Eric, Again thanks for your splendid research. Looking through the old and new RG214 spec it looks like the Aluminium foil was inserted to improve vertical flame performance.
The foil is in the RF cold area behind the 2 shields, however Im sure there are instances where this foil will corrode and introduce increasing intermodulation with age. This is a shame..looks like RG400 is the only way to go with new installs. Regards Ian G8PWE ----- Original Message ----- From: Eric Lemmon To: [email protected] Sent: Saturday, April 12, 2008 7:38 PM Subject: RE: [Repeater-Builder] New RG-214 Cable has an aluminum tape layer Ian, That information is a surprise, because the current listing shows MIL-C-17/75F, here: <www.dscc.dla.mil/Programs/MilSpec/listdocs.asp?BasicDoc=MIL-DTL-17> No, the MIL-C-17/75F (or 75G, if it indeed exists) are RG-214/U designs. The "new" cable with the foil-backed polyester layer is identified as M17/190-00001. The old "RG" designations are becoming obsolete, which complicates identification. Since the cable OD has not changed, the same connectors will continue to be used. Although I have no official instruction to follow, my personal feeling is to crimp the foil layer with the shields to ensure intimate contact at each end. I'd sure like to know whose idea it was to add an aluminum layer to a fine cable like RG-214/U! 73, Eric Lemmon WB6FLY -----Original Message----- From: [email protected] [mailto:[EMAIL PROTECTED] On Behalf Of IM Ashford Sent: Saturday, April 12, 2008 11:19 AM To: [email protected] Subject: Re: [Repeater-Builder] New RG-214 Cable has an aluminum tape layer Eric, Thanks for doing that research I see a cable spec MIL-C-17/75G in my latest suppliers catalogue. Is this the new cable to which you refer? Also have you seen any information on connectors for this new cable. Specifically, do you remove the foil before crimping the braid ? Ian G8PWE ----- Original Message ----- From: Eric Lemmon <mailto:[EMAIL PROTECTED]> To: [email protected] <mailto:[email protected]> Sent: Saturday, April 12, 2008 5:49 PM Subject: [Repeater-Builder] New RG-214 Cable has an aluminum tape layer The discussion of RG-214/U coaxial cable prompted me to take a look at the current military specifications, and I was surprised to note that a "new" version of RG-214/U cable has arrived. This new version has a one-mil thick polyester tape with an aluminum coating that wraps around the outer shield, with the aluminum side in contact with the silver-plated shield. I have just created a folder in the Files section of this list, entitled Coaxial Cable Specifications. The Military Specification for RG-214/U cable is MIL-C-17/75F. There is also a copy of Amendment 1 to that specification, which makes it inactive for new design and shows RG-214 to be replaced by M17/190-00001. I included a copy of that spec, as well. One might wonder if the "new and improved" cable is more prone to PIM from dissimilar metals than the original. I intend to upload several other specs soon, including RG-58, RG-213, RG-142, RG-400, etc. Stay tuned... 73, Eric Lemmon WB6FLY
