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Zenith 1000-D
Portable short-wave receiver

The Royal 1000 Trans-Oceanic was a portable solid-state LW, MW, and SW receiver (150 kHz - 22 MHz), also known as a world receiver, manufactured by Zenith in Chicago (Illinois, USA) and introduced in 1957, at a time when transistors were a real novelty, and valve-based receivers were still being manufactured at much lower cost. The price of the 1000 at its introduction was US$ 275 [1]. Newer versions, like the 1000-1 and 1000-D were introduced during the 1960s.
The radio measures 320 x 267 x 122 mm. The desired frequency band is selected with a rotary knob at the right side, that controls the rotating drum scale on the left. The drum scale can be illuminated by pressing the Light-button. The radio has in internal ferrite antenna (here called a Wavemagnet), plus an external one that is stored in the battery compartment at the rear. In addition it also has a telescopic antenna that is hidden inside the carrying handle at the top.

The radio is powered by nine 1.5V D-cells and there is no provision for an external mains PSU.

The Zenith 1000 radios were very popular with Radio Amateurs and SW-listeners, but also with the international spy-scene of the late 1950s and early 1960s as it offered a good alternative for the bulky and heavy spy radio receivers of the era. In many cases, East German spies, operating in West Europe or elsewhere, used the Zenith 1000 for receiving messages from their headquarters.
A good example of the use of the Zenith 1000 in Cold War espionage, is its deployment by the Czechoslovakian intelligence agency in Congo in 1960, where it was used in combination with a 50W long-range SW transmitter. As the receiver was available off-the-shelf, buying one would not attract any attention and it gave them free access to the latest technology from the West.

As the scale of the Zenith 1000 is not accurate enough for this application, the crystal-based transmitter would generally be used to 'calibrate' the receiver and tune it to the desired frequency.
Zenith 1000-D as part of a spy radio station in 1960. Click for more information.

Radio amateurs and SW-listeners will probably remember the mysterious number stations on the SW bands throughout most of the Cold War. A female voice that was reading endless sequences of seemingly random numbers for 24 hours a day, often in Russian, Spanish or German:

Funf, drei, sieben, acht, vier, trennung...

Many such number stations were operated by the secret services of Eastern Block countries, such as Russia (USSR), East Germany (DDR), Hungary, Czechoslovakia and Romania. The numbers were actually coded messages for their secret agents and spies that operated undercover in the West. Commercial receivers like the Zenith 1000 were often used for the reception of such messages.

Although the first all-transistor radio appeared on the market in 1954, the Royal 1000 was the first all-transistor general-coverage portable LW, MW, SW radio, with the Royal 1000-D version adding the LW band in 1961. Despite its high price of US$275 (1957), 165,000 units were sold before it was succeeded by the Royal 3000 in 1963 [2]. The radios are now difficult to find.
Zenith 100D with closed front panel World-wide time zones Operating instructions Audio controls and headphones socket Tuning Unlocking the telescopic antenna Telescopic antenna in carrying handle

The interior of the Zenith 1000 can be accessed through the hinged door at the rear. It can be opened by lifting the lock through the hole at the back. The battery compartment, at the bottom right, takes nine 1.5V D-type cells. Fitted above the battery box is the external ferrite antenna.
Part of the electronics is visible at the left half. It consists of a chassis with coils and socketed transistors, all wired at the back of the chassis, much like with the valve-based radios of the era.

The overall build quality is very good and it is known that the entire chassis was hand-wired, which probably accounts for the high cost of the radio. The performance on the SW-bands is excellent, and for a long time the Zenith 1000 belonged to the best domestic SW receivers on the market, until it was outperformed by the Sony ICF-2001 and the Grundig Satellit 2000.

The full service manual with circuit diagram is available for download below [A].
Rear view Opening the rear cover Interior Battery box battery connection Built-in ferrite antenna Removing the external ferrite antenna Using the external ferrite antenna

Frequency ranges
  • Broadcast
    55-160 m
  • Weather, Marine & Amateur
    2-4 MHz
  • Weather, Marine & Amateur
    4-9 MHz
  • Afternoon & Evening
    9.4-10.1 MHz (31 m)
  • Afternoon & Evening
    11.4-12.3 MHz (25 m)
  • All day
    14.6-15.8 MHz (19 m)
  • All day
    17.2-18.4 (16 m)
  • All day
    20.7-22.5 (13 m)
  • 121-44
    RF Amplifier (NTE126)
  • 121-48
    Oscillator (NTE160)
  • 121-49
    Mixer (NTE160)
  • 121-49
    IF1 (NTE160)
  • 121-181
    IF2 (NTE160)
  • 121-64
    AF1 (NTE102A)
  • 121-46
    Driver (NTE102A)
  • 121-47
    (2x) AF Amplifier (NTE102A)
  1. Zenith, Service Manual Model 'Royal 1000', Chassis 9CT40Z2
    Zenith Corporation. Date unknown. Retrieved August 2015.

  2. Zenith Royal 1000D circuit diagram
    Zenith Corporation. Date unknown. Retrieved August 2015 [3].

  1. Philip I. Nelson, Zenith Model 1000 TransOceanic Radio (1957)
    Website. Retrieved August 2015.

  2. Konrad J. Birkner, The Zenith 'Trans-Oceanic'
    Website Radiomuseum. Retrieved August 2015.

  3. KE9NS, Zenith TansOceanic (transistor and Tube type)
    Retrieved August 2015.

Further information

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Crypto Museum. Created: Tuesday 11 August 2015. Last changed: Wednesday, 07 September 2016 - 06:34 CET.
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