Every amateur radio operator is attracted to different aspects of our diverse hobby. For Cliff Batson, N4CCB, of Nashville, Tennessee, it’s QRP — making radio contacts with 5-watts or less.

“I’m not an expert, but I have quite a bit of passion and enthusiasm for QRP. There’s just something magical about being able to make contacts using less power than a nightlight,” says Batson.

Batson started a video blog called QRP School late last summer and recently added his twentieth episode. He’s already covered topics like using a deploy-anywhere vertical HF antenna (below), solar power operations, building a computer-to-CW interface, bringing your gear along on vacation, and many more. He says that he hopes to add even more QRP-related videos soon.

“Ham radio is a big hobby, and there’s room for all of us to enjoy whatever we enjoy, while letting others do their own thing,” he says.

If you enjoy QRP or want to learn more, you can visit his site at QRPSchool.com and subscribe to his YouTube channel.

Matt Thomas, W1MST, is the managing editor of AmateurRadio.com. Contact him at editor@amateurradio.com.

Here is this week’s space weather and geophysical report, issued 2016 Feb 15 0238 UTC.

Highlights of Solar and Geomagnetic Activity 08 – 14 February 2016

Solar activity was low from 08-11 Feb. The largest C-class event during that period was a C8/1f observed at 11/2103 UTC from Region 2497 (N13, L=087, class/area Eac/250 on 12 Feb) with associated Type II (est. speed 483 km/s) and Type IV radio sweeps. A CME was visible following this event and is anticipated to arrive at Earth early on 15 Feb. Solar activity was moderate from 12-14 Feb with Region 2497 producing an M1 flare each day. No other Earth-directed CMEs were observed.

No proton events were observed at geosynchronous orbit.

The greater than 2 MeV electron flux at geosynchronous orbit was at normal to moderate levels during the period.

Geomagnetic field activity began the week at minor storm levels due to effects from a co-rotating interaction region (CIR) ahead of a CH HSS. Predominately quiet to unsettled levels were observed for the remainder of the period with isolated active periods on 09, 11 and 12 Feb associated with extended periods of negative Bz.

Forecast of Solar and Geomagnetic Activity 15 February – 12 March 2016

Solar activity is expected to be at very low to low levels with a chance for M-class flares from 15-17 Feb. Activity is expected to decrease to very low levels with only a chance for C-class flares from 18-29 Feb as Region 2497 moves beyond the west limb. Low levels are anticipated once again on 01-12 Mar as well as a chance for M-class flares with the return of Region 2497.

A slight chance for a proton event exists at geosynchronous orbit from 15-17 Feb due to the flare potential and position of Region 2497.

The greater than 2 MeV electron flux at geosynchronous orbit is expected to be at normal to moderate levels for the majority of the period. High levels are likely on 18-20 Feb following effects from a CME and a subsequent CH HSS.

Geomagnetic field activity is expected to reach minor storm levels on 15 Feb due to effects from the 11 Feb CME. Quiet to active conditions are expected on 16 Feb as CME effects subside. Minor storm conditions are likely again on 17 Feb as a recurrent negative polarity CH HSS becomes geoeffective. Quiet to unsettled conditions are expected with isolated active periods possible on 18-20 Feb as CH HSS effects continue. Mostly quiet conditions are expected on 21-29 Feb. Quiet to unsettled conditions are expected from 01-03 Mar due to effects from a positive polarity CH HSS. Mostly quiet conditions are expected for the remainder of the period with unsettled to active periods possible on 06-07 Mar and 11 Mar as two sequential small recurrent coronal holes affect the field.

Don’t forget to visit our live space weather and radio propagation web site, at: http://SunSpotWatch.com/

Live Aurora mapping is at http://aurora.sunspotwatch.com/

If you are on Twitter, please follow these two users: + https://Twitter.com/NW7US + https://Twitter.com/hfradiospacewx

Get the space weather and radio propagation self-study course, today. Visit http://nw7us.us/swc for the latest sale and for more information!

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Visit, subscribe: NW7US Radio Communications and Propagation YouTube Channel

AmateurLogic.TV Episode 87 is now available for download.

Tommy explores FLDigi with his Icom IC-7100 and Mac computer. Peter’s Introduction to Satellite TV Pt 2. Emile visits Hammond Hamfest and Crossband repeats. Plus lot of fun and a few headaches.

1:08:20

Download
YouTube

George Thomas, W5JDX, is co-host of AmateurLogic.TV, an original amateur radio video program hosted by George Thomas (W5JDX), Tommy Martin (N5ZNO), Peter Berrett (VK3PB), and Emile Diodene (KE5QKR). Contact him at george@amateurlogic.tv.

I have been using small footprint computers in ham shack for a while. It started with the Dell Zino. Always a bit under powered, but enough to get the hamming done. The latest computer driving everything was one of those barebones models that was the size of a shoe box. The first sign of decline was when the fan kept getting louder and LOUDER. The the drive (500GBs of SATA) then decided to give up the ghost.

An immediate lesson learned… back up my log. I have been good at uploading my logs (almost daily, when on the air) to LOTW, QRZ.com, and eQSL. But I would only export that days contacts, consistently replacing the previous days exported log.

