Due to their small size and low power consumption, transistors quickly found their way into new applications such as radars and computers. In the field of audio, the first applications were car and portable radios. The world’s first “fully transistorized” radios were seen in the mid-1950s. The very first was probably the Regency TR-1 from 1954.

When mass production of transistors began in earnest, the supply of radios increased almost exponentially. Grundig, Telefunken, Braun, etc. in Germany; Philco, Zenith, GE, RCA, etc. in the USA; Sony, Toshiba, Matsushita, Sanyo, etc. in Japan churned out small portable radios. Many of these brands quickly landed in other countries worldwide.

In Finland, the Russian Selena brand radio sold well. The Finnish Salora and ASA also manufactured radios. ASA’s first transistor travel radio was the 155 TM from 1959. Since transistors that worked on VHF frequencies did not yet exist, the 155TM was an AM receiver. The 155 TM hid seven OC series Germanium transistors.

Portable transistor radios are traditional heterodyne receivers in structure. The signal is first mixed to an intermediate frequency, where it is amplified, and the power of other channels is filtered out before being mixed into the base frequency. There are usually five to fifteen transistors (mainly in the RF and audio amplifier section). Transistors were more than just a new technology: many early portable radios proudly stated how many power transistors are inside the device (usually from 5 to 15).

For this article, five portable transistor radios from the 1960s and 70s were ‘tested’. The radios were obtained from Olavi Korkia-aho’s extensive collection. All radios have an FM or VHF receiver. The sound quality and station reception of radios are assessed using the PAL index. The PAL index is a percentage that indicates the level of the device in relation to a modern portable PAL radio by Tivoli Audio (= 100). Sound quality mainly refers to the balance of the sound, and the purity of the sound (the quality of the speaker element).

Telefunken Bajazzo TS 201

Telefunken’s Bajazzo TS 201 was apparently manufactured in West Germany in the late 1960s. There are three other versions of the once popular radio: TS 101, TS 201 Deluxe and Sport. The TS 201’s casing is made of hardboard covered with plastic veneer. The front panel grille is made of chrome-plated plastic. The leather-covered, metal carrying handle is swivel, which makes tuning easier. The radio is quite large and weighs 3.2 kg – not something to carry for long distances. Inside there are 11 x AF106 transistors (Germanium MESA PNP). The radio sports a 13 x 18 cm elliptical driver. There are five wavebands: LW (148 – 350 kHz), MW (515 – 1630 kHz), KW (5.94 – 15.6 mHz), Europa band (1415 – 1620 kHz) and FM or UKW (87.5 – 104 mHz). For FM, there is a separate tuning knob, as well as for AFC (Automatic Frequency Control). A metric telescopic antenna for FM and short waves, an internal antenna for medium and long waves. On the side, there is a DIN connection for a tape recorder and some kind of adjustment screw for it. There is also a plug connector for an additional speaker and two inputs for separate antennas. The TS 201 only runs on batteries, but can be connected to a car’s 12 V DC power supply.

Verdict: The radio tunes extremely well, and there are no complaints about the reception. The sound is healthy and fairly well balanced, wide and expansive. The driver size is a positive factor. Nevertheless, the sound balance suffers from a lack of bass, but it is not equally disturbing with all music. Separate tone controls for treble and bass are not of much use. Speech is reproduced surprisingly well and naturally. At its best, the radio brings genuine listening pleasure to music.

PAL index: audibility = 85, sound quality = 80.

Golf 220 International

The American ITT expanded in the 1960s through numerous aggressive acquisitions. This gave ITT a solid foothold in the home electronics market in Europe as well. The ITT GOLF 220 International was manufactured by ITT’s German branch ITT-Graetz in the late 1970s, possibly early 1980s. The radio is made entirely of plastic, including the handle. As a result, it weighs no more than one and a half kilograms. The telescopic antenna is about a meter long. According to one source, there are 9 transistors inside, but the information is not certain. There are apparently two speaker drivers, with a power rating of 7 W. There are six wavebands: MW (515-1600 kHz), LW (270-150 kHz), SW1-SW3 (2.3-18 mHz) and FM (86-108 mHz). The readings on the display are from right to left. There is a meter for FM and AM broadcasts that shows the signal strength. There is also a tone control, as well as recorder and headphone connections. The radio runs on both mains power and batteries.

