Category Archives: Articles

Ken’s E. H. Scott Philharmonic Beam of Light console radio

In response to an inquiry in our post about the Crosley WLW Model Super-Power Radio Receiver, SWLing Post contributor, Ken Carr, writes:

I’m not sure if my radio is a ‘benchmark’ but it sure is close to it.
It is the E. H. Scott Philharmonic Beam of Light console radio.

Mine appears to have been built in 1939 or early 1940. It has 30 tubes, most of which are covered by chrome-plated shields. The power supply/amplifier (4 6L6’s in the output stage), receiver, 15″ speaker and cabinet easily weigh over 150 pounds.

It took me two years of occasional work (I am retired so I don’t rush) to get it going and working reasonably well. I had to replace over 100 capacitors and correct some B+ voltage problems left by a previous repair person.

None of the knobs are correct (mine came without them … 9 required) and replacements are difficult to come by (and quite expensive when they do appear).

When receiving a strong station the volume is such that it would easily drown out anything within 100 yards (and with no distortion).

Some day I will post some details and photos on my WordPress site (idlenot.com). I’ll be sure to let you know, Thomas. [Note: Yes, Ken, please do!]

Oh, the first time I powered it up and received a station they were playing Light My Fire (The Doors, I think). Appropriate. I put a video of it on YouTube. The radio is all apart as I was still working on it at the time.

Click here to view on YouTube.

Now that is serendipity, Ken–I mean, the first music you hear after restoring this beauty is Light My Fire? Brilliant!

The E. H. Scott Philharmonic Beam of Light is a benchmark console by any standard. I first learned about this radio through a local classified ad–the owner was selling the internal components (and original knobs) but had no cabinet. I believe he was asking $1200. The chrome plating is such eye candy, I can see why some owner in the past removed it from the cabinet to save space. Still, it was a shame the cabinet had been discarded–as one can see from your photos, the craftsmanship is simply stunning.

Ken, thank you for taking the time to share the Beam of Light console with us!

Post readers: you should check out Ken’s blog, Idlenot.com, where you’ll find more vintage radio and classic cars!

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Guest Post: Building a magnetic loop antenna & broadband amplifier for your SDR

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Many thanks to SWLing Post contributor, Dave Gahimer (K9ZCE) for the following guest post:

Small Magnetic Loop Antenna with Broadband Amplifier for SDR Reception

by Dave Gahimer (K9ZCE)

Those with limited space, or antenna restrictions, might find a small 1 meter loop antenna a solution.

My son lives in an apartment. One Loop leaning against a wall gives him acceptable reception with the SDRPlay RSP on the ground floor–2nd or 3rd level flats should have very good reception.

Ten meters off the ground outside should give reception equal to any SWL antenna. We all with SDRs fight the image problem. Normal resonate ham band antennas show too strong reception of unwanted bands/stations. Did I mention noise? Loops are well known for –6 db noise reduction.

Then there is the possibility of SDR chip damage from your 1.5 KW station! In researching Loops we came across LZ1AQ. A Brilliant design /engineer (http://www.lz1aq.signacor.com/). Deep reading sometimes, but a great understanding of what makes a good receiving loop antenna.

Those who chase DX know that sometimes fading is caused by the signals’ polarization changing in the Ionosphere. Having both vertical and horizontal loops, and the ability to combine both signals diminishes this fading problem. Being able to filter the powerful, commercial FM transmitters diminishes image problems. Clipping strong signals at the antenna from very near powerful antennas/transmitters could save the SDR receiver from damage.

The LZ1AQ broad band Amp solves all these problems. http://active-antenna.eu/amplifier-kit/.

My son Ted and I built three, one meter loops from soft ½ inch copper plumbing tubing. One for his apartment, two for my crossed loops antenna. We weather proofed the Copper from corrosion by coating with outdoor clear spar varnish. We shaped the circle by drawing the tubing around a round glass top patio table.

The soft copper loop in held by white PCV plastic plumbing pipe. 1” or 1.25 inch schedule 40. Be careful to check that the PVC is schedule 40, thick wall. The thin wall pipe is not strong in the wind and will crack when you try to drill it.

