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RG58 vs RG59

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STA...@yalevm.ycc.yale.edu

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Jan 19, 1992, 2:00:23 PM1/19/92
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I need to make a fairly long run of coax cable from an RF distribution
amplifier - and I was wondering what problems I could encounter if I used
RG58 instead of the standard RG59.... would the difference of the RG58's
50ohm impedence as compared to the RG59's 75ohm make a big difference in
signal quality, strength, loss over distance, etc. etc.?

Bill Pfeiffer

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Jan 20, 1992, 1:14:34 AM1/20/92
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The 58 is the '50ohm equivilent of rg 59. There is a thicker 75ohm cable
out there (possible rg-9) that cable systems use for runs to multi-unit
dwellings, but it's expensive and if your run is less than 200' don't
bother. If it is more, you probably still will have plenty of signal
left with the rg-59. The rg-58 will cause impedence mismatches and swr
problems which might cause ghosting and other problems, besides, the '58
is no better in the loss dept.

If your signal is ok at the beginning of the run, dont amplify it there.
The amp might get overdriven. Also, if you are conducting CATV signals,
make sure any amp you use is set up for 'cable tv slope'. If you must
use splitters, try to get one splitter with enough taps for all your
receivers, or use a 'feed thru' tap rather than multiple splitters.
Splitters can have anywhere from 2-5 db loss (some older ones have more)
at VHF and cable frequencies.

Good luck.

Gary Sanders

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Jan 20, 1992, 6:57:38 AM1/20/92
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In article <92019.504...@YaleVM.YCC.Yale.Edu> STA...@YaleVM.YCC.Yale.Edu writes:

Yes you would notice the differance with rg58.. If you need to make a
long run use RG6. It is 75ohms and is good for runs upto ~200ft. You should
make sure you have a good amp on both ends of the line if possible..

--
Gary W. Sanders (gws@n8emr or ...!osu-cis!n8emr!gws), 72277,1325
N8EMR @ N8JVY (ip addr) 44.70.0.1 [Ohio AMPR address coordinator]
HAM BBS 614-895-2553 (1200/2400/V.32/PEP)
Voice: 614-895-2552 (eves/weekends)

Pete Rossi

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Jan 20, 1992, 9:41:50 AM1/20/92
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In article <1992Jan20.0...@chinet.chi.il.us> w...@chinet.chi.il.us (Bill Pfeiffer) writes:
>In article <92019.504...@YaleVM.YCC.Yale.Edu> STA...@YaleVM.YCC.Yale.Edu writes:
>>
>> I need to make a fairly long run of coax cable from an RF distribution
>>amplifier - and I was wondering what problems I could encounter if I used
>>RG58 instead of the standard RG59.... would the difference of the RG58's
>>50ohm impedence as compared to the RG59's 75ohm make a big difference in
>>signal quality, strength, loss over distance, etc. etc.?
>
>The 58 is the '50ohm equivilent of rg 59. There is a thicker 75ohm cable
>out there (possible rg-9) that cable systems use for runs to multi-unit
>dwellings, but it's expensive and if your run is less than 200' don't

RG-58 has somewhat higher losses than RG-59 too.

RG-11 is probably the most common "large" 75 ohm cable available. It
looks like regular RG-8 and runs about the same price (30-40 cent/foot).
It is avalable at most ham radio parts outlets. For really long runs
you are probably better off with regular 75 ohm hardline. You probably
can even get it cheaper if you find the right sources. Rumors are that
some CATV companies may sell/give away odd length "ends of the spool"
pieces if you ask the right person. They may not have much use for
a 100 foot "scrap" piece. This is especially true when they finish
wiring up a new area.

Of course you could end up spending a bit for the hardline connectors.

A good compromise is RG-6 which is similar to RG-59 but has a 100%
aluminum foil shield which makes it almost as good a hardline but at
a fraction of the cost. Available at any Radio Shack.

=================================================================
Pete Rossi - WA3NNA ro...@gvlf8.gvl.unisys.com

Paramax Systems Corporation - a subsidiary of Unisys Corporation
Electronic and Information Systems Group - Valley Forge Labs
Paoli, Pennsylvania
=================================================================

Andrew Lindh

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Jan 20, 1992, 10:06:57 PM1/20/92
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STA...@YaleVM.YCC.Yale.Edu ( @ Yale University) once wrote....

I use RG-6 Aluminax for long runs. It keeps other signals out.
If you use CATV and/or UHF you should stay away from RG59/58.

Loss/100 Feet
Wire Ohms 100MHz 400MHz Cap./Foot Center
RG58 53 4.5dB 10.0dB 28.5pF/Foot 20 Solid
RG59 80 2.9dB 5.9dB 15.6pF/Foot 22 Solid
RG6 75 2.1dB 4.4dB 17.3pF/Foot 18 Solid

If you can't get good wire, try Radio Shack 278-1317 RG-6QS, it
is not bad. The QS is much better than their RG6 or stock made cables.

----
Andrew Lindh
li...@uhasun.hartford.edu li...@hartford.bitnet
and...@werdna.uucp li...@uhasun.uucp

empt...@gmail.com

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Sep 14, 2018, 11:48:50 AM9/14/18
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On Sunday, January 19, 1992, at 2:00:23 PM UTC-5, STA...@yalevm.ycc.yale.edu wrote:
> I need to make a fairly long run of coax cable from an RF distribution
> amplifier - and I was wondering what problems I could encounter if I used
> RG58 instead of the standard RG59.... would the difference of the RG58's
> 50ohm impedance as compared to the RG59's 75ohm make a big difference in
> signal quality, strength, loss over distance, etc. etc.?

Mr. Pfeiffer, good morning. Could you tell me if an RG58 cable can be connected to an RG59 cable and if so what kind of signal loss should I expect, if any? The run is only about 70 feet. The cable is for 1080p security camera.

Any help with this would be greatly appriciated.

Thank you for your time,

Mike Beairsto

Hank Lam

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Oct 4, 2020, 7:44:23 PM10/4/20
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Where did the OP specify the TYPE of RF? That determines the cable, not the size.

Guglielmo Marconi

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Oct 5, 2020, 1:51:02 PM10/5/20
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Just wondering Hank,

Did your C.B. radio break again?

G. Marconi
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