I choose not to abandon the small footprint computer and went back to the Shuttle. Newegg.org was my one stop shopping:

The case and motherboard: Shuttle XH81 Intel Core i7 / i5 / i3 / Pentium / Celeron 65W Intel H81 1 x HDMI Barebone system
– small form factor, fits neatly underneath monitor.
– 2x RS-232 connections on the back. Perfect for connecting to the Elecraft amp and tuner.
– Plenty of USB connections

Intel Core i7-4770S Haswell Quad-Core 3.1 GHz LGA 1150 65W BX80646I74770S Desktop Processor Intel HD Graphics
– not the fastest, but fast enough.
– comes with a super quiet fan.

Transcend JetRam 8GB 204-Pin DDR3 SO-DIMM DDR3 1600 (PC3 12800) Laptop Memory Model JM1600KSH-8G
– I got two DIMMs to keep things moving… 16GBs = snappy!

SAMSUNG 850 EVO 2.5″ 250GB SATA III 3-D Vertical Internal Solid State Drive (SSD) MZ-75E250B/AM
– Good bye disk, hello solid state. Faster. Silent.

The actual build was plug and play. The Shuttle line has come a long way since my last experience with their product. I think these specific computers are designed to operate older types of technology (hint…. 2x RS-232 connections?) which works great with most amateur radio needs.

The next step was loading the OS. LiLi USB Creator is my go to solution for installing linux when I don’t have an optical drive (which is more often the case). This allows you to load the OS through booting directly from the USB stick.

The linux flavor of the day: Mint with the MATE edition. I was an Ubuntu man until Unity. Then made the jump to Mint. The OS loaded without issue and I was off and running.

Amazingly enough, I was able to install TQSL-2.2. In the past, I have been able to install TQSL from the Software Manager. But this has been an older version of TQSL. The newer versions ALWAYS gave my problems with dependency issues during attempted installs. I stayed with it this time and finally got it working. Phew!

The install of fldigi went smoothe, but configuring it to work with my Elecraft K3 was giving me fits. In my past setup, I’ve always used hamlib for rig control and the trick was just finding which USB number was being used for my USB Microham III. But this time, the USB Microham III was identified by name as a choice. Great! But it didn’t initialize. I tried USB0 (…. nothing), combed over the results of lsusb…. not… working. After some intense Googling, I ran across a command I had never seen before:

sudo adduser [username] dialout

Dialout!? Who knew? But that did the trick.

Now, here is something funny. We all have our junk boxes. As hams, we are pack rats. We hang on to stuff that has no current use, but may someday. I had a box RS-232 cables. When Fall Cleaning swept through the ham shack, I looked at the RS-232 cables. I am really going to need 15 RS-232 cables ranging in length between two and 15 feet? The box headed to the dump.

Now, with my growing K-Line, I can use Elecraft software (linux versions available) to monitor data from the amp and tuner. But the connections are serial. SERIAL. I turned the ham shack upside down and not an RS-232 cable to be found. I really don’t want to have to actually go out and BUY a serial cable.

Scott Hedberg, NØZB, is a regular contributor to AmateurRadio.com and writes from Kansas, USA. Contact him at n0zb@arrl.net.

The finished product

1. Rewire the internals of the unit each time I switch radios, this was just not an option as it is time consuming and the unit I believe over time would not stand up to these continual wiring change outs.
2. To purchase Signalinks plug and play boards, you simply plug in the board for the K3 or the KX3. This is for sure an option but again I was wanting to not take the Signalink apart each time I wanted to change out the radios.
3. There is also the option of purchasing a second Singalink USB unit but this is very pricey for what I wanted to do.
4. Try to figure out if it is possible to set up the internals so with the simple flip of a switch mounted on the outside of the unit I could change the internal wiring to make either the K3 or KX3 work. This was the option I decided to work on.

   internal mod wiring

Mike Weir, VE9KK, is a regular contributor to AmateurRadio.com and writes from New Brunswick, Canada. Contact him at ve9kk@hotmail.com.

courtesy: http://www.leeszuba.com/projects/

A recent blog posting of four videos showing the installation of a new (Roelof-made) PAØRDT active E-probe antenna revealed that there appeared to be a difference between his earlier model and his latest. It was noticed that the noise ingression levels were different between them, with one showing less noise on LF than on HF, while the other one behaved just the opposite. The newer PFU has the antenna ground isolated from the receiver's ground while the older one does not. Noise coupling, with the new one was higher on HF and lower on LF, which was just the opposite of what was noted with the older unit with its un-isolated ground ... overall LF performance over the newer system was deemed to be better as seen in the final video here.

The only difference seemed to be in the coupling isolation transformer, used in the power feed unit (PFU), likely similar to the one shown at the bottom of this page.

