My money is on the little transformer having a zapped thermal fuse. Just check the secondary output and (with it unplugged from the mains) the primary resistance. I'll bet it it is open circuit.[/QUOTE
reading O/L between all pins
That sounds a bit high tbh. I'd have thought maybe a few hundred ohms DC resistance for a little transformer.
You should find (and be careful) that you have 240V between pins 2 and 4.
If that is present then you should have the AC voltage on the secondary between pins 6 and 8. Probably around 8 to 12 volts AC (haven't the circuit in front of me).
You should find (and be careful) that you have 240V between pins 2 and 4.
If that is present then you should have the AC voltage on the secondary between pins 6 and 8. Probably around 8 to 12 volts AC (haven't the circuit in front of me).
3.5V suggests the transformer may not be open (at least not totally so). Strange things happen though when things are 'open' with stray voltage coupling to various parts of the circuit... so I'm still thinking the tranny is still a fair bet.
Another possibility though is that something is pulling the voltage down (such as a shorted diode in the bridge)... I would have said that was unlikely but seeing as you can measure voltage we have to prove it.
So next test is to isolate one of the secondary pins (either of them) and then you measure the voltage directly between those pins. The transformer is unloaded and should show the full secondary voltage. If it does then we add a small load (resistor) between the secondary pins to draw a bit of current. Something like a 120 ohm 1 watt.
If it supports that OK then look for a problem in the bridge and following circuitry.
Another possibility though is that something is pulling the voltage down (such as a shorted diode in the bridge)... I would have said that was unlikely but seeing as you can measure voltage we have to prove it.
So next test is to isolate one of the secondary pins (either of them) and then you measure the voltage directly between those pins. The transformer is unloaded and should show the full secondary voltage. If it does then we add a small load (resistor) between the secondary pins to draw a bit of current. Something like a 120 ohm 1 watt.
If it supports that OK then look for a problem in the bridge and following circuitry.
With pin 6 de soldered i get as you said 9 volts , i had already removed and checked the 4 diodes , they were ok , just done the 2 , were these the ones you suggested checking ? ..
they were ok too . .
I only have 22 ohm resistors in 1 watt size , i will have a look around in my junk pile after work to see if i have anything more the size you suggested ..
i really appreciate your help with this ..
they were ok too . .
I only have 22 ohm resistors in 1 watt size , i will have a look around in my junk pile after work to see if i have anything more the size you suggested ..
i really appreciate your help with this ..
You're welcome 
So it sounds like one of two things is happening.
1/ The tranny has an issue and can not supply enough current.
2/ Something is drawing excess current and loading the tranny.
If this were the case then I would expect the tranny to get pretty hot pretty quickly. Beware if it does heat up then it may burn the thermal fuse out. If it sits there powered up and cold then it points to the tranny being defective.
I'll see what other quick tests I can come up with.
So it sounds like one of two things is happening.
1/ The tranny has an issue and can not supply enough current.
2/ Something is drawing excess current and loading the tranny.
If this were the case then I would expect the tranny to get pretty hot pretty quickly. Beware if it does heat up then it may burn the thermal fuse out. If it sits there powered up and cold then it points to the tranny being defective.
I'll see what other quick tests I can come up with.
Lets work on the basis that is OK. It equates to 85 milliamps loading which is probably more than a low power standby circuit would pull.
And this is where we could really use a circuit diagram...
Without and we have to busk it and try and get an idea what is happening. Look at your picture in post #31. I would now reconnect the transformer back in circuit and isolate (lift one end) of both of those two diodes to isolate that particular part of the circuit.
Having done that see whether the AC voltage on the transformer is still OK or is it very low again.
Depending on that outcome we can then look at reconnecting those diodes and then isolating the four diode bridge to see what happens there and whether that section is responsible.
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And another idea would be to isolate the transformer secondary completely and to place a current limited supply of say 12 volts across the points that go to pin 6 and pin 8. Pin 6 would be the positive. Even a good PP3 battery might prove something.
The transformer up to now is suggesting it is in fact OK... I'm surprised but the evidence points that way at the moment. The unknown is how much current the circuitry it supplies would draw and without a diagram its a bit of guesswork.
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