hI tony and the forum this is the info i have on the logik p/s type as above in my first post, the diode D14 type f 229B fairchild make? is a special type as i said no data on any datasheet sites . I have done out of circuit tests with a zener tester that gives me the actual voltage this diode reads 2.23v, a diode test on a digital meter gives me .701 then reverse probes then 1.862. in circuit working perfect, across the diode is 3V1, confused so am i, so what is it? a voltage reference diode? a zener so now tony you can see how i said it could not be a 6.8v did you possibly read it off ground always test a zener across for accuracy. Now for the last bit on the opto , when you buy a kit of parts you take everything of the pcb then fit the kit like i do , switch on and the set can be a write off WHY? because pin 1of the opto U4 on the board is on the opposite side to the line on the chip this then puts hi volts on to low volt lines blowing other pcbs beyond econonmical repairs SO BEWARE. and finally you can repair this board as standalone out of set on the bench various o/p are there at power on ie 5vsby 5vs to get all o/ps ground the anode of the diode next to relay ,i use the ground one nearby on the 24v skt there is no need to dummy load unless you are doing load testing ,this is the first of these logik p/s i have had , i have found a lot of the plasma and lcd smps can be tested and repaired as standalone on the bench , some times you have to alter logic from micro, and dummy load but so much easier on the bench. if anybody has a component level circuit please tell me what D14 is ? kind regards dave