[unl3a5h3d]

Okay this could be dumb but I have an old stereo system that the turntable motor stopped working, plus it is massive. The particular model is a Sears brand. There is no model number or name, all it says on the front is "Sears Solid State". Being that I have a separate turntable and I enjoy the sound of the headphone out on this thing I want to remove that "amp" and all of the needed extras and create a separate standalone amp. I know that I will need the power supply along with the amp board. But I'm not even sure my idea will work. Looking for some expertise. Well here are some pics. Thanks!
 
This is the front pannel of the whole system. 
 

 
Here is the overall inside. It's a mess.
 

 
Here is what I believe is the amp that controls the headphone output. The green, yellow, and black wires go to the 1/4" headphone output. The black on the other end goes on the board below, but the yellow and green go to a selector on the front where you can choose between headphones, speakers and all that. 
 

 
Another shot of the amp, I think. 
 

 
Here is the back pannel. Also the power transformer is in the immediate background. 
 

 
A shot of the power setup.
 

 

[unl3a5h3d]

Anyone? If this is going to be more trouble than it is worth I am not opposed to scrapping this idea. 

 

[wakibaki]

It can be done, obviously.
 
The amplifier works (I take it), it's a question of surgery. I know my way around amplifiers, I'd just take a pair of snips and go round cutting off everything unnecessary; the switched power to the turntable motor and the connections to the cartridge are mostly what springs to mind. Then you could connect up some power and check everything you want is still working.
 
Then remove any screws, bolts, nuts that are retaining the bits you want in place, move them without disturbing the connections, bolt them in a new enclosure, maybe add a new input connector using the wires that used to go to the cartridge and Bob's your uncle.
 
It may take a bit of thinking if you're uncertain which bits are which, but it should be fairly obvious from position and what's connected to what. You can always have a go, and if you break it partway through just deep six the lot. (boat anchor).
 
As to whether it's worth the effort, that's up to you to decide, but if you go ahead you'll almost certainly learn something in the process. The first thing will probably be how good you are at estimating the effort involved. 

 
w

 

[unl3a5h3d]

Thanks for the reply. I don't know my way around amps, yet lol. My main question is all of the extra stuff on the PCB of the "amp" that I will be cutting out, will they affect whether the amp works or not? For example the selector for the output on the front, once this is removed will it affect the playback because it is soldered onto the PCB? I will post pics of my progress. 

 

[wakibaki]

Quote:

For example the selector for the output on the front, once this is removed will it affect the playback because it is soldered onto the PCB? I will post pics of my progress. 

Ah, yeah, well, you will have to locate the terminals that carry the output on this selector (I'm guessing it's the source selector) if you remove it and make any new connections to the point where it was originally connected, but I guess you figured that out anyway. You can do this with a multimeter set on 'continuity'. That's the setting where the meter emits a 'buzz' or 'peep' when the probes are shorted together. Put one probe on the input selected and probe around until you get the sound (for each channel). If you haven't got a multimeter you can get a useful one for only a few dollars, they're handy for working on lots of things, cars, electronics, cars, the washing machine... You can just do this by visual inspection, but sometimes it's not easy to see and a meter gives a useful cross-check.
 
w

 

[unl3a5h3d]

I grew up doing residential electrical work so my knowledge base is on a larger scale lol. I will use my meter and decide what all I am going to take out. I got to work on it about an hour tonight, just trying to get everything sorted out, and decided I am going to try and make it more complicated lol. Most of the internals will just be moved into a smaller enclosure, removing only what is necessary to avoid messing it up beyond repair. I am also wanting to use the left and right power indicator on the right side of the front panel if possible, just because it looks awesome.