Peavey Amplifier repair. Model: PV-4C
An owner of a restaurant and a friend of mine brought me a very old amplifier. The main problem with this amplifier is when you power it up, it comes on for a few seconds then it shuts down. I could hear the fan come on but that is about it.
I have seen this kind of problem before and I think I can fix this one. The only problem I am facing with the kind of repair is finding parts for this amplifier. It is old and in my country, it is very hard to find such parts for old equipment.
It was very dirty on the inside and all the parts were covered with dirt. I used a powerful air blower to clean the inside of the amplifier. Now I could see the part numbers on the components inside this equipment.
Usually with this kind of amplifier, when powering the machine and it goes to shut down, it is a problem with the main output power transistors.
In this case, I found three transistors shorted out. The part number is 70483180 NPN transistors. I called almost every story in Bethlehem area to look for these parts but I could not find any. Since I could not locate them in stores, I started calling my repair friends in the city and to my surprise, I found the same brand amplifier, but the guy told me that is was dead, it shuts down after few seconds which is the same exact problem that I facing here. I went to his store and got it for free. I was thinking maybe I could get find three working transistors out of that amplifier.
I opened that machine and I was so lucky to find five working transistors. I replaced three working transistors into my clean nice old amplifier and when powering the machine up, it worked very nicely.
I was actually shocked at the quality of the sound that this machine was producing. I called the customer and he was happy and shocked at the same time that this old machine is alive again. We went back to the restaurant and I installed the amplifier for him. It sounded really great and at the end of job well done, he offered me a nice meal and of course paid for the repair job after I gave him a very good discount.
This article was prepared for you by Waleed Rishmawi, one of our ‘Master Authors’ and currently working in the Bethlehem area of Palestine repairing electrical and electronic equipment. Please give a support by clicking on the social buttons below. Your feedback on the post is welcome. Please leave it in the comments.
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