Verdict: Stations tune in reasonably well and the range is good, with moderate interference levels. The sound is fairly big in size and lively, and the balance of the sound cannot be particularly faulted. However, there is some dullness – mediocrity – in the sound, and perhaps a little more bass than on average, but the playback range is still limited. The tone control is not as sharp as on other radios.

PAL index: audibility = 80, sound quality = 60

Philco PT 914 ITT

The American Philco, founded in 1906, was once a mega-class radio manufacturer. In the 1940s, Philco began manufacturing its own vacuum tubes for its radios. Transistors were manufactured in the same factory in the early 1950s. In 1955, Philco introduced a fully transistorized record player with an amplifier and a year later began manufacturing transistorized car radios. The Philco PT 914 dates back to the late 1950s or early 1960s, and may well be the oldest of the experiments. The front panel is made of real metal, the rest of the casing is made of leather-covered hardboard. The front panel has five rotary switches: tuning, fine tuning, waveband selector, tone control and volume/on-off, as well as a small lever for AFC. There are six wavebands, three for shortwave (SW 1.7-4.2, 4.0-10.0 and 10-18 mHz) as well as LW, AM and FM. The metal carrying handle is modest, the half-meter telescopic antenna does not fold to the side. Connections for headphones and a 9-volt adapter exist. The device possess 6 Philco’s own Germanium transistors. There is no information about the speaker driver, but it cannot be much more than four inches.

Verdict: The radio tunes well and the range is moderate. The sound is dry and limited in bass, and not very big. The tone control to increase bass does not improve the situation in terms of sound balance. However, the sound has its own merits, and it lacks the typical ‘portable radio-likeness’ quality. Classical music is reproduced well from time to time, and speech is muffled.

PAL index: audibility = 75, sound quality = 70.

Craftsman Model 9333

This is apparently from the same Radio Craftsman Company that was founded in 1949, and known for its famous C 500 series tube amplifiers (designer Sid Smith later had a spectacular career with Marantz). After the company closed in 1956, the Craftsman name has apparently been passed down as a brand name from owner to owner. This device was built in Japan, possibly in the mid-1970s. The body is leather-covered hardboard. It sports a strong, solid metal carrying handle. As a portable radio, the machine weighs quite a bit. The front panel says “Solid State”, but there is no information about the number of transistors. The four-inch driver is Japanese-made. On the side are plug connections for an additional speaker and headphones. There are five bands: AM (530-1600 kHz), MB (1.6-4 mHz), SW (4.5– 12 mHz), FM (86-108 mHz) and VHF-PB (108-174 mHz) and they are named as follows: Sport, Marine, Foreign, Music and Air&Police. There is a small light button on the front to make tuning easier in the dark. The antenna is a nearly one and a half meter telescope. The radio works both on mains power and on batteries.

Verdict: The radio tunes fairly accurately and the stations are well received. The sound is not particularly unbalanced, but the band is limited. The H-L tone control only attenuates the mid and upper mid range rather than adding bass. The small driver reproduces a loud and nasal sound. It cannot withstand loud listening.

PAL index: range = 70, sound quality = 55

Matsushita T-30

There is little information about this Japanese “All Transistor” travel radio. The back cover reads T-30 and Matsushita Electric Industrial Co. Matsushita, or National, as the company is also known, is what later became an international electronics giant. Its brands today include Technics, JVC and Panasonic. The stylish T-30 is the smallest and most portable travel radio of this group. It weighs less than a 1 kg. The golden casing is made of pure plastic, not Bakelite. The carrying handle is attached to the cover with loops, from which rises a telescopic antenna of about half a meter. The probable date of manufacture is the early 1960s. The radio can only receive AM and FM stations. The number of transistors is unknown. The sound comes from a five-inch dynamic driver. The radio only runs on batteries. There is a headphone and speaker connection as well as inputs for three separate antennas. Unfortunately, at the crucial moment, the radio refused to emit anything but a hissing sound. Hence, no scores.

Verdict: –

The winner

So the winner of the test was Telefunken Bajazzo TS 201 made in West-Germany probably at the end of the 1960s. As a fairly big and heavy device, it is not for long walks. But it tunes surprisingly well, and the tone quality was healthy and balanced, only suffering, as one would expect, from insufficient bass. Speech is reproduced quite naturally, and at best even music is coming out nicely, not lagging much behind Tivoli PAL. All in all, it turned out that portable radios of the 50s and 60s are still very much listenable units, and visually, of course, a way ahead of the modern gigs.