RA17 page 18

These before and after photographs of the PSU/Audio comartment speak for themselves. This particular RA17 had not had the 10K resistor (right of centre) replaced with a higher wattage version as detailed in EMER E727 Mod Instruction 1. Like in my RA17, the bulk of the burning has come from the enamelled 47R resistor in the centre. In line with EMER E727 Mod Instruction 19, all three wire-wound resistors have now been replaced with metal-clad versions which are bolted to the side-wall of the compartment. Since a 165R resistor was not obtainable, the value was made up by two 82R resistors. Both tubular electrolytic capacitors have been replaced as have the two 220R resistors in the audio stages. Care should be taken when fitting C197 (100uF). Since this forms part of the -ve supply for the AGC, it’s +ve terminal is connected to the chassis. I have not found it necessary to replace the twin 32uF smoothing capacitor.

If you read the detailed description of the Crystal Calibrator in the Service Manual, it is clear that this is a very clever little unit. There were no real problems with this unit, but it was refurbished just the same. I have heard of one or two people who have had problems either with setting up the calibrator or with general operation. The following is what I do with a refurbished unit.

Switch the receiver mode switch to ‘Cal’ and tune the KHz dial to 500 or thereabouts, until you hear the beat-note. Adjust the core (L75) nearest the 2nd VFO for best quality tone then adjust the core furthest from the 2nd VFO for maximum loudness. Check that the beat note can be achieved at both ends of the KHz scale. If this cannot be achieved make a small adjustment to L75. The tone should spontaneously appear when the core is correctly set. This method works every time for me.