You’ve Been Warned: Emilio just brought a Grundig Frankenradio to life–!

Many thanks to SWLing Post contributor (and certified mad scientist), Emilio Ruiz, who writes:

Recently I was given a broken Grundig G8 Traveler II. This radio had an accident–the case, speaker, tuning knob, and volume controls were all broken or damaged.

I discovered that the tuning and volume controls are not potentiometers, they are a rotary encoders, so I substituted the tiny and broken original controls with rotary encoders (typically used for Arduino projects), but I needed to remove the 10 kiloohms resistor to work properly (only used the CLK, DT, and GND pins).

All materials were reused from other things, the result is like a “Frankenstein radio”.

The “telescopic” antenna is a tape measure/flexometer which was broken too. I replaced the original speaker (which I think was another impedance) with a proper 8 ohms speaker which produced low volume, so i decide add a Pam8403 amplifier module for best performance. The total current drain is 0.10 amp for a regular “loud” audio level.

So the Grundig Frankie is alive!!… It’s alive!!

Click here to view video in new window.

This is brilliant, Emilio! Although this radio is quite scary–and, let’s face it, “post-apocalyptic”–I think it’s absolutely amazing! I love the handle and the tape measure antenna. You, sir, are a mad scientist and I look forward to your next creation! (I’ll just take shelter first!) 🙂

Anyone else ever created a Frankenradio? Please comment!

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Radio Waves: Radio Marti DRM, Push for Shepparton Museum, APRS on the History Channel, and Radio’s “Major Cultural Opportunity”

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Radio Waves: Stories Making Waves in the World of Radio

Because I keep my ear to the waves, as well as receive many tips from others who do the same, I find myself privy to radio-related stories that might interest SWLing Post readers. To that end: Welcome to the SWLing Post’s Radio Waves, a collection of links to interesting stories making waves in the world of radio. Enjoy!

Many thanks to SWLing Post contributors Alan Hughes, Michael Bird, Zack Schindler, and Dennis Dura for the following tips:

Radio Marti Begins Shortwave DRM Transmissions (Radio World)

Radio Marti began Digital Radio Mondiale (DRM) shortwave transmissions on Feb. 4. Part of the U.S. Agency for Global Media (USAGM), Radio Marti broadcasts news and other programs to Cuba. The DRM shortwave transmissions are from USAGM’s Greenville, North Carolina, site.

USAGM has transmitted in DRM before. There were some transmissions from Briech, Morocco, in the early 2000s. Greenville tested DRM in 2009 in partnership with what was then known as HCJB Global Technology. So why are they back now after an absence of over a decade?

“We want to experiment a bit with different modes and services available on DRM. We also want to help push the development of low-cost receivers and the best way to do that is to put some transmissions on the air, explains Gerhard Straub, director of USAGM’s Broadcast Technologies Division.[…]

Push for museum at Shepparton’s Radio Australia site (Shepparton News)

Amateur radio enthusiasts are pushing for the former site of Radio Australia in Shepparton North to be upgraded and retained as a national museum of radio broadcast history.

Members of the Shepparton and District Amateur Radio Club and The Vintage Radio Club of North East Victoria are due to present a 25-page proposal to an anonymous consortium of buyers said to be interested in acquiring a 258ha block of land along Verney Rd.

The block includes two buildings and several large broadcast towers on the former site of Radio Australia. The site is currently owned by BAI Communications.

The Shepparton club’s assistant secretary, Geoff Angus, said the proposal would be presented to Greater Shepparton City Council for forwarding to the consortium.[…]

APRS usage seen on the History Channel “Secret of Skinwalker Ranch”

Zack Schindler writes:

I have been watching a show about paranormal activity on the History Channel called The Secret of Skinwalker Ranch. In the episode this week they hired a professor to do a balloon launch with some RF sensors. In this episode they also showed the APRS.FI webpage and I was able to read his callsign from an APRS tracker, KM4MRH.

The professor used an APRS tracking device. On the right side of the page link below you can click on Other SSID’s to see other balloon launches he has done. Normally when there is a balloon launch you can see the data from it going up and down. This page shows the Skinwalker balloon launch data transposed over a map. https://aprs.fi/#!call=a%2FKM4MRH-3&timerange=3600&tail=3600

Sadly they are using these for measuring RF fields rather than these.

