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I'm having the same problem.,Try reflowing tr109 and110(i found them loose) and do a good visual inspection of the main board. I have ALL of my voltages +/ - 5v or so. You just might have bad solder connection
I actually ran out of solder so i'll have to try it later.....

[estate]

Sorry to say that today during measurements the transformer gave his last sigh, looks like that was the next thing to die on me.

I'll look to see if I can buy me a working one and use this only for the casing and front panel with buttons and pots.

Thanks for helping out.

[vtech]

Jan,
I see your readings may be on the high side but your measurements can not be all correct; as an example connectors W103,(part of W104),W105 and W115 are all tied to the same voltage lines yet you posted different readings!! Is it possible you are not making good connection or something wrong with the probe? -- 33.8V on W104 (1&2)?? while 16.7V on W103 and W115 and all three tied to the same line??

Either way, instead of going from point 123etc, pick out any one of the identical GND (same as metal chassis) as a reference point & leave it connected. Then measure each voltage in respect to it. Looks like the 24V may be a definite problem and if in fact you are reading something like 56V, there is a problem with TR103 regulation.
Tr103 is a simple series pass regulator, it is regulated by means of zener diode D106 which sets the output to be around 25Volts

[estate]

okay here are the readings from the power print, does not look good.

incoming power is 50 V AC on both 1-2 as 2-3 thats okay.
W101 reads +64,3 V on 1-2 and -67,8 V on 2-3
W102 reads +68,2 V on 1-2 and -64,5 V on 2-3
W103 reads +16,7 V on 1-2 and -16,6 V on 2-3
W104 reads +33,38 V on 1-3 and +16 V on 2-3 and -40 V on 3-4
W105 reads -16,6 V on 1-2 and +16,75 on 2-3
W106 reads 57,5 V on 1-2
W115 reads 16,5 V on 1-2 and -16,5 on 2-3

so far the measurement on the power print, I find the voltages very high, which explains why the R105 gets very hot (170 degrees Celcius)

I hope you can help me find the problem, if I read the measurements right there is one of the transistors who has a defect after all ?

[estate]

PS.

measurements of tr 101, 102, 103 are compared with newly bought parts (as they are not that expensive I bought me some when I was getting me a new pair of probes)

[estate]

got me a pair of new probes

Okay measured the transistors 101, 102, and 103 and they seem to be in range, all give about 4,5 K ohm on the MM (my son helped me to explain how to measure this )

I switched the power on and I notice that R105 ( 1K 1/2 W according to scheme) is getting rather hot, the measured temp is about 180 degrees celcius, so I am suspicious about the power it gets.

Although it only is for the power supply of the power led ? i can't imagine this is a good sign.

I am now going to remeasure the points mentioned before and give a listing of the voltages later.

[estate]

transistors, it is my bad.

I was measuring the voltages and my probe slipped, the transistor tr103 gave a bit of a high voltage when measured and after the slip it gave just about 9 volts, that's why I want to rebuild the power print, I have inadvertenly broken one of the transistors.

I am not going to put any probe in it again before i buy me a pair of new ones, totally isolated up to the tip.

Today the shop where I buy my parts is open untill 21:00 tonight and I hope they have the parts on stock. ( I mean it are parts that cost around 3 euro each, no blood flowing from that )

On W101, 102, 103 I measured voltages that seem to be okay until after my slip that's why I need new parts (i guess) and certainly new probes well isolated ones.

Around IC102 I did some measures and I started at D111 (AC to DC conv) the measured value was clearly within range so there is power on a part of the pcb, after that I messed up by shorting TR103 (just a short sparkle but a little too much I guess)

TP101, 102 was measured because I had an idea that when there was no power present there i should go way back to the beginning (that was my first measure to see if and how much power there was on the bias to exclude an eventually broken end stage)

[vtech]

Triacs? you meant to say transistors as there is no triac here. Why change them? Sounds like you may have jumped way ahead! Hope you have not inadvertently caused more damage
The proper way to troubleshoot is to first look at all supply voltages and see whats there and what is missing before trying to change parts. You mentioned probe slipping? did it short anything? What/where was the burned mark on the pcb? When powered up, Does it stay in protect mode? (what do you read around IC102?) How about at power supply connectors ? (W101.102.103 etc?)
Tp101, 102 has to do with bias adjustment and you will not read anything if the basic voltages are not present.

[estate]

BTW, sorry for beeing so blunt, I totally forgot to thank you for trying to help me out.

[estate]

Oh,

I also measured TP1 and TP2 (which should have at least about 20mV after 20 minutes of standby time) and it gave me a null reading 0 volt, when carefully truning VR 101 and VR101b there was no reading, so that's why I started to check the power print.