[Lowfer] Lowfer JH Loop Experiment

John Hamer wilbur0611 at gmail.com
Tue Nov 30 20:35:19 EST 2021 

Mike,

I tried the method you mentioned in the earlier email with the led as well
as this last one.  The only way I can get an let to light up is if I touch
one lead to an end if the loop and hold the other. I think the resonance is
just too soft.

I can get a sharp peak with the nano-VNA, but it's just not there with the
transmitter. I think Itll all make sense once I get my Mica's in and do a
better job with the connections.

John Hamer

On Tue, Nov 30, 2021, 7:54 PM N8OOU <n8oou at meekfarm.us> wrote:

> John and the list;
>
> I put a high res image of the simple LED RF Detector on my qsl page.
> The components are one LED, and 1 or 2 diodes. I think the ones in the
> picture are schottky diodes. In the loop tuner that I used on the three
> LF bands, I used only 1 diode.
>
> The pictured unit lights brightly a number of feet away from my 2m
> handheld.
>
> http://qsl.net/n8oou/ledrfdetector.jpg
>
> 73   de   N8OOU - Mike Meek
>
> On 11/30/21 2:38 PM, John Hamer wrote:
> > Mike,
> >
> > My mica's should be in this week and I think that will solve the tuning
> > issue. I bought some old 4ls style ones and some standard through hole
> > ones. They range from 500V to 5KV.
> >
> > I will try the led trick tonight. That will be really cool if it works
> for
> > me. I have never heard of that. I think I have some pretty high turn CT's
> > somewhere, so I will build a current meter when I come across them. I
> need
> > one for this type of stuff anyways.
> >
> > Yes, Your capture does seem to match up. I used the same frequency
> counter
> > to tune it, so it should be at the same place.
> >
> > John Hamer
> >
> > On Tue, Nov 30, 2021 at 3:04 PM N8OOU <n8oou at meekfarm.us> wrote:
> >
> >> John,
> >>
> >> I have used Mylar and polystyrene caps for determining the values needed
> >> to tune the loops. They seem to do ok, but after getting pfff's needed I
> >> have always put Mica HV caps and Air variables on the air.
> >>
> >> I use a simple LED - Diode as an rf detector with one lead connected to
> >> a loop end. The other hanging in free air. Tune for max brightness.
> >>
> >> I also put up this 2020 capture of JH. I was comparing the frequency
> >> from it to last night. Last night the noise level was a lot higher.
> >>
> >> qsl.net/n8oou/JHbeaconJan152020.jpg
> >>
> >> 73   de   N8OOU - Mike Meek
> >>
> >> On 11/30/21 9:11 AM, John Hamer wrote:
> >>> Mike,
> >>>
> >>> Thanks for looking last night. There is definitely something there.
> It's
> >>> hard to tell if there is a JH in there, but it definitely looks like it
> >>> could be.
> >>>
> >>> I am using some met poly capacitors I had right now for tuning the
> loop,
> >>> but I have some mica's on order. I also have a 900pF tuning cap for
> fine
> >>> tuning. Do you have any experience with Met Poly caps with something
> like
> >>> this? They claim to be pretty stable. Something is changing after the
> >>> transmitter cuts on. I am tuning the antenna using a nanoVNA. The
> current
> >>> on my final looks exactly correct for the 50Ohm load every time the
> >>> transmission starts, but over the next 30 seconds to 1 min the current
> >>> slowly drops. I'm not sure if the capacitors are warming and changing
> >> value
> >>> or if there is just a connection issue with them in a breadboard. I
> will
> >>> remove one of those possibilities when I solder everything together,
> but
> >> it
> >>> kinda looks like it's just coming out of tune. I also need to build
> >>> something to measure antenna current. I should have it all next week
> >>> sometime.
> >>>
> >>> Finals are staying cool and frequency is stable.
> >>>
> >>> The link below has some pictures.
> >>> http://jwhamer.me/lowferJH/Loop2021/
> >>>
> >>> John Hamer
> >>>
> >>> On Tue, Nov 30, 2021 at 7:55 AM N8OOU <n8oou at meekfarm.us> wrote:
> >>>
> >>>> John,
> >>>>
> >>>> Thanks for the info, I can relate your results to the tests I made
> using
> >>>> Quad Shield RG6 and RG8.
> >>>>
> >>>> I shut down WM to listen overnight. Nothing seen until Gray Line this
> >>>> morning. See the first capture at;
> >>>> http://qsl.net/n8oou/nov29210006.jpg
> >>>>
> >>>> I have a second screen comming, it looks like you went qrt at 06:30
> CST.
> >>>> The filename will be nov29210007.jpg when it's ready.
> >>>>
> >>>> 73   de   N8OOU - Mike Meek
> >>>>
> >>>> On 11/29/21 8:58 PM, John Hamer wrote:
> >>>>> Mike,
> >>>>>
> >>>>> I actually have some pretty good size litz wire. It looks to be
> around
> >> 3
> >>>> or
> >>>>> 4mm diameter.  Ill see if there is a label on spool with more
> >>>> information.
