DFR- My new view to see if I can hear anything?

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avflyguy

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Did the antenna relocate today. Nearly killed myself getting that dang high on a steep pitch roof! YIKES!

Haven't pulled the cable run yet...still trembling from altitude sickness :) Maybe with new mounting, new cable and connectors, I MAY be able to hear Dallas Fire Rescue again.

Here's some pics of my view....
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Looking SouthEast
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Looking Due East
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Looking North East
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Looking North
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Looking West
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Looking South West

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685 feet MSL (KADS is 644 MSL)

Next is to pull the wire through the attic down 2 stories and down the wall. I'll tackle that Saturday! I'm gonna be REALLY unhappy if my reception doesn't improve drastically!

OH... Here was the old cable and connector - not very pretty!

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Alliance01TX

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Dfr

Howdy

Well as expected the connectors-coax look like the primary culprit on your ability to get DFR. I hope you gave the antenna connector (on the antenna) a proper scrape and cleaning as well....!!

I would pre-test the new coax & connectors, as I had a RS Antenna years ago and had like issues, as the coax did-not 'seal' well, so water / dirt got into the connections at the antenna /coax connetor point. Metal-to-metal issues likely as well.

Once you complete the pre test with new coax, I would hand-tighten (do not use tools) the antenna coax connection and then apply an Liquid Electrical Tape that you can get at most Home Depot, ACE or Lowes Hardware stores in the 'electrical section' of the store. 3M and Star Bright are a couple examples of good liquid tape , and although a bit messy, the stuff works for years and apply very thick and ensure well coated, and takes less than ~30 minute to dry and about a day to fully 'cure'. This will keep the roof trips to a minimum every couiple of years, just to inspect....

Keep us posted.

Thx
 

bhall7

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Cool, thanks for sharing! What kind of ground do you have on your antenna?
 

avflyguy

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Happy to report total success! That 30+ year old lead in cable I was using was the culprit. Problem solved. Hearing stuff now I've not heard in years. My old (but good RS Pro desktop 2022) works like it just came out of the box! Who woudl have thought the antenna wire degredation would have made such a huge difference.

On the grounding - for now I am just using an F connector grounding block alongside with the rest of the Satellite, phone, cable and power grounding rod. I'll finish grounding from the mast to a gas/water line in the attic next time I feel like getting air sick on the roof and filthy in the attic.

In the process I also discovered that my RS Pro97 's BNC connector inside the radio had a break in the wire (a common problem I read about and to my surprise I wasn't the first cowboy at the rodeo to have fixed it)

Happy camper again!!!
 

Russell

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Very cool. With that set up you may be able to hear more and further than you expected. I had a similar setup for years with great results.

Russell
 

Alliance01TX

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DFR Solved!

Great news that the issue is solved....One thing you might reconsider is not using a Gas or Water line-pipe to ground the antenna-mast, but rather stick with the 'Ground Rod' system as that is the best way and safest as well...I little more work but this will also likely improve the signal-to-noise ratio (less noise) for your 'new' set up....

I would not want lightning to traverse a Gas Line....or the water piping either, if you have a option....

Again, good work in trouble-shooting...

Thx

Bill
 

bassman21

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Great news that the issue is solved....One thing you might reconsider is not using a Gas or Water line-pipe to ground the antenna-mast, but rather stick with the 'Ground Rod' system as that is the best way and safest as well...I little more work but this will also likely improve the signal-to-noise ratio (less noise) for your 'new' set up....

I would not want lightning to traverse a Gas Line....or the water piping either, if you have a option....

Again, good work in trouble-shooting...

Thx

Bill
I agree! It wasn't a water pipe, but we had lightning come through the bathtub drain when my CB antenna was mounted to the roof drain vent. This happened back in the 80s when I was a kid and it left the front part of the bathtube all black. Had someone been taking a bath they would have killed.

Also it may not been a good ground as there may be PVC pipe somewhere in the line.
 

avflyguy

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To go from the mast to the side of the house where all the other grounding rod is a run of near 75 feet. I could go down the other side of the house to the gas line pipe that is by the exterior wall shut off valve (all steel pipe) which is a run of about 35 feet. I know it is all steel pipe as the gas co had to run a trace from the meter to the house a few years back as I expanded my driveway and poured concrete over the line. They told me if that line ever went bad, I would be responsible for the cost to bust up the concrete so they could run a new line from the meter to the house if it ever needed to be done.

I guess the other option would be to bang in another grounding rod by the gas line pipe (the shortest route from the mast to earth) and ground the mast that way? How deep and what kind of rod needs to be used? What's the cheapest wire (or best) and what gage should it be? Can it lay on the roof shingles or does it need to be supported by stand-off's away from the shingles/walls?
 

Alliance01TX

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Dfr

Howdy

The other guys can chime in and offer some additional options, but in my view here are the things I would likely do to get the best reasonable grounding. Think safety !

First look at the best (safest) place to hook a bare copper wire to the mast itself, as I cannot tell from the photo's if your mast is on a tripod, house mount or goes to the ground? Thus, you will need to figure out the ground wire mounting & several options (clamps) should be used & recommend putting as much reasonable seperation from any other vents, wires or metal objects on or near to the house.

Make sure however you attach the grounding wire to the mast that it is a clean connection and a solid attachment to the mast to handel any wind or mast movement, etc...Inspect & clean yearly.

Typically I would get size #14 bare copper wire and use that as ground wire (no insulation) to run from the mast to a ground rod. Short runs are always the best runs, if safety is not compromised. I would always run outside and away from any metal if possible....

A 4' copper rod at Home Depot or RS would work fine , just ensure you have the 'clamp' on the rod (it comes with the rod) as some fall off at the store....I would drive the 4' rod at least 1-2' away from the home foundation and not within 4' feet of other ground rods, if possible, to have a 'dedicated' ground.

Some say to use the old TV cable type 'stand-off' (basiscally an Eye-Bolt with wood threads to screw into the wood) to keep the bare-copper-wire 'off' the house but not kknowing your set up, I will let others offer suggestions as I do not have any antenna's mounted near the house, they are all on mast away from the structure.

Hope this helps....

Thx

Bill
 
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I'd recommend doing this to seal up the connector at the antenna:
-First, wrap it up bottom to top with 3M Super 88 electrical tape
-Go over that with a layer of mastic tape, again bottom to top. Home De(s)pot sometimes carries it, but your best bet is a good electrical supply house.
-Go over that with a layer of Scotch-Kote liquid sealant. See above on where to find it.
-And finally, top it off with another layer of Super 88.

On grounding: I'd strongly advise against going to any plumbing inside the house; gas, water, or otherwise. Run it to its own ground rod with #6 green ground wire, with the top of the rod buried 2 feet below ground level per NEC spec. Run that to a ground bus in the attic which your coaxial lightning arrestor should be mounted on, and from there go to the antenna mast itself. You can recycle a neutral bus bar out of an old breaker box for your ground bus. And if you really want to do it right and avoid any potential lightning or static discharge damage to your home electronics, run a buried run of #6 bare from your antenna ground rod around the house to the electrical service ground. Keep in mind that ground potential is the real killer in a lightning strike - if part of your house is at a different ground potential than the rest, lightning will make the jump through whatever path is available.. appliances, house wiring, and so forth.

Since you've already popped the lid on your scanner, why not go ahead and replace the female BNC with a female F connector? If there's a capacitor connected across the connector, get rid of it too. That way you'll have continuous 75-ohm impedance all the way from the antenna to the radio. The antenna is terminated in a SO-239 connector which essentially has no impedance so you're good there.
 
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