While I love the Panasonic RF-B65, the Voice of Greece and a St. Ambroise Oatmeal Stout: this combo can’t fight the persistent radio interference here at the condo.
Some of you might recall that I’m spending the months of August and September in a condo near Québec City, Canada. We love it here, though it does present some radio challenges. Unlike our rural/remote mountain home in the States, I’ve always had to cope with QRM (manmade radio interference) here at the condo. Not surprising.
I typically bring my PK Loop antenna–it helps lower the noise a tad and is easy to take out on our balcony for optimal reception. Lately, though, the QRM has been even worse on the balcony than inside the condo (more on that in a future post).
Some North American and European stations punch through the noise when propagation is favorable (especially the Voice of Greece and Radio Romania International) but there have been evenings where nothing could penetrate the wall of noise.
Back at the condo, though, there’s no easy way to escape the noise.
Or is there?
Perhaps 21st century problems require 21st century solutions.
This year–especially here at the condo–I’ve spent a great deal of time exploring the KiwiSDR network.
For those of you not familiar, the KiwiSDR is a self-hosted WebSDR which operates much like a mini U Twente WebSDR. KiwiSDR owners install their SDRs at home–or in other favorable locations–then share control of their SDR with the world via the the Internet.
Like the U Twente WebSDR, KiwiSDRs allow multiple simultaneous users to control the SDR independently of each other. Each KiwiSDR can allow up to four simultaneous guests (the U Twente WebSDR can allow hundreds of simultaneous users, but it’s also a university-supported bespoke SDR with fantastic bandwidth!).
Over the past few years, the KiwiSDR network has grown almost exponentially. There are Kiwi SDRs on every continent save Antarctica (someone remedy that, please!).
Each red pin represents a KiwiSDR installation.
Other than the fact that the SDR audio is piped through the Internet–and you can’t walk outside and adjust the antenna–there is no difference between using a KiwiSDR remotely or locally.
In fact, the KiwiSDR only has a web browser-based application, there is no downloadable application for local use. So quite literally, the experience of controlling and using a KiwiSDR locally or globally is identical.
And it’s so much fun! I browse the KiwiSDR network via the map above, select an interesting location, and virtually travel there for an impromptu DXpedition. I can travel to India, Italy, Japan, New Zealand, or Hawaii via the network and be back in time for dinner here in Canada without breaking a sweat or even using frequent flyer miles!
Of course, you don’t need an iPad, or any special equipment. The KiwiSDR application works with pretty much any computer, tablet or smart phone that has a web browser. For the best experience, however, I would suggest connecting a good external speaker, bluetooth speaker or headphones.
I know many of you are thinking, “But Thomas! This isn’t real radio!”
But I would argue that it is real radio! It’s a real radio, connected to a real antenna that you’re simply controlling via the Internet with a web-based SDR application. Instead of the audio going through a sound card into your headphones, it’s going into a soundcard, piped through the Internet, then into your headphones.
Give it a try! You might find an impromptu DXpedition is the perfect remedy to your QRM and RFI blues!
Post readers: Any heavy KiwiSDR users out there? Or do you oppose using WebSDRs? What are your thoughts? Please comment!
I had not checked to see if propagation was good, but tuning to WWV on 10 MHz and 15 MHz confirmed that signals were travelling. In fact, as I started tuning around–first with the CC Skywave SSB, then with the Panasonic RF-B65–I discovered some of the best propagation I’ve experienced in ages!
I did a relatively quick scan covering the 31 through 19 meter bands. Some signals were absolutely booming in.
I jotted down some of the broadcast details on a make-shift log and recorded a few videos.
Note that after making the first video, I discovered I had limited space on my phone, so most of the clips are quite short:
Many thanks to SWLing Post contributor, Mark Hirst, who shares the following guest post:
Micro Go-Box for the ICOM IC-7100
by Mark Hirst
You’ll be familiar I’m sure with the IC-7100 base unit and separate head unit design. It lends itself very nicely for vehicle installation.
Using it in any ‘portable’ situation however has always presented something of a challenge. A FT-857 or FT-891 can be carried as a single physical package with the head unit integrated into the body. The radios can sit and potentially operate on their tail in a backpack, with products like the Escort from Portable Zero making that process even easier.
