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5) One at a time, turn control knobs and compare outputs to figures below (resetting after finishing):
A) Treble to 10 –Fig.2; treble to 0- Fig. 3.
B) Hi-mid to 10- Fig.4; hi-mid to 0- Fig.5.
C) Lo-mid to 10- Fig.6; lo-mid to 0- Fig.7
D) Bass to 10- Fig.8; bass to 0- Fig.9.
BOOST AND SHAPE TEST
1) Engage channel select switch to back to lead channel.
2) Change scope-B to 5V/cm (still 1ms/cm).
3) With boost and shape on 0, compare to Fig.10.
4) Increase shape to 10- compare output to Fig. 11.
5) Increase boost to 10- compare output to Fig. 12.
CHORUS AND REVERB TEST
1) Return to clean channel (w/ channel select). Set output level to 0.
2) Set oscillator to –6dBV sine wave @ 100Hz.
3) Adjust R342 for no clipping @ U21/4.
4) Set oscillator to –26dBV square wave @100Hz.
5) Change scope trigger to A and scope-A to .5V/cm range.
6) Look at balanced out-R (J3) pin 3 (center).
7) Turn reverb knob to 10- see bumps in output as in Fig. 13.
8) Move frequency dial on oscillator back and forth around 100Hz- see signal bounce a little then settle.
9) Repeat 8) for each: Bal. Out-R (J3) pin 2 (left), Bal. Out-L (J4) pin 3 and pin 2.
10) Return reverb knob to 0.
11) Engage chorus switch with rate and depth of 0.
12) Look at Bal. Out-R pin 3, compare to Fig. 14.
13) It should have a small spike that moves back and forth approx. 1 div. at the rate of once every 2-3 sec.
14) Increase rate to max. Spike travel should speed up to about once every .7 seconds. Reset rate to 0.
15) Increase depth to max. Spike should travel about 5 full divisions. Reset depth to 0.
16) Look at Bal. Out-R pin 2 (left) and compare to Fig. 14.
17) Engage stereo/mono switch (S5). Spike gets bigger (Fig.15).
18) Look at Bal. Out-L pin 3 (center)- compare to Fig. 14.
19) Disengage stereo/mono switch- compare to Fig. 15.
20) Move probe to Bal. Out-L pin 2- compare to Fig. 15.
21) Set DVM to ohms scale.
22) Look at Bal. Out-R pin 1 (right) and see reading on DVM (number not important).
23) Engage gnd lift switch (S4) and see reading change to 1-open.
24) Repeat for Bal. Out-L.
FOOTSWITCH TEST
1) Set oscillator to –46dBV square wave @100Hz.
2) Set scope-B to 5V/cm, trigger on B.
3) Set output level to 12 o'clock.
4) Connect RFG4 to footswitch jack (J8) using 5-pin DIN cord.
5) Make sure both channel select and chorus switches are in, and boost and reverb pots at max.
6) Engage switches on RFG4 so that all LEDs are lit. Lead channel, chorus LEDs on front panel should be lit.
7) Output should look like Fig. 16.
8) Disengage reverb switch on RFG4- reverb bumps should disappear.
9) Disengage chorus switch. Chorus LED should go off and chorus spikes should go away.
10) Disengage boost switch. Compare to Fig. 11.
11) Disengage channel switch. Compare to Fig. 1. (Change scope range to 2V/cm, if necessary.) Clean channel LED should light.
12) Engage compressor switch on RFG4- see output increase.
13) Remove footswitch. Set front panel switches out and reverb to 0.
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