Psh.. I read on a site that was dedicated to crate amps somwhere that you could switch one dual OPamp for a Tl072- like the thread somwhere down there... so i figured i'd give it a go. I took the preamp board out and de-soldered the chip, put a socket in, and put a new chip in. all seemed okay. I figured (curious mind) that i'd see whats under the amp board.. so i took it out too have a look. it was packed with years of dust so i decided to disconnect the wires from it and take it to the garage to blow it out.. anyways.. i put it back in, hooked the wires up, turned the amp on, and POshboombang.. the thing was smoking and the fuse blew.. I took it to the shop because i dint feel like messing with it... so yea.. a few days ago i got a call saying i hooked up the two wires coming from the power supply wrong and i blew the protection diodes and some resistors. he said that could be the only problem or just the start. I dunno. but it was going to be like 100 bucks to have him fix it. Today i founfd a new to me/used to someone else head.. same sorta deal but a bit nicer.. so i dont really need my old one but i'd like to still try and fix it. Do you think hte diodes would have stopped the harm of anythng else or could much more have been blown? any thoughts would be good.. thanks.. (thinking of how dumb i am..)..
btw.. i might have a not-so-working crate 150 watt amp for sale soon if anyone wants parts
btw.. i might have a not-so-working crate 150 watt amp for sale soon if anyone wants parts
Be sure you didn't install the opamp backwards or put in the wrong opamp that was not pin for pin compatible. Assuming all that was done correctly, you probably did reverse the power leads. If you have a schematic and can find a way to scan and post it, someone here might could help. If it's solid-state the output transistors could be blown. The cost of the parts for repair are probably less than $10.00. If you have a volt-ohm meter or DVM that has a diode check function, you could do some troubleshooting. Posting a schematic and telling us which lead were reversed will help us figure out which parts most likely were damaged or blown.
Give us the name and model number of the amp and maybe we can find a schematic online.
Give us the name and model number of the amp and maybe we can find a schematic online.
thanks so much for offering all the help... I don have the amp here at the moment to get the model number, but i'm pretty sure its xx1500.. xx being two letters.. maybe GS..i think thats it. As for the opamp.. i looked up the number of the one i had and it said it was a dual opamp... same with the tl072 i put in. are there chances that they could be different even though theyre both dual opamps? the prob is.. i seem to have lost the other one.. so hopefuly i can find a schematic to get the right number again if the tl072 might not work.. Anyways, anyone know where i could find a schematic for this amp for free (well.. preferrably free..) Thanks again.
wow.. long time since i posted back on this thread.. i just found a schematic/board layout for the amp i got.. it's on its way at the moment.. hopefully i can scan that and post it. I have a neighbor (electrical engineer) that could prolly help me too.. if nothing else i'll rebuild the boards to make sure nothing is blown😉 Thanks.
I learned a lot of what I know from fixing other people's designs.
It's a lot of knowledge you can get with a small amount of
effort. 😎
It's a lot of knowledge you can get with a small amount of
effort. 😎
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