I’ve had a few attempts at solving this portability conundrum, driven by a concern that there could be long term problems continually connecting and disconnecting the component parts for transport and operation, but knowing that a permanently assembled IC-7100 will always be an awkward dispersed structure.
My first solution was a Stanley 16 inch toolbox, which is fortuitously sized to accommodate the base unit and provides enough space to loop the original connecting cable and head unit. The box is not a bad fit, but certainly bulkier than necessary and leaves enough room for things to rattle around. When tilted vertically, the head unit can start moving.
Fast forward to this week when I discovered that the IC-7100 base unit will also fit inside a 5 litre XL storage box made by Really Useful Boxes:
The XL version of the 5 litre box has a taller lid, and as you can see from the accompanying photos, accommodates the base unit with the head unit sitting on top of it in a ready to use configuration. The tolerances for height are also exact, the VFO knob very lightly touches the lid, so don’t put something heavy on the box:
Once the lid has been removed, the radio can operate directly from the container:
To make the whole thing fit, I used a 25cm CAT 6 cable in place of the original connection cable and a significantly shortened power lead. As luck would have it, I created the shortened power lead a while ago because I often put the battery right next to the radio.
You can see that I removed a section between the power plug and the fuses, and now use the removed length as an extension should the battery be further away. Although it wasn’t my intention at the time, the main part is about 2 feet long, the secondary about 8 inches.
For transport, the power cable is coiled behind the head unit, ensuring the fuse holders sit in the void immediately behind it, while the microphone cable is coiled on top leaving the microphone resting inside its own coil. You can see the arrangement below:
In the next photo, you can see how the cabling emerges from the back of the base unit:
There’s just enough space for the power cable to leave the base and bend around without undue pressure, and likewise for the CAT 6 cable to curve round into the back of the head unit. Two angle connectors make the antenna ports accessible from above, while a short USB external drive cable provides access to the USB port for data modes and CAT control. A longer USB extension cable is attached to this short cable only when required, and the extension uses much more substantial ferrite chokes to mitigate noise from the computer.
To complete the transport package, I’ve cut out a kaizen style foam insert to make sure the base unit can’t move back into the cabling space, and another to make sure the head unit doesn’t slide towards the front.
The last problem of course is cooling. The fan is located in the front of the base unit, with slots along the sides and top to allow air flow. The box unfortunately is exactly the right size for the base, leaving no gaps for air to circulate. In the absence of a proper workshop or professional tools, I opted to use a hole cutter designed for putting pipes through wood panels. It turns out that plastic has a tendency to deform rather than cut under the blades due to friction heating. A sharp knife was essential in dealing with the effects of that deformation to produce the final smooth edges around the holes:
While I’m happy with the port exposing the front fan, the two holes on each side do not completely expose the side slots. Do I drill out the space between them knowing how tricky and flexible the plastic can be, and would a larger hole compromise the strength of the box? For now, I’m going to keep a careful eye for any temperature issues.
The current arrangement is to carry the box horizontally in a cheap travel bag:
Could the box be tilted vertically with the base unit nose down and carried in a back pack for longer excursions? Yes, but experience has told me that the lid latches on Really Useful Boxes have a tendency to pop open when you do that, so a luggage strap around the box may be required to prevent its very expensive cargo from spilling out. I’m also mindful that the box lid gently touches the VFO knob, so might put load on it in the vertical position.
The final result is something of a Swiss watch, and there isn’t much room for error. Things have to be arranged ‘just so’ to fit, but it does mean I can pack and pick the whole thing up in a handy container. The radio only needs a battery and antenna to be connected on site and then it’s ready to go.
There’s something oddly satisfying when unrelated objects come together like this. Who knew that this box was just the right size to fit the radio?
So, what do you think?
Thank you for sharing this project, Mark!
I love your Micro Go-Box: it’s practical, affordable and makes an otherwise awkward field radio easy to deploy and use. Looking at your photos, I realize that the IC-7100 does have one strong suit for field use. The IC-7100 front panel is tilted at a very comfortable 45 degree angle for use.
Post Readers: What do you think? Any other IC-7100 owners out there who take their rig to the field? Please comment!
