Gregory
Soundco Kid
Let's get started on the C33 which is 28 years old now.
Finally underway
The C33 is update is finally getting started after YEARS of procrastination. When did Ron-C do the C34V? Dec 2007? That's how long ago. The plan is to service the HIGH LEVEL INPUT boards first, then the Power Supply. Let's have a look at some Power Supply photos.
Main power supply caps
The NEW Nich 4,700uf VZ's @35V are similar but physically smaller that the originals.
Power Supply rectifiers
Rectifiers in the rear-most compartment
There appears to be (at least) eight 1N5395 diodes in the C33. I may replace them with Fairchild 1N5408.
There was some trouble finding suitable diodes. The Parts List says they are 400V, 1.5A type and I haven't found a GOOD replacement, except for the Fairchild 1N5408 which are 1000V, 3A. The lead diameter of the existing diodes is 0.032".
Top cover PCB
The first board was removed and JUICED UP with Deoxit. I see the TWO caps at the end are in the signal path.
Two caps at the end look like general purpose electrolytics. These will be replaced with FG (Fine Gold.)
They are 10uF, 50V when the schematic calls for 16V. Will need to order FG for these.
10uF caps on top PCB. There was a small rust spot in the center of the Monitor Amp INPUT switch which came off pretty well but left tool marks.
End of Day 1
Suppose someone could go through this preamp in 4 - 6 hours but how many things would get broken? What corners would be cut? It's going to take easily 4 - 6 weeks to do this job.. and possibly longer.
But it will be fun.
-Greg
Finally underway
The C33 is update is finally getting started after YEARS of procrastination. When did Ron-C do the C34V? Dec 2007? That's how long ago. The plan is to service the HIGH LEVEL INPUT boards first, then the Power Supply. Let's have a look at some Power Supply photos.
Main power supply caps
The NEW Nich 4,700uf VZ's @35V are similar but physically smaller that the originals.
Power Supply rectifiers
Rectifiers in the rear-most compartment
There appears to be (at least) eight 1N5395 diodes in the C33. I may replace them with Fairchild 1N5408.
There was some trouble finding suitable diodes. The Parts List says they are 400V, 1.5A type and I haven't found a GOOD replacement, except for the Fairchild 1N5408 which are 1000V, 3A. The lead diameter of the existing diodes is 0.032".
Top cover PCB
The first board was removed and JUICED UP with Deoxit. I see the TWO caps at the end are in the signal path.
Two caps at the end look like general purpose electrolytics. These will be replaced with FG (Fine Gold.)
They are 10uF, 50V when the schematic calls for 16V. Will need to order FG for these.
10uF caps on top PCB. There was a small rust spot in the center of the Monitor Amp INPUT switch which came off pretty well but left tool marks.
End of Day 1
Suppose someone could go through this preamp in 4 - 6 hours but how many things would get broken? What corners would be cut? It's going to take easily 4 - 6 weeks to do this job.. and possibly longer.
But it will be fun.
-Greg
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