Hello to the Audiogon community. I'm a new member and have been getting my feet wet recapping my college days Marantz 2270 with the help of Catrafter's parts list. Everything is going great with thet project.Thanks Tom and to everyone who contributes to this community. It's an amazing resource.
Now on to the issue at hand. I recently was fortunate to stumble across a reasonably priced Luxman M4000, C1010 and T110 set. Wow what beautiful equipment! I opened up the amp to Deoxit the attenuators pots, they were a little scratchy. While I was in there I thought I would check the offset and idle current. Offset was perfect, but I'm not sure about the idle. It's supposed to be 100ma. When I connected the meter, after warming it up a bit it started at around 100 but just kept rising consistently, like 1ma every couple of seconds and settled after about 10 minutes to 132. Adjusted it down and went to the other channel. Same thing. When I went back to the first channel it started out at about 80 and worked its way up to about 110 and I adjusted it again.
I guess the question is whether that is a normal way for the idle current to behave? It's the type of amp that you remove a fuse to set the idle, so maybe it's just warming up the circuit every time and it' normal, but I'm not sure. Of course I don't think it sounds quite as rich as it did before I messed with it, but that could just be perception. I'm feeling like maybe I should have left it alone because it sounded great and the offset was spot on, so maybe the idle was also.
Now to show the experienced how much I appreciate their help I'll give you something to chuckle about. Yes, I did the obligatory fireworks show, damn near arc welded the leads to the nearby (too nearby!) sheet metal plate. Used micro hooks after that (and after replacing a main fuse) Hopefully that's not part of the problem, if there is one. Thanks again for any guidance.
Now on to the issue at hand. I recently was fortunate to stumble across a reasonably priced Luxman M4000, C1010 and T110 set. Wow what beautiful equipment! I opened up the amp to Deoxit the attenuators pots, they were a little scratchy. While I was in there I thought I would check the offset and idle current. Offset was perfect, but I'm not sure about the idle. It's supposed to be 100ma. When I connected the meter, after warming it up a bit it started at around 100 but just kept rising consistently, like 1ma every couple of seconds and settled after about 10 minutes to 132. Adjusted it down and went to the other channel. Same thing. When I went back to the first channel it started out at about 80 and worked its way up to about 110 and I adjusted it again.
I guess the question is whether that is a normal way for the idle current to behave? It's the type of amp that you remove a fuse to set the idle, so maybe it's just warming up the circuit every time and it' normal, but I'm not sure. Of course I don't think it sounds quite as rich as it did before I messed with it, but that could just be perception. I'm feeling like maybe I should have left it alone because it sounded great and the offset was spot on, so maybe the idle was also.
Now to show the experienced how much I appreciate their help I'll give you something to chuckle about. Yes, I did the obligatory fireworks show, damn near arc welded the leads to the nearby (too nearby!) sheet metal plate. Used micro hooks after that (and after replacing a main fuse) Hopefully that's not part of the problem, if there is one. Thanks again for any guidance.
