Hi chaps.
Ozan,
Having a quick look, R1724 is 324mV
Q1732 did fail before but was replaced. It currently tests ok using diode mode on the DMM and when replaced just now with a 2N5551 the Base reads 25.90v with the Emitter at 25.48v.
Q1734 is a new TIP31C following my carelessness and Q1736 also tests fine in diode mode.
Mark,
R1734 is difficult to reach but it reads 4¦¸ in circuit and measuring again, reads 0.062v, NOT 25.25v (not sure what happened there?)
CR and VR 1718 don't show any obvious failings, whilst C1737 isn't shorted and measures correctly at 3.6?F
On a different tangent, and I know this is slightly off the page of study and not sure if this will help, however, the 140v TP reads around 98v, yet when lifting the cathode of VR1718 the Test Point goes up to 160v. The +65v remains the same at about 25 volts. VR1712 is not faulty as it's cathode reads 179.9v. Anyway, just thought I would add that.
I did grab a selection of diodes yesterday whilst in town, just in case...
James55