Marantz 18 scope not Working how to check if scope is faulty

The 2.5A 250v will be fine. Definately DO NOT use a 4amp. I would take it or send it to a professional before and further damage is done to it or yourself.

The 18 is the very first Marantz Receiver ever made and should be treated as such. One small slip with DVM lead or working it without knowing what you're doing could destroy it.

You would get a little further along here by following a dialogue. When someone asks a question, clear concise answers are needed and keep on topic.

Good luck and be careful around those high voltages measurements, it CAN kill you.
 
Stick with original fuse and I think your 575v cap is bad. The good part is that you still have voltage coming off the winding. C11 10uf @ 575v
 
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Umm, you'd need two 20uF in series to make 10uF. The nearest standard value is 22uF.

Good catch and great point, I totally missed that. I suspect it will work just fine because model 19 and 20 use two 10 uF 350v caps in series for this same purpose. Why? I have no idea.. I will say the 19 and 20 do not have HV transformer winding issues like the 18, maybe this is why? Could it be that the larger cap can withstand more voltage and current and therefore puts a larger strain on the windings till they fail? If you look at the current problem it looks as if the the HV is being loaded down by the cap. Total speculation on my part and off topic..

To the OP...
If you want to go with the larger value (22uF 350V) that matches the original values you could use 2 of this cap. If you contact Mouser you might be able cancel the other two before they ship. If it were me I would make it match the same value or just use the single large cap. If you decide to use the ones that you ordered it should work just fine and there is a precedent for it.

Sorry about the confusion.

From the model 20 schematic:
32214007577_de9c390403_b.jpg
 
Ok i will order the other ones . But they will no gonna be to short ? The orginal instsled its around 73 mm long , these are 31,5 mm long
 
You will be soldering two caps together positive to negative just like in the diagram so no the leads won’t be too short.
 
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