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inzersv
09-17-2014, 06:47 PM
What does anyone know about LMR-195 Coax cable in place of RG-58 cable? It is advertised as a replacement for RG-58. I am considering using it for my Comm, Transponder and ADS-B antenna cable.

Danzer1
09-17-2014, 08:43 PM
Stan,

There are many brands of 50ohm braided coax cable. RG58 is the cable connector type - not the cable itself. It's almost generic at this point, so easily confused. Having said that the LMR is made by Times Microwave. The LMR-PVC has a pvc outer jacket that is said to be more flexible than the usual polyethylene jacket. I have zero experience with it though.

Greg

inzersv
09-18-2014, 09:35 AM
Thank's Greg. I have zero knowledge of cable, wires and electronics. I am on a huge learning curve here. I will take all advice out there. :confused:

cap01
09-18-2014, 11:01 AM
rg58 has been used for years and years and probably still works fine . rg400 seems to be a replacement and is double shielded . both not to be confused with the shielded cable used for your tv

jrevens
09-18-2014, 11:37 AM
I agree that the RG-400 is the cable of choice for many of us. Not only better (double) shielding, but also high temp insulation around the center conductor (PTFE).

cap01
09-18-2014, 12:16 PM
for the person that will probably not have anything to do with coax other than a Kitfox radio and xponder antenna , heading to a radio shop and say make me a cable would be the easiest and cheapest . by the time a person sorts thru all the connectors , crimpers , strippers and types of cable ,it's well worth the price a shop will charge . for a one time or two time use , it's not worth buying all the required stuff to make four or eight crimps

mr bill
09-18-2014, 07:21 PM
Use of pvc wire insulation in commercial and military aircraft is not allowed because when it burns, it gives off very toxic smoke. It is probably best to minimize its use in our planes as well. I used LMR 240 as a compromise between the RG58 and LMR400 coax. Half the impedance of RG58, not as good as LMR400, but not as large in diameter either.

Av8r_Sed
09-19-2014, 05:08 AM
There's also an eBay seller in Iowa named Dave Medin who makes up quality custom cables. He did an RG400 transponder cable for me delivered for $25.

A sample link: http://www.ebay.com/itm/NEW-Custom-TNC-to-BNC-RG-400-GPS-Com-Transponder-Cable-/131297338415?pt=Motors_Aviation_Parts_Gear&hash=item1e91ee642f&vxp=mtr

Jch
09-20-2014, 05:47 PM
I went to the EAA electronics class (fall 2013) and the instructor recommended I use the RG58. He said his Masters Degree was in antennae. I learned how to build my own cables (comm and elt) not difficult. My SS7 was certified in May 2014 and I flew it to Oshkosh in July. While flying up the Lake Michigan shore line and talking to Chicago approach I asked how my radio sounded...he said it sounded better than most commercial installations. That and landing at Oshkosh were the two highlights of the trip. I routinely hear transmissions from 50-75 miles away at 3500 ft. I have a Garmin GTR-200 btw.

Jch
09-20-2014, 05:49 PM
Correction: the instructor did his Masters Thesis on antennae.

jrevens
09-20-2014, 10:42 PM
With the short runs in our aircraft, it is unlikely you would notice any discernable difference in performance between a good, high quality sample of RG-58, & RG-400. There is less loss with RG-400, it is better shielded and more fire resistant. Also more expensive. I believe it is required in all new certified aircraft.

inzersv
11-01-2014, 02:06 PM
Thanks for all the input on this topic. I broke down and took the EAA Electronics and Avionics Workshop at Paine Field, Everett, WA this past weekend and it was worth the cost and time. I am going to make my own Coax cables because I can and I'm not intimidated by it now. I am going to use the RG-400 cable because of the double shielding. When I got home, I found out my engine had been shipped and will be here next Monday. My prop and nose cone were on the front porch also. I am so excited right now my wife can't stand me! :D