Mezmerize DCB1 Building Thread

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Ignore that. The BC517 worked better than BC546 originally there, we had to occasionally add that cap there to avoid the startup relay from ocilllating.
So 4 100uf caps for Power supply , 1 for relay cap.
The board is labeled correctly for all needed parts.
 
Actually it's still not clear to me as well how to connect the input selector. I have 7 pins. What do I have to connect to the common pole of the selector ?

I fired today for the first time the board. Everything looks good. I have one rail a bit lower than the other. Additionally 0.1 mV DC offset on one channel and 1.8mV on the second channel. Is it normal ?

Thanks,

Davide
 
Actually it's still not clear to me as well how to connect the input selector. I have 7 pins. What do I have to connect to the common pole of the selector ?

I fired today for the first time the board. Everything looks good. I have one rail a bit lower than the other. Additionally 0.1 mV DC offset on one channel and 1.8mV on the second channel. Is it normal ?

Thanks,

Davide
 

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Horio,
Let me correct myself first, it's the first cap that gets replaced, not the second.
Technically I am not positive what the differences are. Both are bypass caps for the IRFP Voltage Reference. The film cap seems to offer better sound. I would buy both and try both.

Tea-Bag

I'm getting ready to solder in the caps, and wanted to make sure I put the 0.1uF cap in the right spot. I should be replacing the two 100uF caps closest to the Vref LED strings (5 LEDs) for hot-rod?
 
Dear All,

I have finished the circuit of my DCB1, just waiting to put it in a box, did not have any chance to use it.

Anyway, as I plan to use it as a pre for a F5, I was thinking of installing a relay on the power switch of the power amp, and derive 12 V from the relay of the delay start. If I got it right, like this I will power on the DCB1 and when the relay will open the power amp will switch on.

Does it make sense ? Is it as easy as I think ? The relay on the F5 will be 12 V as the one on the DCB1.



Thanks,

Davide
 
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Joined 2002
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I would prefer you will not drive a further (likely heavier) relay for an F5, because its power consumption and inductance can be overwhelming for the dedicated circuit, which is calculated to control 2 mini relays the most in the Mez's case.
 
Mes boards arrive

Many thanks to Tea-Bag, my Mesmerize boards arrived today in Australia!

I also, yesterday, just go home from hospital after surgery to reassemble my left wrist - snapped it into a thousand pieces falling over very clumsily... So I won't be building the boards for a few weeks yet.

I know this url http://www.diyaudio.com/forums/blogs/tea-bag/173-old-style-dcb1-information.html , but is there a complete circuit of the Mez somewhere with part designations which relate to the PCB?

I am using them on a balanced LDR volume control and I already have input selection so I am only building the buffers and shunt regulators - need to get that bit right.

Great xmas or whatever you do to all, and happy new year, thanks again Tea-Bag,