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Sony CRF-1

Manufactured by Sony Corp., Tokyo.

The CRF-1 was launched in 1981 as the successor to the large Sony portables CRF-320 / CRF-330K. Sony had also invested an enormous amount of development time in this set, but shortly afterwards technical development surpassed these innovations. Nevertheless, the CRF-1 was to remain the most technically perfect portable receiver for a long time. In terms of reception performance, it outclassed the portable sets from Panasonic just as much as the Grundig Satellit sets. I would like to compare it most closely with the SW-8 from Drake, which appeared much later. Both sets were overpriced in Switzerland and are much rarer here than in the USA. Sony CRF-1

Technical data

Power supply

Dimensions

  • 254 x 100 x 335 mm, weight 6.6 kg

Accessories

Sony CRF-1

Operation

The Sony CRF-1 is a portable top-of-the-range receiver that looks more like a tabletop receiver, if it weren't for the carrying handle and the long telescopic antenna. For operation, the receiver can be placed on the tilted carrying handle.

With its dimensions of 254 x 100 x 335 mm and its weight of 6.6 kg, the receiver is portable and a good companion for all those who travel by car on holiday and have enough space in the boot; for air travel, there are much lighter candidates from the same company.

The battery compartment, which holds 8 UM-1 mono cells under the top cover, also accommodates the power supply unit, which can be set to various mains voltages between 110 - 240 V and also provides the required 12 V operating voltage.

A coarse dial runs across the entire front panel, which, similar to the Philips D-2999, immediately shows the listener the actual position in the shortwave spectrum. Small marks indicate the shortwave broadcast and amateur radio bands. To the right is the small field strength meter, correctly calibrated in S-steps.

On the left side is the main switch, ergonomically next to it the double potentiometer for volume and RF gain control. Almost in the middle of the front panel is the LED frequency display, which indicates the frequency with an accuracy of 100 Hz. Unfortunately, the display brightness is quite modest, and the dark red LED display is extremely difficult to read when the unit is used outdoors.

The tuning knob is large and has a good grip, but setting the frequency on the receiver is a bit complex. With the knob pulled out, you quickly tune across the whole range, the tuning mechanism is fine enough to directly access radio stations in the 5 kHz grid. When you are close to an interesting frequency, push in the tuning knob and the set locks onto the next lower 100 kHz frequency mark. The fine-tuning VFO now tunes with steps of 100 Hz within this 100 kHz range, and the set does not show a musical scale effect even when in ECSS / SSB mode. Station search within a band is a bit difficult if a 100 kHz marker has to be crossed. Tune to 6 0 9 5 kHz - pull the knob - turn it a little further until it is above the 6,100 mark - push the knob in again and continue searching at 6 1 0 2 kHz.

To the right of the tuning knob below the S-meter is the equally important preselector knob. In the ranges 150 kHz - 400 kHz / 400 kHz - 4 MHz / 4 - 30 MHz you have to peak it to the signal maximum, the dial only gives an approximate impression of where to look for the signal maximum. The preselector dial of other sets, e.g. the ICF-6700W / 6800W, are much more useful. With a switch under the rotary knob, the preselector can be switched off in case of unproblematic strong signal conditions, which simplifies quick frequency changes. Right next to it is the switch for the noise blanker.

Finally, below the frequency display, there are pushbuttons to activate the dial lamp, to check the battery voltage and to activate the digital frequency display. Next to them are the operating mode buttons for AM - wide (10 kHz) / AM - narrow (4.4 kHz) / USB / LSB / CW (3 kHz).

Sony CRF-1On the rear of the set, there are jacks for line out, timer and muting, there are screw terminals for antenna and earth and a BNC antenna connector. With a rotary switch on the top of the receiver, the external antenna or the built-in telescopic antenna can be selected; for both antennas, a -20 dB attenuator is provided.

Technically, a signal fed to the external antenna connector first has to pass through one of the eight electronically switched octave bandpass filters, then the preselector, with its three sections, is switched into the signal path. In the first mixer, the signal is converted to the high first IF of 55.845 MHz; between the 100 kHz points, a VFO can be used to tune within the 100 kHz range; the signal is then converted to the second IF of the usual 455 kHz. After passing through the ceramic IF filter and IF amplifier stages, the signal is demodulated by a diode in AM mode, and a product detector is used for SSB mode.

In practical operation, the set was an excellent performer in the early 1980s and still can compete with many tabletop receivers today. If you are not absolutely dependent on portability or if you have a mains connection even during your holidays (in our mountain cottage, there is only 12 volt DC from the solar system suitable to power the CRF-1), you will be much better off with a upper class tabletop receiver, and it will hardly turn out more expensive, specially with the high prices paid for the CRF-1 in the German-speaking countries in view. The CRF-1 does not have luxury features such as station memories (which are sometimes very practical for checking for active Brazilians or Australians), but also passband tuning and notch filter, which can be used to master some critical reception situations with JRC or Drake receivers.

The rarity of the set in the German-speaking area is probably due to the fact that the receiver did not receive FTZ approval in Germany because it exceeded the magic 26.1 MHz frequency limit in the 1980s, but in Switzerland, too, the CRF-1 was only sold in small numbers due to its price.

A little later, semi-professional or amateur receivers from JRC, Yaesu and Kenwood were launched at similar prices, so many DXers (me included) saved up their money for a semiprofessional set… others probably preferred an impressive bulky portable (Grundig Satellit, Braun T1000) to the very technical-looking „silver-grey box“. German listener had always the Grundig sets in mind, when they were asked, what a real world band radio should look like.

Technical principle

Double conversion superhet with a high first IF.

Components

The set is equipped with semiconductors.

Technical documentation

Development

Further information

en/crf-1.txt · Zuletzt geändert: 2021/06/04 20:50 von mb