Sony Corporation, Tokyo
CRF - 1
überarbeitet am 23.10.2010
The Sony CRF-1 appeared on the market in 1981 as a successor of Sony's bulky and heavy high end portables CRF-320 /
CRF-330K, Sony had invested much effort and time in the development, but technical progress made this receiver soon a bit outdated, so the elevated price was not warranted in the eyes of many consumers.
The Sony CRF-1 is portable high end receiver with the cabinet size and appearence of a desktop amateur radio transceiver, but the carrying handle and the long telescopic antenna make it a real portable. The handle can be used as tilted stand.
A coarse dial giving You an idea about the region of the shortwave spectrum You are tuned to is expanded over the upper part of the front panel; a similar approach is taken with the Philips D-2999. At the right, You find the analog signal strength meter calibrated in S units.
At the left hand, You find the main switch and next to it the controls for volume A.F. gain and R.F. gain. At it's right, in the middle of the front panel, You find the red LED frequency display giving You the exact reception frequency with a resolution of 100 Hz, the dark red LEDs might be difficult to read, when You operate the receiver in direct sublight.
At the right of the main tuning knob just below the signal strength meter, You find the also very important preselector control. In the band segments 150 kHz - 400 kHz / 400 kHz - 4 MHz / 4 - 30 MHz You have to tweak for signal maximum. The tiny preselector dial gives You only an impression at which part You have to look for the signal maximum. Compared to this really tiny dial, the preselector dials as found in the ICF-6700 W / 6800 W or the Yaesu FRG-7 / FRG-7000 are much easier to use. With a switch below the preselector control, it can be deactivated in uncomplicated reception conditions to speed up tuning the receiver. Juste next to the preselector switch, You find the noise limiter switch.
Below the frequency display, You find tiny pushbuttons to activate dial illumination, battery strength indication on the meter and to activate the power consuming digital frequency display; at the right the slightly bigger pushbuttons for the modes AM - wide (10 kHz) / AM - narrow (4,4 kHz) / USB / LSB / CW (3 kHz).
At the rear face of the receiver, the jacks for a tape recorder output, timer operation and muting and the connectors for antenna and earth and a BNC antenna jack are located. A rotable switch at the top face of the receiver is used to select the external antenna and the telescopic antenna. For both antennas, a - 20 dB attenuator i provided.
The signal from the antenna connector first has to pass one of eight electronically switched octave bandpass filters followed by the preselector. In the first mixer, the high first intermediate frequency of 55,845 MHz is generated. A VFO is used to tune the receiver between two 100 kHz points, with the VFO signal, the secind I.F. of 455 kz is generated in the second mixer. After having passed the ceramic I.F. bandwidth filters and I.F. amplifier stages, the signal is fed to a diode demodulator for AM and a product detector for SSB reception.
In practical use, the receiver had an excellent performance when it was designed and gives still reasonably good results as compared witth other portable receivers today. But most listeners, who need not absolutely to be independant from mains power lines (in our cottage in the Alps, we only have 12 Volts DC power from solar panels), might find a cheaper solution to achieve the same results: nearly all compact desktop receivers are sold cheaper in the German speaking countries then this 30 year old "goodie", they offer several frequency memories, high quality I.F. filters, passband tuning and in some cases a notch filter.
© Martin Bösch, 17.8.2005