Salas hotrodded blue DCB1 build

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Let's say, hypothetically speaking, that I wanted to go for the gold and hit the 2A sweet spot. How big a PS would I need? I'm guessing new diodes of course. 12W resistor should still work, right?

I mean this is just hypothetical. I'd be crazy to even try it... :D

''Stage 3 = circa 2A. 40W dissipation per rail. F5 size sinks & Tx. 1R 12W''.:hot::hot::hot:
 
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All the mechanical work is done! :p

An externally hosted image should be here but it was not working when we last tested it.


Internal overview

  • 1st 65VA Transformer, double shielded with two power lines (Optical Volume Control & input switch) - upper left side
  • +/- Power Supply (27.000µF for OVC & 10.800µF for input switch)
  • 6 to 1 input switch
  • 1st +5V shunt reg for OVC
  • 2nd +5V shunt reg for input switch
  • Optical Volume Control pcb
  • Power Switch pcb (includes a solid state relays with no wear). The front switch must only handle +12V
  • DCB1 blue edition pcb
  • 2nd 65VA Transformer double shielded for the DCB1 blue edition


An externally hosted image should be here but it was not working when we last tested it.


The front panel


An externally hosted image should be here but it was not working when we last tested it.


The rear panel


An externally hosted image should be here but it was not working when we last tested it.


The PSU section


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The input and volume control & power switch section


An externally hosted image should be here but it was not working when we last tested it.

An externally hosted image should be here but it was not working when we last tested it.

An externally hosted image should be here but it was not working when we last tested it.


The DCB1 blue edition closer look


Now it´s time for wiring! :wave2:
 
No pot in this one yet. Just testing to make sure it is working.

Relay clicks, so I assume it is working. Unless I should be looking at voltage then only voltage I'm gettting is 0.63v(pin1) and 11.72v (pin10)

how to tell if audio fets are burned with dmm? is it similar to checking for B-E voltages. Or do I have to remove and test with my tester.

I will check solder joints and reflow.
 
Hi; I've got a couple of quick questions regarding the blue edition pcb board.

The .22u/100uf caps in the middle - what up with that? Is it two caps ( 1x .22uf and 1x 100uf) or something else?

I've noticed two resistors just before v+ / v- out (labelled '1') - are these on the BOM?

Thanks,
JG
 
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No pot in this one yet. Just testing to make sure it is working.

Relay clicks, so I assume it is working.

Play a CD and use your AC set DVM. Should be able to show something when there is signal. Even better if you got a low steady sine wave from a test CD or a computer file, easier to catch by most. Say 100Hz 0dB. Keep the black probe hooked to ground and poke around with the red. Is it going in to the board at all on the problematic channel? Does it pass the input 220R? does it exit the output 220R? If it makes it till there, does it pass the relay? It may click, but does it receive signal, and does it achieve contact? If its on the output, is it on the other end of the output cable? A joint, a burned part, a sticky contact, a problematic cable?


Alreadychecked voltages across 1-3 and getting around 9v. DCoffst is .003/.007. I will check for AC now

Thanks

Having DC offset, says its alive, your signal stops somewhere.