Big Mag Loop EZNec Plots

Two Big Mag Loops Phased Using the NCC-2

The KY6R “Big Mag Loop” – 25′ circumference with 8′ diameter 

With two of the Big Mag Loops pointing in the same direction – we get this pattern:

Two Big Mag Loops “In Line” and phased offers a nice pattern – both are pointing North and South

Of course, these two aren’t always pointing “in line” – that is possible for North and South (actually slightly NE and SW). If they were both pointing East and West (actually slightly SE and NW):

East and West are the directions when my loops are in this position

When the antennas are phased and pointing in the same direction, either in line or side by side, it seems like the gain and F/B goes up

When the antennas are “juxtaposed” – or off angle from each other, I think the pattern enters a situation where the two work against each other. This is when the NCC-2 can electrically rotate the null so that you use one antenna to null out a noise or other station and then switch in more of the antenna that you want to do the work toward the station you want to hear. It can get very complex.

What is most fascinating about all of this is that you can really start to understand the “three dimensional” nature of radio waves.

KBND – 1100 AM – with a truly local night time pattern – far away from Orinda

This coverage map, courtesy of radio-locator.com is a real testament to how well my phased loops – especially the Big Map Loop are working. As soon as the second Wellbrook FLG100LN preamp arrives, I will put up the second Big Mag Loop. I am really sold now.

Two BIG Reasons To Go With a BIG Mag Loop

The BIG magnetic loop has some really great features

The big mag loop is a little bit noisier than the smaller W6LVP Loop, but its relative to its higher signal level – which is 2 to 3 S units better than the W6LVP. Both loops lets me stay on the air – the heater doesn’t wipe out the band – nor do neighbors electro-crud – and this alone means I am on the way to realizing the whole reason and goal for doing this project.

But the icing on the cake right now is hearing KBND 1110 AM – or any AM station in Bend since they are fairly low power stations, and even though one is a (gag) Fox News station, I’m interested in just hearing smaller AM stations in the smaller markets than the big cities. This speaks well of the weak signal ability of these loops.

 

Trying a Large Magnetic Loop

The NEW KY6R Loop – Now a 25′ Circumference Magnetic Loop – on two 8′ pieces of Redwood

Last night, once I figured out (actually remembered) how the NCC-2 worked – with the two antennas in its 2 inputs, I was disappointed in my “KY6R Optimized 40M Delta Flag”. Sure, it worked, and in a previous test it did work well when phased against the UrbanBeam, but when I compared it to the W6LVP loops – it was noisy and not even as strong as the W6LVP. The W6LVP Loop gave me a more meaningful test baseline. I realized the KY6R Loop was basically a good noise sensing antenna, but NOT something I want. I want something better than the Wellbrook AL1530LNP or the W6LVP Loop.

I ran this by Andy Ikin at Wellbrook, and he said:

“The issue may be down to that the Flag antenna having a 3dB noise figure due to the termination resistance verses the LNP loop having an amplifier noise figure of approx. 0.2dB. Also the LNP by virtue of it small size is picking-up less local noise.

Is your Flag a DHDL or a single Flag? Single Flags and K9AY antenna don’t seem to work in the real world above 2MHz due to signals arriving from too many directions with scattering in the ionosphere.”

BINGO! Andy hit it right on the head, and I then Googled “large magnetic loop” and found a few interesting things. I then opened up an online circle calculator, and looked at what the circumference would be with a frame of 8′ horizontal and vertical pieces. It turns out that its 25′ and that I just happened to have a 25′ piece of LMR-400.

The KY6R Loop is 2 to 3 S units better than the W6LVP Loop, and with its Wellbrook feedpoint preamp and matching system is less noisy, but I will say that the W6LVP Loop is better than the MFJ Loops, but not as good as the Wellbrook ALA1530LNP. I still prefer Wellbrook – but the W6LVP Loop is a fine product, and support from both companies is fast, courteous and educational. I always prefer vendors who take time to make sure you succeed. DX Engineering and Elecraft are also in this “club”.

I just checked 80 and 40M and have found that the KY6R (NEW Magnetic Loop) is a bit noisier – so with the larger size, I pick up more noise as well as more gain – so I will think about what I will do next. Both the small and the large loops are still less noise (and less gain) than the UrbanBeam – on 40M. I might just go with the smaller loop and use the Wellbrook FLG100LN preamps. One idea would be to get some 3/4″ copper ice machine line. As it turns out – I have found that a signal that is Q5 but barely moves the needle is better than S9 swamped with S7 noise – where QSB makes the station fade down in the noise. S Meter readings are not everything!

I think I need to do some A – B tests with weak signals with these two antennas – lets see what I end up with by the time my second FLG100LN gets here – which I hope is before this weekend.

PS – right after I posted this blog entry – the Trane heater kicked in – which totally wipes out the UrbanBeam, but these mag loops let me hear the band. This is very big . . . . AND, I wanted to see if I can hear a low power radio station (5000 watts at night) in Bend, our favorite place – and sure enough, with the BIG mag loop, I can hear KBND on 1110 AM, but with the W6LVP I can hear it, but not nearly as loud. I can’t hear it on either of my regular TX antennas (UrbanBeam and Inverted Vee)

 

Taming The NCC-2 Beast

I’m wrestling with several variables at one time – the NCC-2 is an enigma wrapped in a riddle

The NCC-1 and NCC-2 are very interesting units, but quite “counter-intuitive”. Couple this with two antennas of different types and two different ways to feed these signals into the K3, and to top it off – two antennas can be rotated.

