how likely is a bad Antenna?

FCVPI99

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Rockford,IL
You are not getting conflicting info here. I suspect that some of the YouTube videos are not very clear, or the people making the videos do not understand what they are talking about. Remember, anyone can make a youtube video. Being a ham doesn't imply any sort of expertise or experience, either. It just means they passed a multiple choice test at some point in their life.

Hard to see much in those photos. I wish I was closer and I'd be happy to help you out.
just not enough light .. i had the phone flashlight on AND a hand held flash light ... its just to dark for my camera
 

FCVPI99

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Rockford,IL
To be honest I cannot see the antenna in this one.

In general a discone will give reasonably good performance across a fairly wide frequency range so I would be very surprised if a “one foot” antenna gave better results. I may have missed this but what sorts of frequencies are you looking to receive?

Oh, I don’t think I would suggest grounding the antenna if it’s installed in the attic.

If you are receiving OK with the short cheapie but not with the discone then I would wager money there’s something amiss with the antenna; it may be incorrectly assembled or there may be a problem you can’t see. Did the antenna arrive with the hub assembled?

If the coax is ok (and it sounds like it probably is) then I’m perplexed as to why you’re not receiving anything of note on the discone. Trying to receive a local VHF amateur repeater, or enlisting the assistance of a local radio ham with a VHF handheld might be the way to go…check to see if there’s a club local to you that might be able to help. Generally hams are helpful people and should get you sorted.
ya nothing i can do its about 15 feet from the camera magnet based on that white old computer case its over 80F outside and over 100F in attic ... plus the workout i get trying to get up and around up there and i wasnt going to go hand and knees to get to that Ant again ... i was laid up for 2 days after i put it there .. part of my gimpness is bone problems im sure all my Doctors would just say get the hell out if they new i was doing this stuff ... my will is way way more then my body as for the ground well its on there and im assuming its working i did that cuz someone suggested it might have been a ground issue .. and im trying to do as much as i can at once - as Danny would say .. im getting to old for this Sh...
all i had to do was screw the rods into the core .. just like my old RS discone i got the coax from a place in Texas ... or was it California ... so many orders lately ...it was one of the 2 .. they say they make it to order and test before shipping ... i tested just to be on safe side
 

FCVPI99

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Rockford,IL
Cheap test..get an F Female to UHF Male PL-259 adapter and and f-type to whatever you scanner connector is and try some rg6 between the two.

I purchased some lmr off Amazon, both times I had to re-solder the connectors. I'm DX only, I use rg6 on 8 of 10 of my antennas
made in USA Texas or Cali one of the 2 ... again it tests out fine and they do say they test before they ship .. i cant afford to by more coax ... i have dropped about 600 so far in 2 weeks lol radios ants weather radios light panels for the old 2004/05/06's connectors tools coax ...im sure if i go back il find i got a kitchen sink also...lol
 

JustinWHT

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0 ohms means there is no short as per ever single vid from all the ham guys showing how to test coax on youtube
That's totally incorrect. I guarantee no ham guy will say that.

Zero ohms or close to 1 or 2 ohms is a dead short. You get same reading touching both test leads together. Not a good sign.
An infinite reading means it's open, You get same reading with test leads not touching each other.

Disconnect your antenna. Place test leads on connectors's center pin and shell. It should read infinite. If it reads zero or 1 to 2 ohms, you have a short in the cable or connectors.

Reconnect your antenna. Place test leads on connectors's center pin and shell. It should read infinite. If it reads zero or 1 to 2 ohms, you have a short in the antenna.

While your coax is 52 ohms, that's the RF impedance that can't be measured with an ohm meter.


/edited to comment about your meter photo
In the photo, the needle is on far left indicating infinite resistance. If touch the leads together it will swing all the way to the right to zero ohms or a dead short.
 
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FCVPI99

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Rockford,IL
That's totally incorrect. I guarantee no ham guy will say that.

Zero ohms or close to 1 or 2 ohms is a dead short. You get same reading touching both test leads together. Not a good sign.
An infinite reading means it's open, You get same reading with test leads not touching each other.

Disconnect your antenna. Place test leads on connectors's center pin and shell. It should read infinite. If it reads zero or 1 to 2 ohms, you have a short in the cable or connectors.

Reconnect your antenna. Place test leads on connectors's center pin and shell. It should read infinite. If it reads zero or 1 to 2 ohms, you have a short in the antenna.

While your coax is 52 ohms, that's the RF impedance that can't be measured with an ohm meter.


/edited to comment about your meter photo
In the photo, the needle is on far left indicating infinite resistance. If touch the leads together it will swing all the way to the right to zero ohms or a dead short.
lol... i know how to read my meter :) Discone is down and taken apart and tested again the ant the coax everything test fine no needle movement for short and all a to a and b to b test show 0 but the ant doesnt pic up worth ------ ... i will just switch over to the 4.00 Ant as they work like gain busters ... see what i did there
 

JustinWHT

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While you may know how to read your meter, the advice of....
FCVPI99 said:
0 ohms means there is no short as per ever single vid from all the ham guys showing how to test coax on youtube

Is totally in correct.
 

JustinWHT

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FCVPI99 said:
0 ohms means there is no short as per ever single vid from all the ham guys showing how to test coax on YouTube
They MIGHT be referring to this test....

With nothing connected to far end connector, put ohm meter on near end center pin and shell. Should read open or infinite.

Now short out far end connector with center connected to shell. The near end should read close to zero to maybe ten ohms. THAT might be what they are talking about.
 

John_S

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And to make things more confusing, some ham antennas will show 0 ohms...a dead short. Be careful about knowledge taken from the Tube. It's possible that the small antenna just happens to be tuned near the frequencies you're monitoring. That would make it work better than the discone...even though it's smaller.
 

JustinWHT

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And to make things more confusing, some ham antennas will show 0 ohms...a dead short.
Good point that YouTube viewers may not understand.
Simple dipole will test open.
Folded dipole will test as a short
 
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