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Old 23rd August 2012, 09:53 AM   #2571
AndrewT is offline AndrewT  Scotland
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Pass specifies 18V for the B1.
You can try using 24V, but do expect there to be some, maybe small, difference in performance from a real B1.
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Old 23rd August 2012, 09:55 AM   #2572
Salas is offline Salas  Greece
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You used those capacitors for what? Power rail's decoupling? Don't use series resistors with batteries, 9V or 12V are acceptable.
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Old 23rd August 2012, 10:05 AM   #2573
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I connected 100uf 10v rubycon za caps to legs of fets to make them reach better high frequency response.I think about bigger capacitors for power supply.But your circuit is +-10 volts and there is no +-10 volt lead acid battery.So how can make +-10 volts in a simple way?When connecting 200ohms 3w serial resistors to 12v accumulator , 10ma current of B1 preamp makes there will be a 2volts drop right?Is it not a true way?
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Old 23rd August 2012, 10:34 AM   #2574
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Or maybe a serial 2.2v 3w zener diode?
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Old 23rd August 2012, 10:39 AM   #2575
AndrewT is offline AndrewT  Scotland
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3W, why?
500mW 2.2V will pass 181mA all day. Yes it will be hot.
Two channels of B1 use ~20mA. That gives a dissipation across the Zener of just 44mW, not quite 10% but enough for good regulation of the dropping voltage.
Might be better to use a 400mW Zener. Or maybe a string of 3 diodes.

But listen to 24V first.
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Old 23rd August 2012, 11:17 AM   #2576
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I am using Salas DCB1 not nelsons circuit.12v batteries may be 12,8 volt at full charge so it makes 25,6volts so it is going to be too much.I will try serial diodes with accu,make about 2 volts drop on diodes and after that connect 10000uf 16v caps.So i think i will get +- 10,5 volts.I will buy 12v accumulators tomorrow i think.
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Old 23rd August 2012, 12:34 PM   #2577
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I now connected 9v sony nicad batteries for temporary listening.My denon amplifier was not clear enough but now it sounds clear like F5 amplifier.What a change!Guitars are better bass is better everything sound is more clear!
May be extremely clear sound with F5 amplifier.
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Old 23rd August 2012, 03:35 PM   #2578
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Quote:
Originally Posted by AndrewT View Post
Pass specifies 18V for the B1.
You can try using 24V, but do expect there to be some, maybe small, difference in performance from a real B1.
i have 30V on my DC coupled B1 just because i have +15 and -15Vreg on hand .. sounds quite good and don"t fry yet
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Old 23rd August 2012, 03:40 PM   #2579
AndrewT is offline AndrewT  Scotland
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the DCB1 has a dc psu running at between 15Vdc and 25Vdc depending on mains and transformer.

The regulators of the DCB1 take that raw DC supply down to ~10Vdc into feed to the signal processing transistors.

If you think your DCB1 has 30V on the 2 little k170s then you have not looked at your schematic.
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Old 30th December 2012, 08:55 AM   #2580
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Hi everyone,

I've finished my Hypnotize B1, however it's not working now.

All Leds lit up, the current on one side is 40ma, on the other side, the current is 68ma.

I checked the voltage across the two 2SK170 for both channel, they're about 20.5V, so it seems that the voltage is correct. but I could not hear the relay click.

When I powered up, the green Led near the voltage regulator, lit up for half a minute then turned off completely.
I measured the voltage across the 10K bleeder resistor near the voltage regulator and saw that the votage dropped from 10V when powered up to 0v after 30"

I don't know if the voltage regulator (7812) working correctly? or something wrong?
Another thing is that since I did not have BC517, I replaced it with BC550.

Could you look into my problem and give me some advices.

Thank you very much!
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