For the most part, whether it is an RA17, and RA17L (or other) or an RA117, the basic operation is the same, so for this article I will simply refer to the receiver as an RA17.
Unlike modern HF communications receivers which will essentially work ‘straight out of the box’, nothing is automatic in the RA17. It needs to be configured by the user, and for that, some understanding as to how the the receiver works is required. Most of this is actually covered in the manual, but not everyone has a manual.
The RA17 does not have ‘band switching’. Instead, the user selects the MHz by way of the MEGACYCLES knob. It should be noted that calibration of the MHz scale is nominal. Thus the user needs to fine tune this setting for maximum noise from the loudspeaker. To an experienced user, this is second nature. However, the first-time user may experience difficulty with this because of various factors. So here is a quick-start guide to setting up your RA17.
It is imperative that you have an aerial connected. Sounds silly, but a good aerial is really necessary for reasons which I will come to.
Set the controls as follows:
RF/IF GAIN … fully c/w
SPEAKER … ON
BANDWIDTH … widest setting (fully c/w)
LIMITER … OFF (up)
System Switch set to MAN
ATTENUATOR … MIN
AF GAIN … 50%
The Preselector has two controls. Initially set the switch to WIDE BAND.
If you now rotate the MEGACYCLES scale from 0 to 29 or vice-versa, you should hear an increase in noise for each of the markings on the scale. This is the characteristic “chuffing” that users often talk about. The noise that you are hearing is wide-band noise at the antenna. Without an antenna you will hear nothing. However, the RA17 was not designed to be operated in this manner. In wide-band mode there is no input selectivity and sensitivity is very poor. You may rightly ask why is there a wide-band setting in the first place? I’m not really sure. There are specialist external pre-selectors, like the MA197, but my feeling is that the wide-band setting is there as an aid to setting up only.