In a Crisis, Radio Should Be Bigger Than Ever — So Why Isn’t It? (Rolling Stone)

Terrestrial music stations have a major cultural opportunity right now, but employees say a muddied strategy is standing in the way

Radio personality Kevin Ryder was “baffled” by KROQ’s “cold, heartless attitude” when he and his morning-show team were fired at the end of March. The station has long been an alternative/rock staple in Los Angeles, the second-largest market in the country, and Ryder had been on the air for more than 30 years.

“The new people in charge now weren’t here for the building of the world-famous KROQ,” Ryder, one-half of the popular Kevin & Bean Show, said on air when the station let him go, live one final time. “I don’t think it means anything to them. It’s a numbers business, and there’s no family aspect to it anymore. It’s only numbers, but this place was built without numbers. It was musicians, artists, and the special relationship between music, the station, and our fans.”

AM/FM radio provides localized, round-the-clock information and entertainment via friendly neighborhood voices — so in theory, it’s the perfect platform in a global crisis that forces hundreds of millions of people to stay home. But Ryder is one of many in the radio community — including on-air hosts, music directors, program directors — who have been shocked by sudden job losses in recent weeks as COVID-19 has spread across the U.S., and news out of the industry has been one bad thing after another. Why is terrestrial radio missing the opportunity here — and how should it be fighting to get back on top?[…]

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Expectations after dusting off a radio that’s been in storage

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Realistic DX-150A (Source: Universal Radio)

Many thanks to SWLing Post reader, Alfred, who writes:

I purchased a Realistic DX150 radio when it was first introduced. I used it for many years and then stored it away for some time. A few years ago I decided to use it again. After the bandspread control was repaired at a local radio shop, I used it for a short time and then stored it away.

Yesterday, I took it off the shelf to see what was on the air waves. I did not have much success in getting any broadcasts to tune in strongly/clearly. I am writing to ask what my expectations should be – given the low performance of the radio and the state of shortwave transmissions these days. The mechanical aspect of the bandspread control needs attention again. My question is: Should I be able to pick up transmissions at some good level/ quality?

Thank you for your advice and recommendations.

Alfred, thank you for your inquiry and I hope you don’t mind that I’m sharing it here publicly because I’ve been receiving so many similar questions in the past few months.

I assume with so many people sheltering at home because of Covid-19 and, suddenly, having time available to catch up on projects and pastimes, they’re pulling solid-state receivers off of the shelf and putting them on the air again!

You asked: “Should I be able to pick up transmissions at some good level/ quality?”

A simple question, with a potentially complicated answer!

A simple answer first…

If your DX-150 is still electrically and mechanically functioning as it should, and you have it connected to an effective antenna, then yes, you should be able to receive transmissions!

Caveats…

As I’ve told numerous others who have resurrected solid-state gear from storage, there’s a good chance gear that’s a few decades old could have dead or leaky capacitors. Sometimes the symptom of this is a “hum” in the receiver’s audio, but bad capacitors (or “caps” as we like to call them) can also cause less obvious issues with the radio’s overall performance. If you’ve tried everything and suspect your radio needs repair, there are some great repair technicians out there. My friend Vlado is one of them, but I think he may have paused repairs during the Covid-19 pandemic.

Radios that have sat on a shelf or in a basement for years may also have built up oxidization on switch and knob contacts. Carefully applying a product like Deoxit on contacts can make a world of difference and bring your radio back to life.

In addition, if you haven’t hooked up your radio in a couple of decades, you may be surprised by the amount of radio interference and noise (RFI) our home electronics generate. A random wire or indoor antenna that worked well in the 1970s might not work at all if you have high levels of RFI where you live. RFI has the same effect on your radio as a noisy restaurant environment has on your ability to hear a friend who is speaking at a normal volume level across the table from you. RFI can deafen your receiver. There are antennas that can help mitigate RFI, and there are also techniques you can use to help mitigate it.