Many thanks to SWLing Post contributor, TomL, who shares the following guest post as a his Backpack Shack 3 continues to evolve:
Backpack Shack 3.0 – Part 3
I have now gone overboard since I think bigger must be better. The temptation was just too great and now there is an MFJ-1979 17-foot telescoping whip antenna in my car (with consequences).
I have a love/hate relationship with MFJ products because of what I think are useful ideas that are made somewhat poorly. But I went ahead and bought the large whip since I figured they could not possibly screw up something so simple, right?
Wrong. As I excitedly tried to screw the supposed 3/8”-24 threaded end into the nice standard Firestik K-11 magnet mount, I realized I was turning and turning it but it was not going in!!! I even had a small steel sliver of metal sticking into my flesh to prove I was not dreaming. The previous day, it had screwed in very tightly, but it did screw in. So, there I was after a long day of work, ready to listen to some SWL-Nirvana and I could not get the blasted antenna into the mount–? That Firestik mount is a VERY standard 3/8”-24 female thread and the other third-party antenna shafts fit perfectly and easily EVERY time I use them. I hate $60 of poor workmanship and MFJ seems to be the poster child of overpromising and underdelivering.
I was determined to make this work, by force if needed. One of the Trucker antenna shafts by necessity had an extra coupling nut on it to allow the extra 18 inch shaft to connect, so I took it off there and tried to thread it onto the MFJ-1979. It barely moved. Not to be thwarted, I dug out an adjustable wrench and 3/8” socket wrench with ½” socket and grunted and twisted and tightened until the coupling nut was threaded all the way “up its shaft”. That is what I feel like telling MFJ! That coupling nut is never coming off and now that I truly have bought it and cannot return it, I might as well use it.
The stainless steel telescoping rod is extremely thin and feels like it can bend and dent with any kind of mishandling. So it resides collapsed in a 27 inch PVC pipe with plumbing pipe foam inside to baby it when it is not being used. It remains to be seen if I can remember to “Handle With Care” when extending/collapsing it. We’ll see.
OK, so using the 18 inch antenna shaft attached to the magnet mount, then the coupling nut on the MFJ antenna, I extended it to a total of about 13 feet. With the DX Engineering Pre-amp turned on, and using the SDR Play RSP2, I was getting many signals booming in. All the usual names we are familiar with – RMI, CRI, Turkey, Cuba, etc. But also the noise level was very high. I know it is summer but I may have been overloading the Pre-amp a little bit. Here is an example, Radio Progresso from Cuba with some very nice acapella music but also a noisy background (plus, a noisy laptop computer pulse!):
So I decided to come back in the morning before my workday started and see if the static crashes would have died down.
The next morning I had everything hooked up again in the same spot at the Forest Preserve (located in a suburb of Northern Illinois). I moved the Cross Country Preselector to be directly connected from the roof, then to the antenna switch on the “Breadboard” (see part 2) to better prevent overloading. I turned on the Verizon battery pack and nothing. No Pre-amp light. Switched it on, off, on, off – nothing. So, I thought I must have burnt it out the previous session?
Later on, I found it was some sort of short in the switch and I will have to move the D-cell batteries to a backup battery pack. In the meantime, I had to do without the Pre-amp and was forced to extend the MFJ antenna all the way. With the 18 inch extension attached to the magnet mount, that was a total of 18.5 feet from antenna tip to the top of my car roof.
This was actually fortuitous since I was already concerned about overloading the Pre-amp or perhaps amplifying background noise. This forced me to test it in a more “barefoot” manner, hearing what it would natively hear without any Pre-amp. It was also lucky there was no wind to blow it over! It seems that if one is in an RFI-quiet area with decent view of horizons, the 20+dB Pre-amp may not be needed, depending on frequency band involved.
I have read that “Norton” style 10 dB Pre-amps and custom handmade transformer baluns are used by Dr. Dallas Lankford in his Low Noise Vertical antennas. I don’t want to get into winding baluns so I am using one Palomar Longwire Balun to simulate the “magnetic” transfer. His design uses two, one 10:1 at the antenna and a 1:1 balun at the feedline into the house. For more reading on LNV antennas, see these references:
I purposely monitored Voice of Korea for their news statement on the De-Nuke talks on the 25 meter band and found it came in great, just as many others have heard it. This was encouraging. Examining carefully the Data file from the SDR, here is what I pulled from it. I am pleasantly surprised and happy with the results; some stations I had never heard before and the language and music are very exotic. All of it was a little more than one half hour of recording time (14 June 2018, 1300 UTC). You may have to crank up the volume on the weaker recordings to hear those properly.
