Vintage Synth Repair

Hi folks,

I'm replacing the 110v PSU in one of these - have located an equivalent (not
Yamaha)  230v SMPS with +5V and +/-15V.

I have the commonly-available Service Manual off the net, but this does not
include schematics or a description pin-out of the PSU connector.  Also the
overlay seems to show one fewer pin on the DC-output connector than the than
the Real Thing actually has.

Now, it was easy-peasy to figure out the 5V (pin1+2)  and +15 (pin8) and
-15V (pin 7), and two commoned earth pins (3+4), but there are two more pins
pins (5 and 6) with separate tracks leading away. I can no longer check what
is on them voltage-wise or whatt their purpose is.

Any ideas, or anybody have the schematics ?

cheers

geoff