“Tuning for a Null” is the strangest thing. Several things need to bet set up right – you need to have the right “level” on each antenna – using the attenuation switches, and also the balance control. You also need to have the antennas pointed in the right direction(s).The best band (by far) to practice this is the AM broadcast band, and during the night hours – where you have several stations on the same frequency. If you have one strong station – or only one station on a frequency, then there really isn’t much to null out – the best way to think or this is that you have several “competing” stations on a frequency, and what you are doing is nulling out other stations and selecting one. The more AM stations on one frequency, the better.

The other part of this is that the K3 will let you do this with either the RF AUX – where you are doing this on the second receiver, or, you can do this using the RX IN – and then you are switching out the Ant  1 Main (TX) antenna. This seems the best way to practice nulling out stations – one antenna in – receive only, and practice phasing the two antennas plugged into the NCC-2. After you get the hang of it – then moving the input to the second receiver – and then you can adjust the level of your Ant 1 TX with the phased antennas.

I have found a station just over the hill in Berkeley at 1400 AM that is perfect to practice finding the null. Then another station at 1480 that I can’t find a null, but where the phase knob selects one station vs. another.

If you go about this with “gain” on your mind – you will be confused at first – its really a complex “soup” of electrically “steering” the direction and where one antenna can be pointed at one station and the other – another, and the NCC-2 then lets you tune in one against the other.

This means its more of a subtractive process rather than the normal “additive” process. In fact, I just turned off the K3 preamp and on 1480, I can tune in one of 3 stations just using the phase knob and attenuation knobs. Of course, with QSB, this can get really tricky – so its almost best to practice with low power stations that are closer and have less QSB.

I have a lot of practicing and playing and testing to do.

The W6LVP and KY6R Loops both do work – and they do have different characteristics. I will play with these two different antennas this week and see if I can make any determination as far as if one is better than the other. It hasn’t helped that the bands have been pretty crappy lately – from 80M up. This means the only band I can effectively test this on is pretty much the AM BCB.

My main goal this week is to see if a larger antenna – the KY6R Loop is better than a smaller W6LVP loop. I do believe that having two of the same kind antenna will be better than what I have now – a large and small antenna with very different “apertures”, patterns and gain figures.

Maybe practicing during the day on the AM BCB will bear some fruit? We shall see.

 

Spring is On Its Way

The last of last years apples . . .

We have had two days near 70 degrees – so its not out of line to start thinking about Spring.

The last of the fall colors can be found in vines . . . 

The last of the fall colors . . . 

The weather is starting to get warmer – I did not need my jacket yesterday when I rode home from BART on my bike. The days will be 45 minutes longer on January 31 than they were on January 1, and next month, February adds one hour more daylight – which is great news to us bike commuters.

Experiencing a 100 Year Solar Cycle Event?

The MUF has been below 40M this week

Last Sunday I did a test of the KY6R Loop phased with the UrbanBeam using the NCC-2. I was very pleased with the results.

During the week, all of a sudden, it seemed like the results weren’t as dramatic. The reason? 40M really was closed. I dropped down to 80M and heard some activity, then last night I checked out the 160M contest and the band was even quieter and “hot” like 40M usually is.

I was especially thrown for a loop (bad pun intended) because this might be the first time I’ve seen 40M get totally shut down since 2001. During the last bottom of the cycle, I probably just missed this, but it also could be a somewhat historic event. Space Weather has been saying that this bottom of the cycle is a 100 year event.

Anyway, thankfully, the KY6R Optimized 40M Delta Flag works very well on 160 – 20M, and after comparing it to two phased Wellbrook ALA1530LNP’s, which I had just stellar success with, I’m more than ever convinced that the KY6R Loop is better than any small aperature loop, especially because the Wellbrook FLG100LN preamp brings the signal up to unity gain.

It is funny how I doubted myself thinking it was my antenna design and it turns out it’s solar conditions.

Boy, asking questions and using the Scientific Method is critical for success when designing and testing antennas.

In fact, more than any other aspect of ham radio, this is what keeps me in the hobby. CW would be next, and DXing 3rd place.

160M Contest in Win4K3Suite Panadapter

The Win4K3Suite works like a charm – now that I have replaced a bad RS-232 to USB adapter

Years ago, the Keyspan RS-232 to USB adapter was great. Tripplite bought that company and they haven’t updated the driver since 2010. Win4K3Suite kept crashing with this error:

DRIVER_IRQL_NOT_LESS_OR_EQUAL

and the driver was

USA19Hx64p.sys – from Tripplite / Keyspan.

I uninstalled that turkey and replaced it with this:

https://www.amazon.com/gp/product/B006AA04K0/ref=ppx_yo_dt_b_asin_title_o00_s00?ie=UTF8&psc=1

and I am in great shape now. The driver was installed lickity split by WIndows and its a current FTDI driver – no issues.

I was then awarded with one heck of a loud band – 160M is just on fire tonight – DXCC would be so much easier to make compared to when I started chasing it at the top of Cycle 24. Oh well – I made it then, and can now sit back and enjoy watching others chasing it.

One thing I noticed – the MUF has been below 40M lately – wow – that’s something very rare – at least as long as I have been active in ham radio. When Space Weather says we are in a historic 100 year low – I sure see what they mean.

This is important – because I am trying to test an antenna system where there is no propagation. I suspect this is part of being in Winter during the depths of the bottom of cycle 24.