Dave: For some reason, a lot of animals like to chew on or eat PVC. That is why cats chew on line cords. I had a run of RG213 on the ground in my suburban yard, Squirrels chewed through it 3 times in 5 years. I replaced it with a polyethylene jacket cable, and its been left alone for 7 years so far. I know Polyethylene is critter resistant, not sure about other polyolefins. Check out RG-6 made for direct burial. Many have a polyethylene jacket. You might also try putting some voltage on the shield to ground. Once the critter breaks through the jacket, he'll find a surprise inside. Not too much -- just enough to supply a few milliamperes. --Mike, WV2ZOW
On Mon, Nov 9, 2015 at 2:38 PM, Dave Olean <[email protected]> wrote: > I was transmitting on 160 last week, and after calling a CQ I noted that > the background noise from one of my beverages dropped to almost nothing. > Something obviously broke right then. All checks pointed to something > external to the shack. I finally got out in the woods and checked the > antenna system. All looked great. I used my new SARK-110 vector network > analyzer and saw very believable results when connected to my 1100 ft long > Europe beverage: about 75 ohms impedance and a VSWR that fluctuated between > 1.5 and maybe 1.8:1 across the freq range. I double checked the entire > beverage run for shorts or anomalies, and even took apart the termination > box to make sure all was OK. The last thing left was the 1000 ft run of > flooded RG-6 coax. I had run the cable on the ground back to the house > about 2 years ago. It was mostly invisible now, being covered with leaves > and moss etc etc. A TDR check showed gross "bad" things and a VOM test > across the center pin to ground showed a resista > nce of 35 ohms while the far end was terminated in a 75 ohm load. > Obviously the cable was compromised. I made a quick inspection and found a > few spots where small animals had chewed on the coax enough to break > through the outer plastic covering and into the braid and aluminum foil > shield. Water and gunk have caused a low resistance between center pin and > the shield. > What are my options now? I don't want to spend another $150 for > another roll of coax just so a squirrel can feast on the PVC. Should I > route the coax in the air and away from small mouths? That is one option. > It seems that digging a 1000 ft trench thru the woods and burying it would > work, but it would be an awful big chore for a 70 year old doofus. I doubt > that I could manage that. If I run the coax above ground, I run the risk of > picking up noise etc. I also worry about falling limbs and old dead trees > falling on it. With a few beverages in the woods, I can't afford to spend > $150 each time an animal feasts on it. I need to do something different! > Incidentally, the beverage still has great directivity, but signals > are very weak with the bad cable. It is barely useable now as a result. > 73 > Dave K1WHS > > _________________ > Topband Reflector Archives - http://www.contesting.com/_topband > _________________ Topband Reflector Archives - http://www.contesting.com/_topband
