[PVRCNC] n4cwz antenna question

[dave collins]

thanks folks for all of the help!!!!  I'll have to fess up. I think I fried
the balun and line isolator when someone,not mentioned egged me on to try
it on 160!!  I had to take down the fcp when I was doing some grading.
Thanks alot for the consensus that 8x will be ok on 40 and 80.  Yeah Eric I
will cut it for the lower portion of the 80 meter band.  Occasionally???? I
will get on 80 phone but not often. also Eric,yeah I havent had a resonant
antenna in I dont know how long and looking forward to it!  I had a full
wave vertical loop up for 80 and that worked really well but was very
directional.  My plan is for a 80/40 fan. I think it will work much
better.  The knee situation,yeah know about it for 8 years and honestly
wanna get both of them knocked out this upcoming year. One problem is Im
having it done the day before NAQP cw!!  Maybe I will figure out how to
work remote from upstairs to the basement:)   73 es I really appreciate all
the comments. I really really enjoy PVRC. Without a doubt I honestly can
say the best ham related  organization Ive been in   Yall are a great
group!!!  73 and Merry Christmas!  Dave n4cwz

On Sun, Dec 18, 2022 at 11:52 AM Mike Barts <mike at bentwire.net> wrote:

> Dave,
> Howie asked the critical question - was it working before? If so, then the
> question becomes "what changed"? New UPS? new computer? changes to other
> antennas? other changes in the yard?
>
> It could be a break in the shield on the coax creating more common mode
> currents to couple into .... everything. I'd start with a careful
> examination of the connectors on the coax and the feedpoint. If you don't
> have a choke on the feedline, I'd put one where the coax enters the house,
> at a minimum, and, preferably, one near the feedpoint. (Yeah, I know, more
> weight hanging in the air)
>
> Quick anecdote. Last year for FD, we used the existing antennas at the
> Corn Crib, so all the issues were known. Except ... we added an OCFD for a
> digital station. This was hung away from the other antennas as much as
> possible. We had horrible cross band interference whenever we tried to run
> FT8. Think 20/40 sort of interference. Enough so, we pretty much gave up on
> digital contacts. Then Sunday morning, Wayne, KU4V in a last ditch attempt
> tried adding a choke just below the feedpoint of the OCFD. Voila!
> Interference was gone.
>
> Now yours is an RFI issue. But if it's not direct radiation into the
> device (UPS in this case), it's a common mode conducted current issue. You
> may need chokes on the power lines into/out of the UPS. Putting up a fan
> dipole may solve the problem. Or it may just make it different. A choke on
> the coax, before it gets into the house, would be my first (baby) step.
>
> 73, Mike N4GU
>
> PS. if you need some ferrites, our buddy Howie, WA4PSC, (i.e. the OTHER
> Howie) sells them for a good price. Check them out at proaudioeng.com
>
> PPS. Good luck on the knee replacement. On the bright side, you'll have
> more time for CWTs and contests for a while.
>
>
> On Sun, Dec 18, 2022 at 9:35 AM dave collins <davetct at gmail.com> wrote:
>
>> Hi folks,hope everyone is well.  Well i don't know what I did,but my ocfd
>> has become unusable because of rfi on 40 and especially 80. Thought It got
>> into my pc,but it had gotten into my ups!  I'm wanting to put up a fan
>> dipole for 40 and 80. Ordered a balun,so one common feed and I think I
>> will
>> be good. Presently I'm using rg8x.  I think its too small for running more
>> than a kw. Is it??  I've looked and have seen conflicting info on the web.
>> The reason I'm using that is its lightweight . Everything else is lmr 400.
>> So,if yall think its too small,what coax do yall use coming from a dipole?
>> About 150 ft run. I gotta get busy on this as Im having my first knee
>> replacement on the 13th!  thanks and 73 dave n4cwz
>>
>> --
>> ______________________________________________________________
>> PVRCNC mailing list
>> Home: http://mailman.qth.net/mailman/listinfo/pvrcnc
>> Help: http://mailman.qth.net/mmfaq.htm
>> Post: mailto:PVRCNC at mailman.qth.net
>>
>> This list hosted by: http://www.qsl.net
>> Please help support this email list: http://www.qsl.net/donate.html
>>
>
>
> --
>
> ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
> I kin brain inglish and mouth it gud
> ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
>


-- 
Dave Collins
David Collins GC Inc