[Antennas] zip line

[George, W5YR]

This comment has probably already been made, but usually every year or two
this topic resurfaces and maybe it needs to be made again.

In early days, household extension cords universally used rubber
insulation. Using such for a transmission line was not all that efficient
but it worked. The point is that almost all "extension cord" wire was the
same, so one person's experience likely could be repeated elsewhere. That
was especially true prior to WW2.

Now, "zip cord" is a generic term applied to any extension cable made from
who-knows-what plastic materials. So, it is no longer true that <zip cord>
= <zip cord>. One particular brand may have decent r-f properties and be
useful up to 10 meters (unlikely, but possible). Another using a different
plastic may be useless above 80 meters.

So, we can no longer discuss "zip cord" as a generic commodity generally
available and universally equivalent.

There are zips and there are zips . . .   <:}

73/72/oo, George W5YR - the Yellow Rose of Texas         
Fairview, TX 30 mi NE of Dallas in Collin county EM13qe   
Amateur Radio W5YR, in the 56th year and it just keeps getting better!
QRP-L 1373 NETXQRP 6 SOC 262 COG 8 FPQRP 404 TEN-X 11771 I-LINK 11735
Icom IC-756PRO #02121  Kachina 505 DSP  #91900556  Icom IC-765 #02437

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Dave Henderson wrote:
> 
> QST March 1979 has the data  on ZIP cord as a feedline. In short the losses
> are on the order of 4db/100ft at 14Mhz and 8db/100ft at 28MHz. If you are
> an ARRL member you can still download a copy of the article at;