Taiwan International, 11640 kHz, Chinese, Kouhu Taiwan (blasting in strongly plus strong echo of broadcast at top of the hour – is a second transmitter signal going around the earth the other way and getting to me??)
Eighteen feet of whippy rod can sway in the gentlest breeze (consequences of “bigger must be better”). The described setup has fallen over in as little as a 12 mph sustained wind when fully extended because I had the base in a plastic box. I want plastic under the magnet(s) in order to get it off easily and put away out of sight! Now installed is a larger QUAD magnet mount for better stability:
I am using the flat plastic lid from a 20 gallon tote container under the quad mount and a mover’s tie down strap to the main bar of the quad (I have room for multiple straps if needed). Ten foot fits just fine:
Because the backpack and quad mount can fit inside the 20 gallon tote container, this setup can be attached to a picnic table in a state park or campsite if I choose. The Firestik single magnet mount will be recycled as a VHF antenna mount. I can go virtually anywhere now.
Instead of the 20+dB DX Engineering Pre-amp, perhaps one of those “Norton” 10 dB Pre-amps might be optimal (Kiwaelectronics.com broadband-preamp). And I need to figure out why my Verizon battery pack failed as each Tenergy D cell measured fine. Oh yeah, I have to buy an extra coupling nut, too……
Thanks so much for sharing this latest iteration of the BackPack Shack 3.0, Tom! It seems to me, as you imply, your current setup could be installed pretty much anywhere.
I’m sorry to hear about your troubles with MFJ. I’ve only had good experiences with them in the past, but I suspect the specs on the 3/8”-24 thread were simply incorrect or perhaps metric and mislabeled.
Wanting MOAR options for my recent amplified whip antenna experiment, I decided to add a second antenna input to the kitchen cutting board (can I call it a “Breadboard”? – Ha, that’s an electronics joke!). The idea behind it came from realizing that I might not want to spend all my time outside at a picnic table or on the beach, especially if it is drizzly and windy. And I still wanted a better ground for the antenna. So, I thought I could use more Trucker Parts and put an antenna on top of the roof of my vehicle so I could listen in the relative comfort and safety of my small SUV (or even a friend’s car).
Here is the crowded “Breadboard” with some extra items added.
I thought of the vertical antenna as a short longwire and had an old, original RF Systems Magnetic Longwire Balun. That device allows for an improvement in signal/noise ratio (in theory) if used on a longwire. Perhaps it works on this, too?? You can see the gray cylinder connected right beneath the trucker mirror mount on the left (this will not be tested at this time, see External Antenna below). The output goes to a greenish Daiwa switch on the right.
A large amplified antenna has the real possibility of overloading the amplifier. With the Magnetic Balun, I am hoping the VHF band is attenuated enough to preclude any problems because its response naturally tapers off past 40MHz. But Mediumwave is well within its bandpass. I remembered an old Kiwa Electronics Broadcast Band Rejection filter not being used for a long, long time, so I connected that right after the Daiwa switch (the metal box with red plate).
This output then goes to an RF choke just before entering the pre-amp. I figure I will be using my SDRPlay RSP2 and noisy laptop and wanted to try to reduce any interference traveling on the outside coax braid before it gets amplified.
OK, now for the other Daiwa switch selection. The external antenna will be connected and disconnected as often as I use it. I attached two right-angle coax adapters to be the connection point for the antenna. This is so that the physical switch threads do not have to handle that wear-and-tear. You can see it as the fuzzy out of focus thing sticking up out of the left side switch position.
The wire going out the top of the Breadboard goes to a Firestik K-11 magnetic mount placed on top of the roof of the SUV. I also wanted this to be connected to a magnetic balun. I just happened to have a nearly unused Palomar Engineers Magnetic Longwire Balun. It has its own ground lug for use with a counterpoise. Temporarily, I left the 18 feet of wire that came attached to the K-11 Mount and attached an adapter and BNC test lead; on the other end is connected the spade lugs to the Balun (red wire to the lanyard nut, black wire to the ground lug). It all fits neatly inside a Sistema 3 liter container.
