Recently Restored SA-9900 working great now blowing fuses

I recently did a restoration on a low miler SA-9900. Full recap,including ps caps. Removed all the known failure prone transistors. I ran and tested the unit for many hours. Sold it to a fellow across the country and he reported back how happy he is. The next day he reports that after he hooked up a Project tt pre amp through the AUX terminals and did some tone adjustments. It blew a fuse.
Apparently it keeps blowing fuses now.Any thoughts?I have never used a tt pre amp through AUX before.
I try to find the 8a 125v fuse, but it was too small compare to the original one. Can I use 8a 250v for it? or which size of fuse can I replace?
 
You likely have shorted outputs. Do not power it up until a competent tech has checked it out!Something is amiss.
 
It's not the voltage that's blowing it, it's the current draw (amps). And no, you cannot use a larger amperage fuse because if you have a short, a higher (amp) rated fuse will allow more current to flow where it's not supposed to, and you'll end up burning up more of the circuitry. I don't know your level of expertise, but if you're sure you want to continue the repair, you'll need a DBT (Dim Bulb Tester) and how it's used, a multimeter, and knowledge of how to test individual components (like resistors, transistors, diodes, caps) with the multimeter. The most effective and least costly component you'll need to perform this repair, is time.
So what I have to do now? should i take it to the repair shop? because I did bought the 8a 125v fuse, but it is smaller than the original one. and it was not fit.
 
You own a very nice piece. Well worth investing to have it properly restored. Just repairing it will not keep it running for the long term. There are heat issues on the power supply board and a lot of transistors that should be replaced including I suspect the outputs. That said said all the parts are available and after 40 years it will benefit greatly from a recap/restoration.
You need to try and find the right person to do the restoration if you are not up to it. The 9900 is not the easiest piece to work on. I am sure this forum can lead to the right person. gl
 
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