German vacuum tube radios

I started collecting German radio sets for their accurate design, resulting in reliable operation and in a remarkable sound reproduction. The quality of German sets can be better appreciated when compared with similar sets built in Italy in the same days. Most of the Italian productions had no power transformer, the chassis being connected to the mains, no built-in antenna, no tone controls, no multiple speaker system. On the contrary, German radios were fine examples of engineering with a lot of interesting solution, including:

Ø Low-profile chassis, with expanded tuning dials.

Ø Power transformer with insulated chassis, plus high-efficiency Graetz-bridge selenium rectifier.

Ø Internal AM/FM antennas, usually with AM rotary loopstick.

Ø Keyboard band/function switch.

Ø Smooth tuning systems with reduction gears and flywheels. Dual coaxial knobs for AM and FM or single knob mechanically driven by band switching keys. Preset channels, band spread dials. Motor-driven auto tuning in some models.

Ø Loudness control plus tone controls and even tone registers, sometimes in addition to IF variable bandwidth, driven by the same tone control knobs.

Ø Speaker systems including electrostatic or horn tweeters.

When I started the collection, AM broadcast stations were already in progress of being dismantled. I focused then on FM radio sets, which could still be enjoyed today. The drawback for most of German sets is the poor FM coverage, limited to 100 MHz. Exhibits include radio sets from the very early introduction of FM, around 1950, to the late FM-Stereo vacuum tube radios, dated around the mid sixties. It is very interesting to compare through the years the evolution of the audio section, amplifier and speaker system, according to the evolution of sound sources.

Actually the very early FM sets were just AM radios with added FM tuner. Program sources at the time were the old standard-groove shellac records. The design of audio amplifiers and speakers was still centered around 5 kHz bandwidth. With the introduction of microgroove vinyl records, the bandwidth quickly jumped to about 15 kHz. Speaker systems started then to include tweeters. The early low efficiency electrostatic types were soon replaced by dynamic cones and even by horn drivers.

The early approach to stereophony, around 1957, was a 3D surrounding sound, with extra speakers added on both sides, all driven by the same monophonic source. Later, even if the tuner was still mono, audio section evolved with provision for full dual-channel amplifier. Stereo sound was possible listening to stereo records, or even to stereo tape sources.

We have to wait until the mid sixties to see full stereophonic sets with FM stereo decoder. First, when the service was still experimental in very few big cities, we find a simple socket for optional stereo decoder, then the decoder was factory installed. Most of these new sets, known as ‘steuergërat’, came with external speakers, according to the standards introduced by American Hi-Fi sets. But the Japanese industry was already moving to full solid-state. After few hybrid solutions, German vacuum tube radios disappeared from the scene.

The collection well shows the evolution through some fifteen years, from about 1950 to about 1965, with a wide overview of models mainly from Graetz and Saba, but also from AEG, Blaupunkt, Braun, Grundig, Telefunken and others even from other countries. The exhibits are divided into three major groups:

Graetz German radios, about 1950 to 1965.

Graetz was a typical German radio manufacturer. The collection includes several FM vacuum tube models, from 1950 to about 1965, offering a quite complete overview of the technical improvements through the years.

Model	Year(s)	Notes
154W	1950 / 1951	Rimlock tubes, electrodynamic speaker, 2 x EF42s in FM tuner.
Gross-Super 156W	1951 / 1952	Rimlock tubes, electrodynamic speaker, 2 x EF42s in FM tuner. EL11 output amplifier, 6W.
176W	1953 / 1954	10 tubes, EL84 push-pull audio amplifier, 3 speakers. Power save switch.
Melodia M518	1956 / 1958	4 loudspeakers, with 2-way flute compressor.
Sinfonia 522	1957 / 1959	EL84 audio amplifier, 2 woofers, 1 mid-range and one 2-way flute compressor.
Fantasia 1022	1961 / 1962	Stereo AF amplifier, 2x7.5W push-pull stages based upon EL95 power tubes. 6 speakers.
Fantasia 1318L	1964 / 1965	Solid-state stereo decoder, stereo push-pull amplifier with 2 x ECLL800, 2 speakers.
Musica 1316L	1964 / 1965	Solid-state stereo decoder, stereo amplifier with a single ELL80, 2 speakers.

Saba German radios, about 1952 to 1962.

Saba was well known worldwide for its top production.

Model	Year(s)	Notes
Meersburg W II	1952 / 1953	EL34 audio amplifier, two speakers. Variable IF bandpass.
Bodensee W3	1953 / 1954	12W audio amplifier w/ EL12, two speakers.
Meersburg W4	1954 / 1955	EL84 audio amplifier, 2 speakers.
Villingen W6	1955 / 1956	Low-end model, EL41 audio amplifier, single speaker.
Meersburg Automatic 7	1956 / 1957	10 tubes, auto-tuning, 4 speakers.
Phono-Super 8	1957 / 1958	Build-in record player, EL84 amplifier.
Freudenstadt 125 Stereo	1960 / 1961	Stereo amplifier, 2 x EL95, switched in push-pull like circuit when mono.
Meersburg Automatic 125 Stereo	1960 / 1961	Auto-tuning, stereo amplifier, 2 x ECL86
Meersburg Automatic 11 Stereo	1961 / 1962	Auto-tuning, stereo amplifier, 2 x ECL86

More German brands

Brand	Model	Year(s)	Notes
AEG	4075WD	1955 / 1956	SW band spread, EL84 audio ampl, 3 speakers
Blaupunkt	Virginia 2430	1957 / 1958	EL84 audio amplifier, 3 speakers
	Riviera 2540	1958 / 1959	SW band spread, 3 speakers, push-pull EL95.
Braun	99 UKW	1956	Four bands, UKW, 7 tubes
	TS31 Stereo	1961	Four bands, 9 tubes plus selenium rect.
Grundig	4040W	1953	Variable bandpass. 2, electrostatic and dynamic, speakers, EL12 audio amplifier.
	3055WF/3D	1955 / 1956	5 speakers, EL84 amplifier, remote control.
	3060a	1956 / 1957	Graphic equalizer, 4 speakers, EL84 amplifier.
	Steuergerät 6199	1960 / 1961	Stereo push-pull amplifier, 2 x ELL80, external speakers, graphic equalizer. Mono tuner.
	Phono-Kombi 2000Ph	1965 / 1966	3 tubes, AM/FM, PE record player
Kaiser	W1245-3D	1955 / 1956	3 speakers, EL84 amplifier.
Metz	belform Konzertgerät 120	1962 / 1963	Mono tuner, stereo amplifier, 2 speakers.
Nordmende	Stereo-Steuergerät 3004 5/634	1964 / 1965	Stereo decoder, 2 x ELL80 p/p amplifiers, external speakers.
Philips D	Saturn 641 Stereo B6D41A	1964 / 1966	Stereo decoder, 2 x ELL80 p/p amplifiers, 2 speakers.
Tekade	Melodie W387	1954	3 AM plus FM bands, 8 tubes
Telefunken	Hymnus 5014WK	1961 - 1962	Stereo amplifier, record changer, 2 x EL84 amplifier, 4 speakers.
	Opus 2340 Hi-Fi Opus Studio 2650	1963 - 1964 1965 - 1968	Vacuum tube and hybrid ‘Steuergerät’ with external speaker enclosures.