The magnet and box self-clamp easily onto the roof of the vehicle. I added a new 18 inch section to the Trucker Antenna Shafts creating a full 72 inch antenna, complete with mag mount, ground plane (car body), and magnetic balun. It is very easy to put up and take down and the box helps keep everything contained.
I am pushing things a bit here. Magnetic Baluns are not really meant to be used on vertical antennas. It probably breaks some sort of Cosmic Electrical Law somewhere that causes electromagnetic waves to get very confused and die a horrible, twisted, circular death. But I figure that it is an unbalanced “line” similar to a longwire antenna; it’s just a little short and goes straight up instead of horizontal! I like the idea, so I am going to run with it.
It goes without saying that the Antenna Shafts, magnet mount, and magnetic balun are weatherproof (but NOT lightning proof!). Take proper lightning precautions and take it down. Even so, I might add a small drainage hole to the box since it did rain a tiny bit during testing.
Secondly, this setup is ONLY FOR STATIONARY VEHICLES!!!! DO NOT TRY TO DRIVE DOWN THE ROAD OR HIGHWAY!!!! The magnetic mount will NOT stay on the car and will damage your vehicle and maybe a vehicle travelling next to you!
As you can see from the picture, my new Tecsun S-8800 is getting a workout while connected to the Cross Country preselector (not shown behind it) and to the backpack next to the back seat window. The Tecsun S-8800 is a nice radio. My copy has a couple of quirks that I might have to send it back (the AM band tunes incorrectly 2 kHz lower than it should and the SW SSB tunes 140 Hz higher than indicated and I have to compensate using the fine-tuning dial for these modes–FM seems correctly tuned).
Other than this, the actual performance is really quite good! DSP does have sharp cutoffs to the IF bandwidth (especially resolving strong station interference when selecting 3 kHz vs. 4 kHz). With all my filters/balun/choke, I did not notice any MW or FM breakthroughs and signals on those bands were nicely contained and “normal”. Interference from my cell phone while looking up internet frequency listings was minimal – seems like the cable shielding, choke, and car roof are doing a good job.
The audio output jacks have very thin clearance between the jacks and the housing of the radio. So for the second time, I will not have recordings since the cable I wanted to use has home theater style construction with very thick plug outer connectors and will not fit!
From an RF-quiet “Forest Preserve” (County park), there were a variety of stations received from the 25 through 19 meter bands (Local time 11am-1:30pm). A few stations I have never heard before until now:
Radio Free Asia in Korean on 11985 KHz (Tinian Island)
Radio China International in Esperanto on 11650 KHz (Xian China)
Radio Farda in Persian on 12005 KHz (Wooferton England) – broadcast opposite my direction
Radio Bible BCI in Somali on 15310 KHz (Nauen Germany) – Strange sounding but interesting Christian Somali music
Radio Free Asia in Chinese on 13675 KHz (Dushanbe Tajikistan)
Voice of Hope Africa in English on 13680 KHz (Lusaka Zambia) – had to use ECSS USB to get away from strong interference from RFA on 13675, fairly good intelligibility (including music)! I wish there was a 6 KHz option for SSB mode since the audio was slightly muffled and could not compensate much with the tone controls. That kind of feature usually comes with radios costing 3X more, however.
Voice of Korea in French (Kujang North Korea) being squashed by Radio China International (Kashi China) in English on 13760 KHz
It was so nice not to be on a beach and have people walk by STARING at me with my weird radio/antenna setup. And I was dry and comfy sipping a cool drink while there was a drizzle of rain pelting the windshield. Downside might be that the car setup cannot always be located optimally if I want to be next to that Very Large Body of Water (Lake Michigan) to help enhance reception but this is not a bad alternative. The next test will have to be during early evening when signals are booming into my location and see if performance holds up under those conditions!
As always, Tom, a most impressive setup powered by home-grown ingenuity! Thanks so much for sharing the evolution of your field kits with all of us here at the SWLing Post!
By the way, you still have me chuckling about your use of the term, “breadboard!” 🙂
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