Depending on where you live in the world, you will find the shortwave landscape isn’t the same as it was, say, in the Cold War years. Fear not! There are still numerous broadcasters out there, so people who say shortwave is “dead” simply aren’t listening. Check out ShortwaveSchedules.com and Prime Time Shortwave for what’s out there and where to find broadcasters on the bands. If you like music, I highly recommend Alan Roe’s guide to music on shortwave.

The Tecsun PL-380 is one of several compact portables that can be purchased for $50 or less.

If you find that you’re not hearing anything on your DX-150 (or other vintage radio)–even after following some of the advice above, yet you still want to explore the shortwaves–you might consider investing in a modern portable radio. Not only do modern portables sport a digital frequency display (which helps locate stations), but they allow you to take your listening to the field. You will be surprised what you can receive when you walk or drive to an area far away from man-made electronic noises. Tabletop radios like the DX-150 are not terribly portable. If you’re looking for some portable shortwave radio suggestions, check out this post. (Incidentally, if you found this post because you’re mainly seeking an AM/FM radio for local news and info, check out this post.)

Getting back on the air…

Alfred (and others who have recently contacted me) I hope this post gives you some helpful guidance. In truth, there are still many other issues that could affect your ability to get the most out of your vintage solid-state receiver. Let’s assume, though, that the solution is simple! Give it a go, and take your time tuning across the bands on different days and with your receiver in different locations.

My hope is that SWLing Post readers will also comment on this post with other suggestions to help you back into the world of SWLing!

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Free Radio Skybird: “One alternative to lockdown lunacy”

New KB6IBB SWL Logger version for MacOS

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Many thanks to SWLing Post contributor, Valery Titievsky, who writes:

Good news from Jeff, KB6IBB.

I’ve waited a long time for this news and it has finally happened!

Jeff has published a new release of his “KB6IBB SWL Logger” now for Mac OS.

It is available as a free download here: https://sourceforge.net/projects/kb6ibbswllogger/

Excellent news! Thank you for sharing this tip, Val!

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FTIOM & UBMP, April 26-May 2

Bruce’s passion for SWLing and single transistor regenerative receivers

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Many thanks to SWLing Post contributor, Bruce (VE3EAR), who shares the following:

I live in the village of Saltford, ON, Canada, near the eastern shore of Lake Huron. It’s a quiet location signal wise, and I’m lucky that I have enough property to erect some big antennas. My two favourites are a 1200 foot long terminated Beverage, aimed at 50 degrees true, which targets Europe and the UK. The other is a 333 foot perimeter delta-loop, apex up and oriented north-south. Both antennas are fed with RG-6 coaxial cables and impedence-matching transformers.

I use the loop with a recently acquired Airspy HF+ Discovery SDR and the Gqrx SDR software, in my iMac. I like to listen to amateur activity on 160, 80, and 40 metres, along with the few shortwave broadcast station that are still on the air. I also like to listen to the trans-Atlantic air traffic control stations in Shannon, Ireland and Gander, Canada.

I once heard a U2 spy plane returning from a mission over Russia!

My other hobby is designing and building simple, one transistor regen receivers, most of which tune the AM broadcast band, although I have built a couple covering the lower portion of the HF broadcast bands as well, just for a challenge. All my receivers are built breadboard style.

My favourite of them is one based upon the Vackar oscillator, with the addition of a diode detector and “Benny”, as is used in crystal radios.

Here is the schematic of the Vackar circuit:

The diode and “Benny” connect to the collector of the transistor, then to a pair of home made headphones using two telephone earpiece elements installed in a pair of hearing protectors. The receiver is both very selective and very sensitive. Here is a pic:

Most of the electronics are on a proto-board, which allowed easy component substitutions during the build. When I had it optimized, I decided to leave it that way! The controls, left to right, are on-off switch, regen, fine tuning, main tuning, and range selector switch, hidden behind the reduction drive. Audio is taken from the DET OUT jack, to either the headphones described above, or to an audio amplifier for listening with a speaker.

Bruce, it sounds like you certainly have an excellent spot and excellent antennas for DXing! I love regen receivers as well and radio design can hardly be more simple.

Thank you for sharing!

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