am sticking with the Silimic IIs for Vref. I am using Mundorf MKP (4.7uF) for the Zobel cap.
I have not done any listening with these, as I will need to do some re-drilling of my chassis, and a little other re-wiring (and probably a new difgital side transformer, as I need 2 x 9 Vac out for DAC and USB interface power). So it will be a little while before I do any listening. I have just been fine tuning for voltage and current. As the B-II is a popular devise, I just wanted to give people some starting points in values.
Agreed, thanks for sharing.
I will try to get an entry into my blog with some numbers for the Buffalo's. There quite a few people buying these for them.
If other popular projects or voltages come up, feel free to give me the LED, and R value details.
They will ask me or Salas, and Salas will tell them to break out the calc
Marra,
Selectronic is very lousy in replying emails from my experience (2-3 days delay). But shipping good and fast. Maybe a bit pricey for my country (20eur.)
That's why I've turned to these guys hifispot168 | eBay. Nothing to complain and it came faster then expected.
Thanks for the link unfortunately they no longer seem to be in business!
Selectronique I have emailed twice in the past month in both English and French but they still not replied. Guess I could try phoning.
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With first +- regs I reached +-24Vout very easily but the second +- regs the posistive rail I get max +24Vout with trimmer at each max position & after warm up, negative rail only I get max -23.6Vout with trimmer at max. position, I'm using in all regs:
Tx 24VAC - 0 - 24VAC 120VA so 60Va per winding
PSU 10.000uF 63VDC Jensen 4 pole caps
Vin at the reg -33,7VDC
Load 1K 5W
R1 3R9 1.5V across (384mA)
I used two differents Tx with the same results
I don't understand the reason because first +- reg was operating OK without any problem at first attempt
Tx 24VAC - 0 - 24VAC 120VA so 60Va per winding
PSU 10.000uF 63VDC Jensen 4 pole caps
Vin at the reg -33,7VDC
Load 1K 5W
R1 3R9 1.5V across (384mA)
I used two differents Tx with the same results
I don't understand the reason because first +- reg was operating OK without any problem at first attempt
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With first +- regs I reached +-24Vout very easily but the second +- regs the posistive rail I get max +24Vout with trimmer at each max position & after warm up, negative rail only I get max -23.6Vout with trimmer at max. position, I'm using in all regs:
Tx 24VAC - 0 - 24VAC 120VA so 60Va per winding
PSU 10.000uF 63VDC Jensen 4 pole caps
Vin at the reg -33,7VDC
Load 1K 5W
R1 3R9 1.5V across (384mA)
I used two differents Tx with the same results
I don't understand the reason because first +- reg was operating OK without any problem at first attempt
Add a resistor into diode position, or swap out the R203 for something larger.
I don't understand the reason
The reason is something's smaller in the reg that can't go 24V. If the resistors are the same, then simply the K117 in the lower Vo reg has less Idss than in the other reg. Add more resistance as Tea wrote. Simple Ohm's law.
gave it a dummy R load when I fired it up. using 10R at 301
turning the trimmer does not change the V either.
using a 18V AC tfo
Check that your Q103,203,303 are K117 JFETs and not BC transistors by mistake. Because one reason can be having no current to drive the V reference resistors and trimmers. What dummy value?
Suggested resistor value?
What resistor and trimmer you use now in the -23.6V max one?
I believe the suggested resistor value is 1K or less, right?
Tell me what you use now first, so I can calculate your current.
The guide writes 1K8 resistor also. Is that resistor 1K8? Anyway, add 1K instead of the Zener jumper, should give you enough conversion to reach 24V with ease.
P.S. I see you edited. The examples in the guides state they assume a certain in circuit IDSS. If a FET chances a bit weaker or stronger it takes compensation in the values.
P.S. I see you edited. The examples in the guides state they assume a certain in circuit IDSS. If a FET chances a bit weaker or stronger it takes compensation in the values.
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