CR-6B
This receiver was built by AWA in the late Fifties. It is a General Coverage HF receiver. It also covers the LF bands for monitoring of NDBs.
COMMENTARY
The CR-6B is typical of many commercial general coverage receivers of its era. It was used by various organizations in a commercial role. My example is ex Department of Civil Aviation (DCA). The receiver is a dual conversion superheterodyne type. Band switching is performed by coil switching.
The receiver is fully valve except for the power supply and detector stages which utilize solid state diodes. The receiver is available in a case or may be mounted in a 19 inch rack.
The CR-6B has all the bells and whistles for a receiver of its day, without going mad on the amount of money spent. There are four available bandwidths, from 700Hz up to 6kHz. There is a BFO control, an antenna trimmer and a noise blanker. AGC time constant can be set to Fast, Slow or Off. When the BFO is on a product detector is used rather than the diode detector. These features make the receiver a pleasure to use. The tuning mechanism is well weighted. 500kHz calibration points are used to correct the dial readout. A meter gives a received signal strength indication. There is an optional crystal board which will accept up to six crystals. A capacitor allows fine tuning of the crystal channel. Other controls are AF gain, RF Gain, StandBy, On, Cal, BFO switch and of course the Band Change switch.
600 ohm audio, speaker outputs and break-in facilities are available via the rear panel. There is no built in speaker but there is a phones jack.
The CR-6B is a classic fifties receiver. It is excellent for use as a general purpose ham receiver where you need to be able to scan through the bands. It has all the features that make this receiver a pleasure to use.
TECHNICAL SPECIFICATIONS
Frequency Range: 200-540kHz, 2-25MHz
Modes: AM, MCW, CW, SSB
Sensitivity: 3uV
Power Requirements: 240VAC
Selectivity: 700Hz, 1500Hz, 3000Hz, 6000Hz
BFO +-3kHz
CONSTRUCTION
The receiver is neatly laid out, typical of many receivers of the time. There are plenty of firebottles to look at on the chassis. Most components are readily accessible although access to some areas requires removal of the front panel. Note the "DCA Accepted" stamp on the unit below. The CR-6B was widely used by the DCA. now known as Air Services Australia..
OVERALL RATINGS
Engineering rating (taking into time of design).
A typical comms receiver. 8.5/10
Fitness for purpose rating
A flexible and reliable design. 10/10
Usefulness as ham equipment rating
A nice comms receiver with some useful features. 9/10