The TF2008 signal generator is probably not the best of units to use when working on the RA17 or RA117 as its output is a bit on the low side when aligning some of the modules within these sets. Where it does prove invaluable is in realigning the IF and Bandpass filters.
In a perfect world we would all have a Wobbulator like the CT501 or Polyskop but, of course, these units are becoming less common.However if you have a suitable scope the TF2008 can be used instead as it has the facility to sweep its output so the filters response can be seen on the tube of the scope. Additionally if the scope is a dual channel type calibration markers may be displayed on the second trace.
I have to say that this is not the ideal way to set up the 37.5 & 40 MHZ filters but it does work and is better than just "twiddling" to get maximum signal on the meter.Care has to be taken not to get HT on the generator output so the use of a suitable blocking capacitor is essential and a fused link in series with the output is desirable. Usually this link is supplied with the unit and one can just be seen laying infront of the unit picture below..
Brief Technical Description.
The Frequency output of the unit is 10 Khz to 510 Mhz in 11 bands with an RF output or 0.2 uv to 200mv E.M.F at 50 ohm. AM output is variable from 0 to 80% at 20hz to 15 khz. FM output 3 - 300 khz deviation . The sweep facility is controlled from the front panel and is variable up to the limit of the band that is in use i.e. 31.5 to 45 Mhz. 13 Calibration markers are provided on each band. Horizontal output is 8 V P-P Triangular Wave.
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