband
