1957 Rohde & Schwarz EK07 D [RADIO]
(Acquired from Albert Sloot in Vroomshoop, NL) Listening to a EK07-D shortwave radio made by Rohde and Schwarz. Back then the price was around 12.000 DM. Today very few people need a 65kg shortwave radio so it's mainly the willingness to carry one inside (and the patience to find one) that gets one. Listening to short radio waves can be very educational.
From Fred Osterman's catalog "Shortwave Receivers Past & Present 4th Edition Communications Receivers 1942--2013":
PS
A friend asks me "can you explain what you're doing with these radios and why you do it?"
Quality
Part of the fascination, for me, is the extreme quality of these huge devices. How they were built to be at the very cutting edge of technology in their time without any regard to what it would cost. Every country's army needed a stack of receivers to listen to any signal they could possibly pick up from friends and foes and the receiver needed to be as stable as possible, so one would be listening to the same exact frequency and not worry that the room full of radios had been quietly drifting into different channels.
The old radio, when properly serviced (faulty capacitors replaced, some valves replaced, circuitry tuned) is ready for another generation of listening and it can be a century old while still working, whereas today's new devices could be obsolete in 15 years, for instance if the computer display is no longer in stock.
Boatanchor
The no-compromise way of design and build created these heavy receivers that some in the radio world fondly call "boatanchors".
Sound
These devices were so well built that they can still compete against the best of the best available in present day technology. Sure, a super duper digital computerized receiver weighs a fraction of its massive granddad, but the vintage radio can present a sound that's impressively calm compared to the digital receiver's sound which is bright, sharp and more tiresome to listen to.
Stations
Listening to the shortwaves, I noticed that the Dutch national broadcast organisations have left these frequencies but luckily the BBC is still present with programs of journalists and other guests in the studio having polite conversations about the news and other subjects. And then there are fascinating stations sponsored by the Chinese and Romanian governments who offer music, cultural news from their capitals, radio drama in perfect British and American accents and propaganda, politely informing the world about the superior character of the Chinese people. On the modern radio I hear the Air Traffic Control exchanging a constant flow of directives and confirmations between controllers and pilots, all calm, concise, to the point with just one word of greeting added to acknowledge a shared nationality.
Insomnia
An then there are the amateurs, the HAMs. Mostly old people in their radio shack, a room upstairs or a barn outside the house, in a place where the family lets them be since "to be happy a man needs to be very very close to someone who leaves him alone".
Some listen, some talk. I very rarely hear a young person active with a transmitter so I assume this radio society is slowly disappearing and I'm listening to the last conversations of old men who can't sleep at night and who're happy to chat with their radio pals about anything that comes to mind. Memories of their time in the army, what beer they anjoy drinking lately, how much they miss their dear ones who already passed away. Irish guys, Germans, a Belgian now and then. Russians frequently, reaching out. A man in Stuttgart testing out his new antenna to see if he can talk with anyone in the USA. Someone in Riga waiting for a response to his callsign.
Interference
The best time to listen is very late at night, when the sun is gone and solar activity is not blasting away the weak communication signals. Also, during the day many devices in the crowded city radiate a screeching mess. My own coffee roaster, when active, makes it impossible to receive short wave radio sounds. Solar panels and air conditioners are radio signal destroyers as well.
Sitting in front of my receivers is therefore almost like fishing. One can sit there and get nothing, or all of a sudden, because somewhere some machines are switched off, somewhere else transmitters are turned on, reflections in the atmosphere bounce transmissions over very long distances, and voices can be heard while the sharp crackle of interference quiets down around them.
Silence
Someday it will all be quiet and empty with just the noise and squawk from encoded digital communication of computers chatting with each other.
But for now, I enjoy the meditative routine of browsing the frequencies, listening for brief flashes of voice, watching on screen for the dial indicating a burst of electromagnetic energy that might, after some tweaking and filtering, reveal human communication.
Youtube version: https://youtu.be/zWnBAWkKvQw
From Fred Osterman's catalog "Shortwave Receivers Past & Present 4th Edition Communications Receivers 1942--2013":
Lothar Rohde and Hermann Schwarz met in 1929 as college physics students at the Physical-Technical Institute in Jena, Germany. After graduation they built a precision frequency meter for wavelengths of 6 to 3600 meters and published an article on it in Hochfrequenztechnik und Elektroakustik in 1932. In 1933 they moved to Munich and established the Physikalisch-Technisches Entwicklungslabor Dr. Rohde & Dr. Schwarz (PTE). Through difficult and transitional times the company continued and enjoyed explosive growth after 1953.Rohde & Schwarz became best known to the listening community with the development (1953-1955) of the famous (and huge!) EK07 general coverage receiver. This, the "Collins R-390" of Germany, was of the highest technology of the time and offered frequency accuracy and performance that was to be the standard for nearly twenty years. (...) Incredible craftsmanship is evident in this classic receiver. The meter on the left checks performance of each tube. Last production for German secret service had LED display for fine readout. EK07/D refers to German version. Extremely scarce.Today Rohde & Schwarz is engaged in the development, manufacturing and marketing of professional radio communication products. It provides system solutions in the fields of global communications, ATC and airport communications, avionics and naval communications. It is a leading supplier of solutions in the fields of test and measurement, broadcasting, radio monitoring and radiolocation, as well as secure communications. The company has a presence in over 70 countries.
