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Author Topic: RG58 vs. RG174 vs. RG316 for Receive Only  (Read 10993 times)

Offline bandarr3000

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RG58 vs. RG174 vs. RG316 for Receive Only
« on: October 24, 2017, 0318 UTC »
I currently have RG174  and RG316 cables connected in series to my SDR, which I use to listen exclusively to HF.  Am I better off with RG58?  I guess maybe my real question is, is there any difference in receive performance between RG174, RG316 and RG58?  Is one more susceptible to RFI than another? Thanks.
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Offline redhat

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Re: RG58 vs. RG174 vs. RG316 for Receive Only
« Reply #1 on: October 24, 2017, 0637 UTC »
Shielding effectiveness at lower frequencies is not usually a problem except in rare cases.  Even loss at 10 or so MHz isn't going to be real bad unless the cable is very long, maybe 100' or so.  Bang for the buck wise, RG-6Q is probably the best most ready available cable out there for receive.

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Offline Oliver

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Re: RG58 vs. RG174 vs. RG316 for Receive Only
« Reply #2 on: October 24, 2017, 0914 UTC »
From my prospective, three factors are interesting when looking into coax.
The shieling, attenuation & impedance.

Here a with the mentioned coax comparison:

Shielding
RG 58/U  (20AWG) - 78% coverage with Bare  Copper Braid Shield
RG 174/U (26 AWG) - 90% coverage with Tinned Copper Braid Shield)
RG 316  (26 AWG) - 95% coverage with Silverplated Copper Braid Shield
H155 - 100% Duofoil + 80% coverage with Tinned Copper Braid Shield

Attenuation (dB/100 meter)


Coax         10 Mhz     20 Mhz     28 Mhz     50 Mhz   
RG 58/U    4,5           6,5            --             10,4      (50 Ω)
RG 174/U  9,5           13,5          --             18,5      (50 Ω)
RG 316     8,2                            17,0         19,2      (50 Ω)
H155        3,0            4,2            4,9          6,5        (50 Ω)

This summer I change all my coax from RG 58 to H 155.
So far, I am pleased with the change. My noise floor went down by 5-8dB depending on the antenna.
The cost for the H155 is almost double, compared to the RG 58. However, in my situation it was worth it.
A must in my opinion is also good grounding of the coax shield and a common mode choke in each coax line.
« Last Edit: October 24, 2017, 1319 UTC by Oliver »
RX: Elad FDM-S2, Grundig Satellite 700 & Yaesu FRG-7
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Please send eqsl to: oliverinusa[at]yahoo.de

Offline ChrisSmolinski

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Re: RG58 vs. RG174 vs. RG316 for Receive Only
« Reply #3 on: October 24, 2017, 1053 UTC »
Shielding effectiveness at lower frequencies is not usually a problem except in rare cases.  Even loss at 10 or so MHz isn't going to be real bad unless the cable is very long, maybe 100' or so.  Bang for the buck wise, RG-6Q is probably the best most ready available cable out there for receive.

+-RH

Agreed. I use RG-6 everywhere now. For receive only applications, 75 vs 50 ohms is a non issue. It's cheap, effective, and easy to find.  Every so often I'll find unused 50 ft runs of it at thrift stores for $3 or so.
Chris Smolinski
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Offline pinto vortando

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Re: RG58 vs. RG174 vs. RG316 for Receive Only
« Reply #4 on: October 24, 2017, 1149 UTC »
Another vote for RG-6.   Been using it here for the past several years on various of my antennas from AM BCB through UHF and it works fine.  The 75 ohm thing is no issue on RX and has not been a problem on TX either.  The cable and the "F" connectors are easy to find and inexpensive and easy to install.  A wide range of adapters are available to go from F to UHF, BNC, RCA, whatever.
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Offline bandarr3000

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Re: RG58 vs. RG174 vs. RG316 for Receive Only
« Reply #5 on: October 25, 2017, 0117 UTC »
Thanks all.  Any reason I should switch out the RG8x I have outside for RG6?
Yaesu FTDX3000D
SDRPlay RSP1A
W6LVP loop antenna
EFHW 40-10 as inverted L
Grand Rapids, MI

eQSL please to bandarr@gmail.com

Offline pinto vortando

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Re: RG58 vs. RG174 vs. RG316 for Receive Only
« Reply #6 on: October 25, 2017, 0855 UTC »
Thanks all.  Any reason I should switch out the RG8x I have outside for RG6?

At HF, RG-6 has slightly lower loss than RG-8X but IMHO not enough to justify switching out the 8X if the 8X is in good shape.
However, for future projects, consider using RG-6.  In comparison to other commonly used coax, it is more readily available, easier to work with, has low loss, and less costly.
Das Radiobunker somewhere in Michigan