Roleof's transformers are wound on a Magnetics 0W40705TC toroid, whose high mu ferrite has an Al value of ~8350. I mentioned to Roelof that is seemed unusual that the noise levels would be greater on HF than on LF, with the new transformer, as usually it's the other way around when it comes to noise. The changes noted in the video lead to further transformer testing by Roelof, who indicated :

The isolating transformer consists of two bifilar windings on a high mu core. My guess is that the interwinding capacitance spoils the isolation at HF. I have just tested an isolating transformer with two separate windings opposite each other on the tiny core. Sure enough, this solves the feedthrough at HF and VLF performance is not impaired at all.
I have never given this a second thought as I believed it was specific for my location. Never too old to learn!

I have evaluated both transformer types on my spectrum analyser and
found the following.

The current transformer with a twisted bifilar winding is a
transmission line transformer. In a 50 ohm system, it covers 4 kHz (!) to 200 MHz at -3dB. Which is very good.

The new one, using the same core and separate windings is an other
story. It covers just 4 kHz to 8 MHz at -3dB. At 30 MHz the loss is
13 dB. So, excellent for VLF / LF/ MF, it won't do for upper HF.

I will try other core material and see if a feasible compromise is
possible.

To be continued.

further...

I first tried a FT-37-43 toroid with 10 turns for each winding.
This core is suitable for higher frequencies and I expected it to
work better than my high mu (8300) cores.
Nope, it was far worse and at 30 MHz the loss was already > 20 dB.

I reverted back to my magical cores and reduced the number of turns
to 3. This yielded a nice bandwidth (-3dB)from 50 kHz to 50 MHz.

Used in the mini-whip interface, there is no more a difference
between shared grounds and isolated grounds on either VLF / LF or
HF.

Though the lower -3dB point is at 50 kHz, I still have excellent
reception of the Russian Alpha stations between 10 and 15 kHz.
It looks like this transformer is an excellent compromise for this
purpose.

I have often found that in practice, high mu cores are excellent for
wideband transmission line transformers. They are good for
traditional rf transformers as well!

and:

I just have tested a binocular core, the BN-73-202, available from
W8DIZ.

With two windings of two turns each of insulated hook up wire (to
keep interwinding capacitance low), gives a transformer from 80 kHz
to over 100 MHz. In practice reception down to 10 kHz is still
excellent.

There is no difference between isolated or common grounds either.
The coupling with this binocular core is a little better than with a
toroid. At LF / MW, I don't find any loss at all.

The FT-50-75 will do fine with two windings of 4 turns each.
I have some FT-50-77 cores at hand and will see how they work out.

I am surprised at the wide bandwidth that can be achieved.

and:

I have been testing a FT-50-77 ferrite toroid for use as wideband
isolation transformer.

Three turns on the Magnetics (aka magical) cores, give an inductance
of 60 uH. Used as a wideband Isolation transformer, the -3dB
bandwidth ranges from 80 kHz to 50 MHz.

For about the same inductance, the FT-50-77 core needs 6 windings.
Used as wideband isolation transformer, the lower - 3dB point is 100
kHz, the upper is 12 MHz. At 30 MHz the loss is already 8.5 dB.
Though not suitable as wideband isolating transformer, it still can
be used for the range 100 kHz - 3 MHz.

It looks that for good wideband performance the Al value must be >
5000 and the number of turns should be =< 3.

Interesting stuff and the best thing is that it has really lowered
my noise floor!

A summary posting to the RSGB's LF reflector indicates that the new transformer scheme is providing quieter VLF reception and good performance up to 200MHz

For years, I have been using a rf - isolating transformer to
separate antenna and receiver ground.

This is a home made transmission line transformer, consisting of 11
bifilar turns on a small high mu toroid (AL=8300). The inductance is
1.2 mH. The measured -3dB bandwidth in a 50 ohm system covers 4 kHz
- 200 MHz.

It appeared that the isolation was not perfect, due to the
inter-winding capacitance. I have made a new transformer on the same
core with two windings of each tree turns. The windings are opposite
each other on the core. The bandwidth is now 45 kHz - 50 MHz. The
loss is 1.3 dB.

Despite the raise in the lower -3dB point, reception at VLF is much
improved due to lower noise ingress. See attachment.
The screen runs from 1 kHz - 13 kHz. At the right hand the dashes
from the Russian Alpha system can be seen. The white band is with
common ground. Harmonics of the 50 Hz mains can be easily spotted.
In reality the picture will be better,as the sensitivity of the
PERSEUS drops considerable below 10 kHz.

The level of interference on 380 kHz caused by a plasma TV in the
neighbourhood is also much reduced.


An excellent video demonstrating the dramatic effects of isolating the ground in the e-probe antenna system on LF was posted today by PY3CRX. Marcus used the Magnetics hi-mu core with 5 + 5 turns (~ 390 + 390 uh).


For those not having access to the Magnetics material, it looks like the BN-73-202 binocular core is a good performer, from 10kHz - 100MHz. The FT-75 and 77 material also fair well but with differing bandwidths. Cores are available from Amidon as well as from W8DIZ's Kits & Parts.
Steve McDonald, VE7SL, is a regular contributor to AmateurRadio.com and writes from British Columbia, Canada. Contact him at ve7sl@shaw.ca.

Amateur Radio Weekly is curated by Cale Mooth K4HCK. Sign up free to receive ham radio's most relevant news, projects, technology and events by e-mail each week at http://www.hamweekly.com.