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I currently have a sae 5000 and 2 sae 5000a's. one 5000a works properly one 5000a works properly on one channel but the other channel passes no sound when in the processing mode and the 5000 passes sound in the processing mode but does not remove the clicks. Also on that there seems to be a faint high pitched tone in one channel. I have an oscilloscope and I went thru the working unit probing each I.C. and making note of what I get. For a signal I just put a mp3 of a sine wave with a simulated record skip on it so the working unit is trying to remove that skip, I can here the skip attempting to be removed with the invert button. I have probed the 5000 unit and I see discrepancies in my scope waveforms but my problem is I'm stuck at that point. The pc board isn't labeled the ic's as u1,u2,etc they just label 3 ic's with the sae part number and the other 5 with their sae part number, so my next step was going to be try to figure out what ic's are what by just following the board traces from each pin of an ic to it's component it's connected to and see if I can figure which ic is which. I'm not good at reading that schematic but I really haven't studied it . I imagine there are people that can just look at it and almost immediately see what's going on but that's not me. I work on the old rca selectavision players but I have service manuals for them and they go into great detail on how to find the problems, so I have pretty good luck working on them, but to go at a repair like these sae 5000 A little guidance may go a long way for me.
???? I was hoping someone may have some pointers for me. If it matters, the sae 5000 looked to be set up for 220 volt operation even though there was no sticker on the back indicating that but I changed it back to 110 volt and also added an on off switch. Any help would be greatly appreciated. Thanks in advance.

The majority of the ICs are RC4136 opamps with a few LM339 comparators sprinkled in. I have 5000A myself but never had to work on it, yet. Obtaining those ICs is no problem if one is found to be bad, what concerns me are the FETs, Q4,5 and 6. Q4 may not be too hard to find but not sure about Q5 and 6. I'll try to figure out they are.

for an update on this. I figured out which IC is which as far as u1,u2,etc and have further dialed in the problem (I think) with no incoming signal starting with u6 (the first IC to receive a signal if there was a signal there) I probe it's inputs and outputs and as expected there is no signal but when I get to the inputs and out put for #3 (this is pins 8,9, and 10) it kind of blows up my oscilloscope, then probing the inputs and outputs of #4 it's back to normal probing shows no signal. The #3 output is sent to u7 so that input and output also blows up the scope that's fed to uc8 so that blows up the scope. I don't know if this is the proper term but I would say an IC is oscillating but it seems like any of the IC's could be causing that and it's either feeding that oscillation back to the previous IC or feeding it forward to the next IC or if it was uc 7 it could be feeding the oscillation forward to IC 8 and backward to IC 6. The signal is only going thru a resistor or 2 and a cap or 2 , there's no diodes at that point to block a signal from going backwards, so I'm assuming the signal can just go where ever it wants to go. Keep in mind this is with no input to the inputs of the unit, I just turn on the unit ,probe away getting no signals but then hit one of the channels of the ic's and wham the screen on my scope blows up. So that's where I'm at with it at this point. If it makes any sense. I'm thinking that someone that has worked on these units probably knows exactly what's going on or has a pretty good idea. My thought was just to somehow disconnect pins 8,9 and 10 of u6 and then probe those pins and see if that ic is blowing up the scope, if it still does I know it's bad and I replace it, but if it shows nothing then I move onto u7 etc. The only thing with that is I'm not sure how to go about removing pins 8 9 and 10 from the circuit? Removing the entire chip was one thought or I also thought of snipping those pins and put a tiny wedge under the chip to make sure they are not making contact and then do my checking and if its not the culprit I could just solder the pins back together. I've already ordered replacement chips and sockets for them. When I change IC's I put sockets in figuring if I ever need to replace it again it makes the job so much simpler.
?? So That's where I'm at. As always any help is much appreciated. Thanks for your response.

another update on this. I tried snipping the negative and positive voltage input pins on u6 but could only snip the positive one but I was still getting some signal with no input so I removed u6 completely and now thru out the unit I have no signal anywhere with no input except the output pins 10 and 12 on u4 show a very small signal about 20mv at one pin and up to about 70mv on the other, but I only saw that spike that high once the majority of the time it was only up to about 30mv. I'm thinking that may just be noise it's picking up from all the flourescent and led lighting I have at the workbench, but I have made note of it. So my next step is put a socket in when they arrive and then install the new chip and see what happens.

Thanks Rick, only one of those SAE #s is on the handy dandy SAE cross reference chart. The "S" is missing on the schematic for the SD214. That was the only one I couldn't find, I'll look again now that I have the complete number.

the sd214 is the one I couldn't figure out on the schematic it's sae numbers I guess for those. I tried searching the actual numbers on the components and I also tried d214 with no luck so that one may be of help. I don't know if they are bad but I did run accross a forum entry where the poster stated he had a bad one, but the thread ends at that point. Thanks again.

for another update I replaced u8 thats the 4136 chip closest to the audio jacks that was giving the scope explosions and the unit now is working properly but now I need to work on the audio jacks. The old ones were broken so I put in some others but it tore the circuit board traces up somewhat getting the old jacks unsoldered so I need to figure something different, but at least the unit is working.

I replaced u6 not u8. u6 is closest to the jacks and it's the first chip to receive input.