> >>>>> I'm not sure if the spool came with the wire.  I got it from my last
> >> job
> >>>>> years ago when they were trashing it.
> >>>>>
> >>>>> I still have everything breadboarded, so I'm not sure if that is
> >> causing
> >>>>> any issues,  but I will solder it all together in the next few days
> >>>>>
> >>>>> John
> >>>>>
> >>>>>
> >>>>> On Mon, Nov 29, 2021, 9:52 PM N8OOU <n8oou at meekfarm.us> wrote:
> >>>>>
> >>>>>> John,
> >>>>>>
> >>>>>> Good to have another loop experimenter. I am curious about what you
> >> are
> >>>>>> using for the loop conductor. My experiments have shown the larger
> the
> >>>>>> conductor, the better.
> >>>>>>
> >>>>>> Good Luck
> >>>>>>
> >>>>>> 73   de   N8OOU - Mike Meek
> >>>>>>
> >>>>>> On 11/29/21 5:17 PM, John Hamer wrote:
> >>>>>>> I have a 12'x12' square loop setup. I am transmitting my usual mode
> >> of
> >>>>>>> qrss60 and a graphic on 181.818KHz. I just got it going tonight and
> >>>> still
> >>>>>>> have some work to do, but if you are looking for a challenge, give
> >> it a
> >>>>>>> shot! It is aimed in the N/S direction.
> >>>>>>> ______________________________________________________________
> >>>>>>> Lowfer mailing list
> >>>>>>> Home: http://mailman.qth.net/mailman/listinfo/lowfer
> >>>>>>> Help: http://mailman.qth.net/mmfaq.htm
> >>>>>>> Post: mailto:Lowfer at mailman.qth.net
> >>>>>>> Post must be less than 50KB total for message plus attachment!
> >>>>>>>
> >>>>>>> This list hosted by: http://www.qsl.net
> >>>>>>> Please help support this email list:
> http://www.qsl.net/donate.html
> >>>>>>>
> >>>>>> ______________________________________________________________
> >>>>>> Lowfer mailing list
> >>>>>> Home: http://mailman.qth.net/mailman/listinfo/lowfer
> >>>>>> Help: http://mailman.qth.net/mmfaq.htm
> >>>>>> Post: mailto:Lowfer at mailman.qth.net
> >>>>>> Post must be less than 50KB total for message plus attachment!
> >>>>>>
> >>>>>> This list hosted by: http://www.qsl.net
> >>>>>> Please help support this email list: http://www.qsl.net/donate.html
> >>>>>>
> >>>>> ______________________________________________________________
> >>>>> Lowfer mailing list
> >>>>> Home: http://mailman.qth.net/mailman/listinfo/lowfer
> >>>>> Help: http://mailman.qth.net/mmfaq.htm
> >>>>> Post: mailto:Lowfer at mailman.qth.net
> >>>>> Post must be less than 50KB total for message plus attachment!
> >>>>>
> >>>>> This list hosted by: http://www.qsl.net
> >>>>> Please help support this email list: http://www.qsl.net/donate.html
> >>>>>
> >>>> ______________________________________________________________
> >>>> Lowfer mailing list
> >>>> Home: http://mailman.qth.net/mailman/listinfo/lowfer
> >>>> Help: http://mailman.qth.net/mmfaq.htm
> >>>> Post: mailto:Lowfer at mailman.qth.net
> >>>> Post must be less than 50KB total for message plus attachment!
> >>>>
> >>>> This list hosted by: http://www.qsl.net
> >>>> Please help support this email list: http://www.qsl.net/donate.html
> >>>>
> >>> ______________________________________________________________
> >>> Lowfer mailing list
> >>> Home: http://mailman.qth.net/mailman/listinfo/lowfer
> >>> Help: http://mailman.qth.net/mmfaq.htm
> >>> Post: mailto:Lowfer at mailman.qth.net
> >>> Post must be less than 50KB total for message plus attachment!
> >>>
> >>> This list hosted by: http://www.qsl.net
> >>> Please help support this email list: http://www.qsl.net/donate.html
> >>>
> >> ______________________________________________________________
> >> Lowfer mailing list
> >> Home: http://mailman.qth.net/mailman/listinfo/lowfer
> >> Help: http://mailman.qth.net/mmfaq.htm
> >> Post: mailto:Lowfer at mailman.qth.net
> >> Post must be less than 50KB total for message plus attachment!
> >>
> >> This list hosted by: http://www.qsl.net
> >> Please help support this email list: http://www.qsl.net/donate.html
> >>
> > ______________________________________________________________
> > Lowfer mailing list
> > Home: http://mailman.qth.net/mailman/listinfo/lowfer
> > Help: http://mailman.qth.net/mmfaq.htm
> > Post: mailto:Lowfer at mailman.qth.net
> > Post must be less than 50KB total for message plus attachment!
> >
> > This list hosted by: http://www.qsl.net
> > Please help support this email list: http://www.qsl.net/donate.html
> >
> ______________________________________________________________
> Lowfer mailing list
> Home: http://mailman.qth.net/mailman/listinfo/lowfer
> Help: http://mailman.qth.net/mmfaq.htm
> Post: mailto:Lowfer at mailman.qth.net
> Post must be less than 50KB total for message plus attachment!
>
> This list hosted by: http://www.qsl.net
> Please help support this email list: http://www.qsl.net/donate.html
>

More information about the Lowfer mailing list