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jpjust
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RF cable length

Thu May 21, 2009 4:58 pm

Hello, folks.

I see some people talking about cutting the RF cable at correct lengths, to avoid standing waves (just as amateur radios do). What do you say about it? Should we really care? Or it doesn't has strong effects in microwaves links?
Joao Paulo Just
RG3.Net and Justsoft
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Blog - jpjust.blogspot.com
 
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Egate
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Re: RF cable length

Sun May 24, 2009 2:31 pm

Think your cable should not even be as long as to have to be cut.
Happy days. :-)
 
doush
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Re: RF cable length

Mon May 25, 2009 12:40 am

mine are 3m each
 
angboontiong
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Re: RF cable length

Mon May 25, 2009 7:37 am

..........................
Last edited by angboontiong on Mon May 25, 2009 10:43 am, edited 1 time in total.
 
ste
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Re: RF cable length

Mon May 25, 2009 8:52 am

You have to tell us the detail as...

1) Distance between radio and antenna.
2) Each end with what type of RF connector.
3) How many RF surge arrester will use.
4) What's type of the RF cable you plan for it.
5) What type of the antenna connector.
6) The antenna gain and distance to other end.

With that, then only we can advice you.
jpjust asks if there are some coax lenght constraints other than the
total signal loss. So something like keep cable at a multiple of wavelength.
I dont feel your questions are correlated with this ;-)

Stefan
 
RK
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Re: RF cable length

Mon May 25, 2009 8:54 am

You have to tell us the detail as...

1) Distance between radio and antenna.
2) Each end with what type of RF connector.
3) How many RF surge arrester will use.
4) What's type of the RF cable you plan for it.
5) What type of the antenna connector.
6) The antenna gain and distance to other end.

With that, then only we can advice you.
Did you even read jpjust's question?
None of what you asked is relevant.
 
RK
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Re: RF cable length

Mon May 25, 2009 8:57 am

Hello, folks.

I see some people talking about cutting the RF cable at correct lengths, to avoid standing waves (just as amateur radios do). What do you say about it? Should we really care? Or it doesn't has strong effects in microwaves links?
I don't know. But what I do know is that wavelength at 5.8 GHz is 5.2 cm.
Cutting cable that exact is difficult.
 
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jpjust
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Re: RF cable length

Mon May 25, 2009 1:50 pm

ste:that's what I meant.

This weekend I learned that cable length does matter. Sometimes, a long cable is better than a short one (but not so long). We have to consider the wavelength and other cable's attributes to determine the best size :)

I'm still learning how to calculate the correct size. I can post it here as soon as I have learned everything correctly.
Joao Paulo Just
RG3.Net and Justsoft
FCP - Furukawa Certified Professional
Blog - jpjust.blogspot.com
 
titius
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Re: RF cable length

Mon May 25, 2009 3:06 pm

Please do so, I cant wait to see results. This is interesting thing if its true.

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