From a publication by Rohde & Schwarz:
I currently feed antenna signal into the back on two points: one wire antenna in the "High Impedance" socket and one cable which had a BNC that I replaced with two banana plugs.
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| The socket for which I had no fitting connector |
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| In a Rohde & Schwarz publication, it's like the one on the left |
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| Looks like they call it an N-Type |
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| My solution for now |
 | |
| Fits well
I asked Rohde & Schwarz' customer support and they replied:
|
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| The radio found its place |
 |
| Front view |
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| Rohde & Schwarz EK07 connectors |
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| Rohde & Schwarz EK07 connectors |
PS
A friend asks me "can you explain what you're doing with these radios and why you do it?"
Quality
Part of the fascination, for me, is the extreme quality of these huge devices. How they were built to be at the very cutting edge of technology in their time without any regard to what it would cost. Every country's army needed a stack of receivers to listen to any signal they could possibly pick up from friends and foes and the receiver needed to be as stable as possible, so one would be listening to the same exact frequency and not worry that the room full of radios had been quietly drifting into different channels.
The old radio, when properly serviced (faulty capacitors replaced, some valves replaced, circuitry tuned) is ready for another generation of listening and it can be a century old while still working, whereas today's new devices could be obsolete in 15 years, for instance if the computer display is no longer in stock.
Boatanchor
The no-compromise way of design and build created these heavy receivers that some in the radio world fondly call "boatanchors".
Sound
These devices were so well built that they can still compete against the best of the best available in present day technology. Sure, a super duper digital computerized receiver weighs a fraction of its massive granddad, but the vintage radio can present a sound that's impressively calm compared to the digital receiver's sound which is bright, sharp and more tiresome to listen to.
Stations
Listening to the shortwaves, I noticed that the Dutch national broadcast organisations have left these frequencies but luckily the BBC is still present with programs of journalists and other guests in the studio having polite conversations about the news and other subjects. And then there are fascinating stations sponsored by the Chinese and Romanian governments who offer music, cultural news from their capitals, radio drama in perfect British and American accents and propaganda, politely informing the world about the superior character of the Chinese people. On the modern radio I hear the Air Traffic Control exchanging a constant flow of directives and confirmations between controllers and pilots, all calm, concise, to the point with just one word of greeting added to acknowledge a shared nationality.
Insomnia
An then there are the amateurs, the HAMs. Mostly old people in their radio shack, a room upstairs or a barn outside the house, in a place where the family lets them be since "to be happy a man needs to be very very close to someone who leaves him alone".
Some listen, some talk. I very rarely hear a young person active with a transmitter so I assume this radio society is slowly disappearing and I'm listening to the last conversations of old men who can't sleep at night and who're happy to chat with their radio pals about anything that comes to mind. Memories of their time in the army, what beer they anjoy drinking lately, how much they miss their dear ones who already passed away. Irish guys, Germans, a Belgian now and then. Russians frequently, reaching out. A man in Stuttgart testing out his new antenna to see if he can talk with anyone in the USA. Someone in Riga waiting for a response to his callsign.
Interference
The best time to listen is very late at night, when the sun is gone and solar activity is not blasting away the weak communication signals. Also, during the day many devices in the crowded city radiate a screeching mess. My own coffee roaster, when active, makes it impossible to receive short wave radio sounds. Solar panels and air conditioners are radio signal destroyers as well.
Sitting in front of my receivers is therefore almost like fishing. One can sit there and get nothing, or all of a sudden, because somewhere some machines are switched off, somewhere else transmitters are turned on, reflections in the atmosphere bounce transmissions over very long distances, and voices can be heard while the sharp crackle of interference quiets down around them.
Silence
Someday it will all be quiet and empty with just the noise and squawk from encoded digital communication of computers chatting with each other.
But for now, I enjoy the meditative routine of browsing the frequencies, listening for brief flashes of voice, watching on screen for the dial indicating a burst of electromagnetic energy that might, after some tweaking and filtering, reveal human communication.
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