reconrider8
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what would be a good coax to run for just a vhf uhf antenna "sputnik" thats going to be around a 55 foot run?
vhf/uhf coax run
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Quad shield RG-6. And that will open the thread for others to tell us how bad or good is that suggestion.
Quad shield RG-6. And that will open the thread for others to tell us how bad or good is that suggestion.
If it will only be used for listening, not transmitting, then RG-6 is one alternative. If transmitting is ever done, then the impedance mismatch is going to make RG-6 a bad option. Transmitters are more 'picky' than receivers. There's still an impedance mismatch when receiving but it's not as apparent.
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reconrider8
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So rg6 qs would be a good run im also putting up an 800mhz antenna running lmr400 at the same length will that be fairly good?
reconrider8
Member
for the 800 mhz right?
mmckenna
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At 800MHz, your RG-6 will have about 4.8dB of loss.
At 800MHz, LMR-400 will have about 2dB of loss.
The 2.8dB difference in loss is equal to almost half the received signal strength.
Just for giggles, 800MHz at 55 feet:
LMR-600 will be 1.3dB of loss
1/2" Heliax will be 1.08dB of loss.
LMR-400 is a lot easier to work with than LMR600 or Heliax. You can install UHF connectors your self on LMR400 pretty easy. It is flexible enough that it's easy to work with. The larger cables get awkward and unless you have the correct tools, it'll be difficult to install the connectors properly. For the little bit of signal you'd gain, you'd spend a lot more money. LMR400 is a good compromise in these sorts of situations.
At 800MHz, LMR-400 will have about 2dB of loss.
The 2.8dB difference in loss is equal to almost half the received signal strength.
Just for giggles, 800MHz at 55 feet:
LMR-600 will be 1.3dB of loss
1/2" Heliax will be 1.08dB of loss.
LMR-400 is a lot easier to work with than LMR600 or Heliax. You can install UHF connectors your self on LMR400 pretty easy. It is flexible enough that it's easy to work with. The larger cables get awkward and unless you have the correct tools, it'll be difficult to install the connectors properly. For the little bit of signal you'd gain, you'd spend a lot more money. LMR400 is a good compromise in these sorts of situations.
reconrider8
Member
So i would still have a 1 deb gain
w2xq
Mentor
You'll never hear the difference of 1dB.
mmckenna
I ♥ Ø
Exactly, and you'd spend a lot more money and put a lot more work into it for something you likely wouldn't be able to notice.
Sometimes good enough is good enough. There will always be something "better", but in the end if you got the signal, you got the signal.
Good engineering doesn't mean overdoing everything in the hopes of making it work, but doing it right, reasonably priced and a workable solution.
Ya' done good.
Sometimes good enough is good enough. There will always be something "better", but in the end if you got the signal, you got the signal.
Good engineering doesn't mean overdoing everything in the hopes of making it work, but doing it right, reasonably priced and a workable solution.
Ya' done good.
reconrider8
Member
Yea i got a lariad 3db gain omni 800mhz antenna but i was just hoping that the 400 would be good enough and i was wanting to see what would a good deal for the coax for the 150/450
mmckenna
I ♥ Ø
As you go down in frequency, your coaxial losses will also go down. So the losses for the same run of coaxial cable in the VHF and UHF ranges will be less than at 800MHz.
reconrider8
Member
what is a good set of coax (lmr400) tools something thats easy and isnt all that expensive i like the ones the cable man has thats like 10 sec to prep the line and put another connector on it
mmckenna
I ♥ Ø
LMR 400 will accept the standard RG8 sized UHF male connectors. You would need to solder them on. If you want to do something other than UHF, you'd likely need a crimp set.
I've got a $99 set I bought somewhere that does RG-174 up through LMR-400. It's good enough for my occasional use. If I was doing installs full time, I'd want the better stuff. I do have the high end grade stripper and crimping tools at work, and they are really nice, but they were expensive.
As for the low end Chinese made tools and the high end commercial ones, the price difference is huge, on the order of a few hundred bucks. I do occasionally screw up a crimp connector with my cheap tools, but I can screw up a lot of $3 connectors and still come up cheaper than the high end tools. In my case, I can always bring my work crimp tools home if I need to. So don't get to hung up on the quality level. Just keep a few extra crimp connectors on hand.
I've got a $99 set I bought somewhere that does RG-174 up through LMR-400. It's good enough for my occasional use. If I was doing installs full time, I'd want the better stuff. I do have the high end grade stripper and crimping tools at work, and they are really nice, but they were expensive.
As for the low end Chinese made tools and the high end commercial ones, the price difference is huge, on the order of a few hundred bucks. I do occasionally screw up a crimp connector with my cheap tools, but I can screw up a lot of $3 connectors and still come up cheaper than the high end tools. In my case, I can always bring my work crimp tools home if I need to. So don't get to hung up on the quality level. Just keep a few extra crimp connectors on hand.
reconrider8
Member
I just want an easy to use and low cost set for my occasional use but i want something that will hold up
Fast (easy), cheap, good (durable). As with most things in life you get to pick two of those qualities.
reconrider8
Member
yea i understand that lol
For premium installation. Low noise low loss.
Uhf frequencies attenuate quickly down a typical coax line. Hard line is the best but needs special tools for connections. Great for long runs up a 300ft tower. For home use. Best cable for very low loss would be a premium low loss 50 ohm trans impedance cable. Highly recommend Times Microwave CA600 Coax if budged permits. Times Microwave ca400 very good second best choice. With CA600 Signal would have 3x gain over standard Rg 8/u and 1.5x over RG213. Rg9913 also very low loss but best for in doors. Weathers badly soaks up water. You will get maximum signal to radio over broad band up to 1ghz. Also excellent for transmitting. .For typical installation rg59 is very respectable for reception only.
Uhf frequencies attenuate quickly down a typical coax line. Hard line is the best but needs special tools for connections. Great for long runs up a 300ft tower. For home use. Best cable for very low loss would be a premium low loss 50 ohm trans impedance cable. Highly recommend Times Microwave CA600 Coax if budged permits. Times Microwave ca400 very good second best choice. With CA600 Signal would have 3x gain over standard Rg 8/u and 1.5x over RG213. Rg9913 also very low loss but best for in doors. Weathers badly soaks up water. You will get maximum signal to radio over broad band up to 1ghz. Also excellent for transmitting. .For typical installation rg59 is very respectable for reception only.
WA0CBW
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Along with using good coax it is equally important to weather proof the connectors as stated above. Without weather proofing most coax will deteriorate very quickly. Water will migrate into the coax increasing its signal loss. Failure to properly weather proof the connector and coax can cause catastrophic failure after a single rain storm. Spend a few bucks more and get the correct tape and follow the connector/coax weather proofing instructions.
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