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Another Eico ST 70 thread

I realize, I have zero experience with breadboard and in that vein I seek some guidance here. What kind should I get? Where should I get it? Should I buy it to size or one larger piece and cut up? What do you cut it with? Now that I got that out. What kind of voltage rating should the Peco caps have?
 
The disks on the underside should be replaced for best sound,the pcboards are available at radioshack either perf board,or I saw some designed for 16 pin dips,that look like they would work,they could be left together,or broken apart.
Caps with a rating of 200v should be fine,possibly less,but I'm not sure.
You could check while the amp is on,and measure across the different parts of the PEC to check.
I verified my PEC pictured earlier,as wired correctly,with the center cap being 2200mmf instead of 330mmf
 
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Hey Scott, would you mind taking a shot of the back of that peco? (no rush) I was curious how they tied things together
 
Man, I owe you a beer for the service. I went back underneath, There were only 2 caps I didn't replace. Now I have. Maybe every resistor in the bottom except maybe 6 But they are in spec. Unto the Peco. I have to accumulate bits. Are there any connections at all on the beardboard? It appears that it is connected in lines vertically or am I seeing something wrong?
I'm going to get some breadboard and the values (components) we came up with yesterday and I'll see what happens. Thanks for getting me through this.
 
Here's a shot of the EFB prototype PCB for the Eico ST70/2080.
 

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Good morning,
I exchanged emails with Jon (Buzz) last night. Knowing he's spent more time than most in these and asked about the "warm sound" observation I made. He said he's found components on tone section drift ( which we came to before with our Peco sidetrack). He said something else which I was kind of overlooking. He said when tone controls are centered, response isn't flat. That being said how would you go about determining where the flat response setting would be?
 
An o-scope and signal generator, look at square wave response,Another way mentioned in the link for the ST84 was to adjust one channel where you like it,use the balance check feature to null it with the other channel,and reposition the knobs to flat
 
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When the time comes,put the sig gen @ 10Khz square wave into one of the aux inputs,and connect the scope to pin 2 or 7 of the 12AX7(V5 A or B)
and adjust the tone controls (loudness out,filters out)for the best square wave.That would be flat.
You could pull the 6SN7's ,or output tubes so as not have listen to the the signal,otherwise you would need to put load resisters on the amp.
I am not sure but I think the volume gets turned all the way up.

If the wave is distorted further investigation is warrented.
 
The only thing to watch out for,is accidently overloading the sound card inputs,and blowing the sound chip/card
I also have a DSO nano 203? 201? it can't measure to 20 khz,but the calibrator output is very good.
 
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