Hi all, I am new here but I have been lurking trying to get a general handle on how this amp works; I am trying to repair my father's series 2 phase linear 200 preamp & 400 amp. It has been in a shed for approximately 30 years. He thinks he may have had it on too loud and it just "stopped working". I found a resistor taped to the case of the amp, he says he recalls looking inside the case and seeing a similar cracked resistor but he never got around to fixing it. Well, here I am, trying to repair it. I took some photos: the only thing I noticed inside was a few cracked resistors on the right side of the unit. I looked for burned or other cracked things but did not see anything. You will have to forgive me, I am still learning some terms, but the round yellow chalky things on the PCB control board also appear to possibly have been cracked (see photos).
I did not attempt to power on the unit yet. I want to get it in running order again, I do not want to "upgrade it" yet since I want to hear what it sounded like to my Dad first, and want to do this in the easiest most cost effective way possible. I see references to a White Oaks replacement PCB control board, but I am hoping I don't need something that expensive.
Also, I keep seeing the term "bad outputs" and "replace the outputs" but I cannot seem to infer what exactly an output is/does and what it looks like. I didn't want to power on because I am scared of a capacitor or something killing me. I do not have experience with stereos, but I do have extensive experience assembling computers, and I have made my own custom motorcycle wiring harnesses, but this is new territory for me. I replaced tubes in my other Luxman and Audive equipment as well, and also repaired my old turntables so I do like to tinker if I know what I am tackling.
Also, I downloaded the service manuals and user manuals. I do not have a variac, dim bulb tester, or oscilloscope or anything of that nature. I do have a basic multimeter. I have soldered things though, but need a new soldering iron if I will need to solder. I do not know if the preamp works, it appears very clean, but a squirrel chewed off the end of the power cord and I will need to create a new power cord terminal as such as part of this as well to test it. The tone toggle switch is stuck in the in/flat position on the preamp.
Do you think I should just buy some of those resistors that appear cracked and solder new ones on? Where do I buy them? Are the cracked yellow things bad too? Is there anything else I really need to do whilst in there? How much is all of this going to cost me roughly? Sorry these questions probably sound very amateur but the advice seems to generally indicate that you need specific parts from specific suppliers or it won't work right and I don't want to screw this up!
I did not attempt to power on the unit yet. I want to get it in running order again, I do not want to "upgrade it" yet since I want to hear what it sounded like to my Dad first, and want to do this in the easiest most cost effective way possible. I see references to a White Oaks replacement PCB control board, but I am hoping I don't need something that expensive.
Also, I keep seeing the term "bad outputs" and "replace the outputs" but I cannot seem to infer what exactly an output is/does and what it looks like. I didn't want to power on because I am scared of a capacitor or something killing me. I do not have experience with stereos, but I do have extensive experience assembling computers, and I have made my own custom motorcycle wiring harnesses, but this is new territory for me. I replaced tubes in my other Luxman and Audive equipment as well, and also repaired my old turntables so I do like to tinker if I know what I am tackling.
Also, I downloaded the service manuals and user manuals. I do not have a variac, dim bulb tester, or oscilloscope or anything of that nature. I do have a basic multimeter. I have soldered things though, but need a new soldering iron if I will need to solder. I do not know if the preamp works, it appears very clean, but a squirrel chewed off the end of the power cord and I will need to create a new power cord terminal as such as part of this as well to test it. The tone toggle switch is stuck in the in/flat position on the preamp.
Do you think I should just buy some of those resistors that appear cracked and solder new ones on? Where do I buy them? Are the cracked yellow things bad too? Is there anything else I really need to do whilst in there? How much is all of this going to cost me roughly? Sorry these questions probably sound very amateur but the advice seems to generally indicate that you need specific parts from specific suppliers or it won't work right and I don't want to screw this up!
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