Drill up to a 3/8 hole for the ½” copper tube to go through, then file out to fit. Here are some photos (click to enlarge):

Check out these links (all courtesy of LZ1AQ) to acquaint yourself with the loop construction and amplifier installation:

http://active-antenna.eu/tech-docs/2_ActiveAA_Mount_20.pdf

http://active-antenna.eu/tech-docs/1_ActiveAA_DandS_20.pdf

http://active-antenna.eu/tech-docs/3_ActiveAA_Antena_11.pdf

Many SDR receiver owners have seen improved noise and Image reduction by placing the plastic cased SDR unit on a small shielded/ grounded case.

The Amp needs 12VDC from in the shack. The Amp has two relays that you can switch, from in the shack, to select Vertical or Horizontal loops, or a dipole. The loop amp connects back to the shack via a shielded Cat 5 cable, Make sure you get shielded CAT 5 to reduce noise pickup. Make sure you provide an adequate good Ground below the antenna, less noise pickup and lightening protection.

Have fun!
Dave, K9ZCE
Retired from EE Dept @ Rose-Hulman Institute of Technology
Terre Haute, Indiana

Thank you so much, Dave!

Readers: yesterday I saw Dave’s loop antenna photos on the SDRplay RSP Facebook page. I was fascinated by his horizontally/vertically oriented loops and asked if he would write up a short guest post. He kindly obliged in a matter of hours!

If you have an antenna project you’d like to share, please contact me. So many SWLs and ham radio operators live in areas with restrictions and pervasive RFI–projects like Dave’s can revive one’s radio life!

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Radio Prague: Underground agents and plots in the Cold War broadcasting war

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Many thanks to several SWLing Post readers who shared the following story from Radio Prague:

Underground agents and plots in the Cold War broadcasting war

In this week’s Czech History we look at one aspect of the Cold War, the use of secret agents to spy on and disrupt the enemy’s propaganda services. In particular, we focus on the circus that surrounded the return of a Czechoslovak double agent Pavel Mina?ík 40 years ago in 1976 which was aimed at discrediting the US financed and Munich-based broadcaster Radio Free Europe.

Click here to read the full article and listen to the radio documentary on Radio Prague’s website.

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Paul Litwinovich on “The Life, Decline and Possible Rebirth of AM”

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Many thanks to the SWLing Post reader who noted this latest post by Paul Litwinovich at WSHU (Paul is frequently referenced here on the Post).

A short excerpt:

“AM occurs elsewhere in nature. A lightning strike or manmade electrical discharge will produce a burst of electrical noise that varies in amplitude. Since AM radios are designed to detect variations in amplitude, this is why they are prone to interference from such things. AM held sway as the primary method of modulating a radio wave up to WWII, not only for broadcasting, but for all types of radio communications.

Every vintage consumer radio, be it standard broadcast or shortwave, up to WWII, received amplitude modulated signals. Nowadays, AM broadcast stations are associated with lower quality audio, but such was not always the case. Receiver design really came of age in the 1930s with the superheterodyne circuit and advancements in loudspeaker design. The grand floor consoles of the late 1930s leading up to WWII were capable of producing audio that was very good, even by today’s standards, the only exception being that they were monaural, as stereo technology was still a ways off.”[…]

Litwinovich’s article is a must-read as he gives a concise overview of amplitude modulation, AM vs. FM, and even covers current proposed uses of the broadcast band (something we’ve also recently mentioned).

Click here to read The Life, Decline and Possible Rebirth of AM.

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Radio World: Schenectady Shortwave Transmitters, 1941

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Many thanks to SWLing Post contributor, Dan Robinson, for sharing a link to the following article in Radio World:

The General Electric Co. was truly among America’s premier broadcasting companies.

In addition to developing much of early broadcast technology and building a trio of high-power AM stations in the early 1920s — WGY Schenectady, N.Y.; KOA Denver; and KGO Oakland, Calif. — GE was also the country’s pioneer shortwave broadcaster.

GE’s initial shortwave station, 2XI, first broadcast in 1923, and in 1924 it was used to relay WGY’s programs for to KOA and KGO for rebroadcast in the western U.S.

By 1925, there were two experimentally licensed shortwave stations in Schenectady: W2XAD and W2XAF. A third GE station in San Francisco, W6XBE, was added in 1939.

That was the year that the Federal Communications Commission allowed the country’s experimental shortwave stations to relicense as commercial operations, and these three GE stations received the call signs WGEA, WGEO and KGEI, respectively.

Continue reading the full article at Radio World.

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Shortwave Numbers Stations on The Daily Beast

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Interest in shortwave numbers stations seems to wax and wane. We’re currently going through a period of increased interest (again) as I’ve been receiving quite a few messages from new readers asking where to find spy numbers and what type of shortwave radio is needed. Truth is, there are fewer and fewer numbers stations still on the air, though some are still quite reliable (like HM01).

The following article by Shane Harris at The Daily Beast is one of the better, more detailed, articles I’ve read in the popular press.

(Source: The Daily Beast via Southgate ARC)

The Stupidly Simple Spy Messages No Computer Could Decode

by Shane Harris

When I was 10 years old, I found a shortwave radio in a crumbling old leather trunk where we kept family photos and other memorabilia.

As I spun the dial, tinny, modulating noises, like the song of an electronic slide whistle, emanated from the radio’s small speaker. Staticky cracks and pops competed for airtime. The sounds swished and swirled, unintelligible and unremarkable. But then, emerging through the clamor, was a voice.

I might have run right over it with the dial, but the voice’s rhythmic, steady pacing caught me up short. It wasn’t a deejay. Nor a commercial. And he wasn’t singing. He was just speaking. The same line, over and over again.

“7…6…7…4…3.” Pause. “7…6…7…4…3.”

I don’t remember if those were the exact numbers. But they were numbers. A repeated sequence which had no obvious meaning, and was entirely devoid of context. To find him here, amidst the screeches and howls of the shortwave frequencies, was like coming upon a man standing in the middle of a forest, talking out loud to no one.

How long had he been here? Who was he talking to? He had that officious tone of the recorded telephone operators who chastised you for dialing a wrong number. “Please hang up, check the number, and dial again.” And the same distracting static I’d heard in those messages filled the background. I wasn’t sure if he was speaking live, or if he’d been recorded and set loose to play into the air.

But there was an urgency to his tone. And a purpose. As if he were talking to me. Imploring. Listen. Hear me now. 7…6…7…4…3. Did you get that? 7…6…7…4…3.

I was simultaneously terrified and captivated.[…]

Continue reading at The Daily Beast…

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The Heathkit GR-78: Ed’s “basket case” radio

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Many thanks to SWLing Post reader, Edward Ganshirt, who writes:

I picked up this Heathkit GR-78 at a estate/moving sale. It was in a pile of “e-waste” (you know, old vcr’s broken TVs, remote controllers, dead cell phones, etc.).

I found a container and sorted through the stuff to retrieve all what looks like Heathkit parts. The radio was disassembled and scattered about. I was able to collect all the critical components and brought the works to the sales table. The person manning the table said that was stuff they were discarding and I could have it for free but the Easter basket was $0.50.

So far I had put little time into it but was able to mechanically assemble it completely. All the fasteners holding the cabinet were missing. The rest appears to be all there but the primary side of the transformer is open and the NiCads are shorted and stone dead. The manual that I found in their recycle bin is complete and appears to gone through 3 owners by 3 sets of handwriting in the notes and comments through out the manual. If anything this looks like a CSI/forensics troubleshooting process getting into the mind of 3 different owners unsuccessful at making it work.

I will keep you posted on the progress.

WA1-LAI

More power to you, Ed! There are few things as difficult as picking up where someone else left off on a kit build. Your project is exponentially more complicated since there were three people involved and parts are scattered. Please update us with your progress.

Readers: If you have any experience with the GR-78, I’m sure Ed would welcome your input!

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