The Sony CRF-220 comes in the shape of a large and heavy portable multiband radio, it probably is one of the largest and heaviest shortwave radios ever built by Sony - aside from the CRF-320. The leatherette covered radio comes with a rugged carrying handle and two antennas at it's top face, the detachable front cover is equipped with a time zone calculator disc and a compartment for the logbook and the user's manual.
The receiver has the dimensions of 45,2 x 32,5 x 19 cm and a weight of 13,8 kg, is is even larger and heavier the the Grundig Satellit 3400. With six UM-1 batteries inserted, the radio is not the one, You would want to take with You on a hike through the mountains. The set can also be powered from 110, 127 or 220, 240 V mains, make sure that the power selector switch at the rear is in correct position before You power up the receiver.

The top third of the frontpanel is taken by the speaker grill with the oval speaker of 8 x 12 cm diameter, all controls are arranged in the rows below the frequency dial windows, in a bottom row, You find all necessary connectors and some switches for less important functions.
In the middle of the front panel, You find from the left the signal strength meter that can also be switched to indicate battery strength, at the right the frequency dial windows. The switches for dial illumination and for signal / battery strength indication of the meter are located just below it.

At the right of the signal strength meter, the selected shortwave band is displayed in a small window, the 500 kHz segments are selected with the rugged rotary bandswitch at the right small face of the receiver. To determine the reception frequency, the number displayed on the right vertical 0 - 500 kHz dial is added to the frequency displayed in the selected band window. For example: the receiver is switched to band SW6 with a start frequency of 5,800 MHz and is tuned to 300, so the active frequency is 5,800 + 450 corresponding to 6,250 MHz. When You are tuned to a station on a known frequency, You can use the "calibrator" knob to move the dial pointer line to signal maximum.

The shortwave bands SW2-19 are selected with the pushbutton below the corresponding frequency dial, the resolution of the frequency dial is around 10 kHz, what will be enough to identify a station in most cases.
In the middle window, You find the vertical dials for SW1, medium- and longwaves, use the resepective pushbutton to select the waveband an the tuning knob below to tune in to the desired frequency, the frequency marks are quite coarse and there is no fine tuning knob provided.
At the right, You find the frequency dial, the two waveband pushbuttons and the tuning knobs for the VHF / FM broadcast band. In contrast to the CRF-220, the CRF-230 tunes two VHF bands: the standard FM broadcast band 87,5 - 108 MHz and a second VHF band 64 - 88 MHz to cover police and fire brigade traffic. Because of this extended frequency coverage on VHF, the set was not available in Germany.

In the bottom row of controls, You find the tone controls for bass and treble and the volume control as well as the mains switch below the signal strength meter. Below the volume control, the RF gain control is located, manual gain control is active, when the button is pulled out.
In the small bottom row of connectors and controls, You find the headphones and earphones sockets, next to it below the shortwaves tuning knob the BFO note control, the BFO is activated for CW and single sideband reception by a tiny switch it it's right.
Some switches below the middle tuning knob activate special functions on the AM bands: an attenuator in the LOCAL position, a noise limiter in the ANL position and the WIDE and SHARP bandwidth filter's, with the narrow filter active, You can suppress signals from an adjacent channel station.
Below the right FM tuning knob, You find the switches for the squelch function and the AFC active in the FM broadcast band.

On the rear, You find an antenna selector switch and screw terminals for LW-SW1, SW2-19 and VHF antennas.
The jacks for an external speaker, tape recorder, a DIN tape recorder connector, the mains calble connector and a DC input connector to power the radio from a car battery by help of Sony's DCC-126 car battery cable are also located on the rear face of the radio in the right lower corner. The jack MPX OUT is used to feed an external stereo adaptor, the signal could be fed back to the CRF-230 by means of the AUX IN jack.

The CRF-230's operation scheme in the LW, MW, SW1 and FM bands is mostly self explanatory. Connect to mains (make sure to have selected the correct voltage), set the power switch to "ON", adjust the volume, press the respective white bandswitch pushbutton and tune the set until You can hear something. The set has two telescopic antennas located on the top face: the left one is the AM antenna for shortwaves, at the right, there are two antennas to be pulled out for FM reception. To unlock the antennas, press them in to unlock an then pull the antennas out.
For shortwave reception, You have to select the desired waveband with the band selector rotary switch at the right small face of the radio with the button SW2-19 depressed. Make sure, the radio will cover the desired frequency for stations slighty out of the borders of the official shortwave bands, the former BBC channel on 9410 and ERT Athens cannot be received, as the 31 m - band is covered from 9,500 - 10,100 MHz only. Normally, You have to make the calculation from the starting frequency and the kHZ to add on the SW2-19 dial to reach the desired frequency. E.g. to listen to Deutsche Welle from Cologne on 6,075 MHz, set the receiver to the 49 m - band starting at 5,800 MHz, set the dial to 275 (5'800 + 275 = 6'075), and You should arrive to receive the signal on the 6,075 standard frequency from Germany. This sounds a bit more complicated then it is in reality.
When a long wire antena is in use, use the attenuator in position LOCAL or better the manual gain control MGC to reduce the level in very high antenna level situations that might cause overloading the receiver, in case of adjacent channel interference try the SHARP i.f. bandwidth.

Technically, the SONY CRF-230 acts as single conversion receiver with an intermediate frequency of 455 kHz on long-, mediumwaves and SW1 and as double conversion receiver with a first i.f. of 1,6 - 2,2 and a second i.f. of 455 kHz in the ranges SW2-19, the U.K. version uses an intermediate frequency of 468 kHz. The band selector connects the linear 500 kHz VFO for the different shortwave bands. In the FM broadcast band, the CRF-230 acts as standard single conversion receiver with an i.f. of ZF 10,7 MHz.

The bottom line: the Sony CRF-230 is a collectors set only rarely found on the used market as it's catalogue price was exceptionally high and there has been restricted availability in Western Europe due to the set's coverage of additional portions of the VHF band.
This technically quite sophisticated set will be surpassed by modern shortwave reeivers as far as shortwave performance is concerned by far, it it a good set for program listening, but it does not cover out of band listening and the tuning scheme is a bit old fashionned; so quick frequency checks are not made that quickly - but the CRF-230 is a great radio not only to be stored somewhere in a damp cellar or workshop. Nowadays, it is still not allowed to monitor frequencies out of the standard FM broadcast bands in most countries, but posseding the radio and operating it on frequencies allocated for public broadcasting is no problem anymore.