Jerry
I don't know where you are at on this, but.
The diode arrangement is called a voltage doubler.
First, there's a fuse resistor in there called Fuse RE5 connected right in
front of the 100uf cap. Did you check this? An ohmeter should read 22 ohms
across this (fuse) resistor. If ok, then, set your meter to the 250 volt DC
range (or whatever is closest going up). Put the meter plus lead on the
cathode of the right pointing diode (right side of the diode on the
schematic), and put your minus lead on the anode (bottom) of the vertically
pointing diode.
You should see over 200 volts. If so, leave your minus connection where it
is and move your plus lead over to the opposite side of the 500 ohm 10 watt
resistor in the cap section. A little less voltage but should still be
around 200. Then move...