I took my meter out to the antenna, I hooked it up with 1 foot jumper. I calibrated meter and checked power and SWR. SWR went up to 1.25 from 1.1 the power went from 4 watts to 3 watts. Hmm is that normal or is that a ton. 25 percent power loss. I am just on 11 meters, and did check the forum before I posted on this issue, Damn I don't want to be redundant ! I bypassed my amp and checked and had the same readings, so I am out of my clueless thoughts. I hope everyone is OK during this SHI# we are all going through, and I apologize in advance if this is a dumb question however some are bored and cant wait to lend a hand. Thanks gentleman you guys are the best,,,,,,,,,,,,,,,,,M.M.
-
You can now help support WorldwideDX when you shop on Amazon at no additional cost to you! Simply follow this Shop on Amazon link first and a portion of any purchase is sent to WorldwideDX to help with site costs.
Power loss at antenna ?
- Thread starter Mark Malcomb
- Start date
it shows that your previous tests @ the radio end were affected by your lossy coax/inline amp/ect.
the SWR meter won't "see" anything before it
the SWR meter won't "see" anything before it
I changed my coax on my base antenna and wow what a difference...
I guess that is a big problem, I have 130 ish feet of new coax which I really don't know the quality of TRAM 8X-B, I was surprised that my SWR at the radio went down from 1.75 to barley a movement after putting it in. I posted this and got a lot of opinions on this a few months ago, wow it maid my head spin, yes all of this is a bit Greek to me but I'm trying to figure it out. Thanks for your reply, I am using a new Gain Master if that info helps at all.
BJ radionut
Supporting Member and 6m addict
http://kv5r.com/ham-radio/coax-loss-calculator/
If your feedline not listed use the BELDEN Equiv.
Good reference calculator for the feedline.
When using the ERP calculator for antenna gain:
Dipole or 1/4 wave ground plane = 0
Folded Dipole = 1.25 (close spaced Quad loop)
1/2 wave GP = 1.5
5/8 wave GP = 2
Single full size Quad loop = 2.8
2 element beam = 5 (more like 4.5 unless truly optimized) Ex: Moxon/Hex Beam etc.
3 element beam = 6
4 element beam = 7
These are pretty close dBd numbers, do not use (dBi).
Manufacturers numbers 99% time those mean squat unless they supply Test Range measurements...(which most do not)
Also NOT modeling software numbers neither, in most cases can be arbitrary also by what are the modeling parameters.
If your feedline not listed use the BELDEN Equiv.
Good reference calculator for the feedline.
When using the ERP calculator for antenna gain:
Dipole or 1/4 wave ground plane = 0
Folded Dipole = 1.25 (close spaced Quad loop)
1/2 wave GP = 1.5
5/8 wave GP = 2
Single full size Quad loop = 2.8
2 element beam = 5 (more like 4.5 unless truly optimized) Ex: Moxon/Hex Beam etc.
3 element beam = 6
4 element beam = 7
These are pretty close dBd numbers, do not use (dBi).
Manufacturers numbers 99% time those mean squat unless they supply Test Range measurements...(which most do not)
Also NOT modeling software numbers neither, in most cases can be arbitrary also by what are the modeling parameters.
searched for a manufacturers data sheet and all I could find is a chart for it at !00 MHz, 200 MHx, 400 MHz,ect.................
nothing for the lower bands.
RG-8X-B Coaxial Cable Specifications:
Attenuation
Frequency
MHz Attenuation
dB/100 ft. Attenuation
dB/100 m
100 4.05 13.30
200 5.79 19.00
400 8.38 27.50
700 11.43 37.50
900 13.11 43.00
Wow thanks for all the information which will take 10 beers to compute, It looks like the new coax I purchased, which I did read as many reviews on this brand as I could find, were all good. They were probably plant reviews from the manufacture. Just throw money at it until it works! Kind of sounds like my wife 
Thanks to everyone I will look into 150 feet of Belden coax. Skip did roll in yesterday and said hello to Hawaii, and Australia. Can't wait to here the difference with good coax. Hats off to you guys..MM
Thanks to everyone I will look into 150 feet of Belden coax. Skip did roll in yesterday and said hello to Hawaii, and Australia. Can't wait to here the difference with good coax. Hats off to you guys..MM
At those lengths (130 feet) you need to upgrade to the LMR400 types or similar. Remember you will see a lower SWR at the radio as you will see the same return loss as you see in the forward loss.
If you change out the coax and your SWR goes up and you don't like it, put the old coax back on it.
The lowest SWR makes me feel better.
The lowest SWR makes me feel better.