I just checked the coax I used. It has the stranded center conductor. I
can't find the part number on it. I would hve to find the invoice. But it
is the mil spec teflon/silver coax.
K4TO
The antenna is working now. I'm suspecting the relay position on the
remote switch. As soon as it stops raining, I will check it out. Thanks
for for all the advice.
K4TO
On Sat, Jul 2, 2022 at 11:57 PM Grant Saviers <grants2@pacbell.net> wrote:
> A minor matter, but RG142 center conductor is SCCS - silver plated
> copper coated steel. That makes it very strong but fatigue prone. Some
> are concerned about TFE creep from the solid conductor and recommend
> stranded RG400 as a result. However, I've not had problems in FT-240
> toroid chokes wound 10 years ago with 142 made from Mil 17/60-RG142 spec
> cable.
>
> Paternack specs their 142 at 2400w average power at 100MHz. It will get
> hot, but the TFE handles it. Best to provide easy dissipation of the
> heat as K9YC recommends.
>
> Another possible issue is to keep ferrite toroids away from the boom and
> other conductors as the coupling can cause problems.
>
> Grant KZ1W
>
>
> On 7/2/2022 16:13, Jim W7RY wrote:
> > Agreed.
> >
> > RG-400 works well to. The only difference between RG-142 and RG-400, is
> > that RG-400 has a stranded center conductor. RG-142 has a silver plated
> > solid hard drawn copper center conductor.
> >
> > 73, Jim W7RY
> >
> >
> > On 7/2/2022 6:09 PM, john@kk9a.com wrote:
> >> The 50MHz power average rating for RG142 is several kilowatts, why do
> you
> >> think it is inadequate?*If it is a balun problem it is most likely
> >> connection related.*
> >>
> >> John KK9A
> >>
> >>
> >>
> >> Dave Sublette k4to wrote:
> >>
> >> My six element 6M LFA is showing a high SWR and severe loss of receive
> >> signal. This happened this afternoon as I was working the band with 500
> >> watts from my KPA500.
> >>
> >> To this point, the antenna was very nicely matched with a 1:1 SWR over
> >> almost 1 MHz of bandwidth. The antenna is home brew and I made the
> >> matching
> >> balun per the instructions from K9YC using two toroids with six turns
> >> each
> >> of high quality teflon insulated, double shielded silver braid. I
> >> think it
> >> was RG142 purchased new from a reputable vendor in Tennessee. It has
> >> worked
> >> perfectly at the 100 watt level for three or four years. I had looked
> at
> >> the specs on the coax and thought it would be good for 500 watts.
> >> Evidently not.
> >>
> >>
> >> 73,
> >>
> >> Dave, K4TO
> >>
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> >>
> >>
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