I used...
MOSFET for my B-II. With two green leds and one 220R for Vref (no trimmer) I got just about perfect 5.3 volt output. Used a Silmic II 220 uF for Vref filter, and the sound is fantastic. Have not tried BJT, but really no reason to for me.
Remember this is just a pre-reg in this case, so the onboard regs will probably have more effect on the final sound.
MOSFET for my B-II. With two green leds and one 220R for Vref (no trimmer) I got just about perfect 5.3 volt output. Used a Silmic II 220 uF for Vref filter, and the sound is fantastic. Have not tried BJT, but really no reason to for me.
Remember this is just a pre-reg in this case, so the onboard regs will probably have more effect on the final sound.
YES, I changed Tridents for BiB BJT positive
very important each reg with is own tx (quality tx very audible so better R-Core minimum for clock reg)In the BIB instruction there is a description
".....Current draw: 100mA minimum ..."
is it caused by the power disspation limitations of the Q206;Q106;Q306 ???
or it's another reason for such limitations ?
If the circuit power demand is around 10-20mA (one side[+ or -] ; one chanel) can I use BIB shunt regulator , making CCS around 100mA ???
(considering the fact I would use 4 regulators separately for each channel , each supply side )??
".....Current draw: 100mA minimum ..."
is it caused by the power disspation limitations of the Q206;Q106;Q306 ???
or it's another reason for such limitations ?
If the circuit power demand is around 10-20mA (one side[+ or -] ; one chanel) can I use BIB shunt regulator , making CCS around 100mA ???
(considering the fact I would use 4 regulators separately for each channel , each supply side )??
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YES, I changed Tridents for BiB BJT positive
After Merlin el Mago's glowing report on replacing buffalo tridents, I threw together a 3.3V BiB without measuring K117 Idss or LED Vf.
Russ says the tridents R4 sets the max current (the 3.3V versions use 20R so: 1.2V/20R=60mA), but actual circuit draws as reported by Nicmac are:
VDD (1.2V): 90-115 mA
DVCC (3.3V): 16 mA
VDD_XO (3.3V): 13 mA
Based on that info I used a 39R dummy load (3.3V/39R=85mA), R101 set at 12R (1.96V/12R=163mA), one Red LED + 238R in Vref area, three green LED's.
Stable 3.3V with small 10gram Al heatsinks (40degC). I've yet to hook it up though.
The manual says BJT can provide as low as 2.5V output. Is there a way to achieve 1.2V?
Thanks to Salas and TeaBag for this cool project. I have a 4wire Kelvin ohm meter that is super accurate and now I can see why.
You can push your luck by using just a 1N4003 etc. diode as Vref I guess. Or just a 500R trimmer. 2.5V is the limit if with only one 1.9V LED as it normally uses and it contains its error amp voltage needs decently. I don't expect the Zo performance to remain intact when the error amp and its CCS Jfet will be squeezed at their very limit, but it could be passable. Vin must not be lower than what the 3 LEDs drop plus ~1V even if you will go very low Vout, by the way.
1.2V Vout
Thanks for the info about Tridents consumption so I can adjust accordingly because I need to reduce the hot at the maximum inside the box.
For 1.2V I use Salas SS1Vs regulator as per Disco's schematic
Thanks for the info about Tridents consumption so I can adjust accordingly because I need to reduce the hot at the maximum inside the box.
For 1.2V I use Salas SS1Vs regulator as per Disco's schematic
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Haven't you read post #1! jeez....
Legato is back to normal. I had swapped some Panasonic ECHU SMD films (.1uF) into it for decoupling in place of the electrolytics as an experiment. One or more of theses caps were possibly damaged from heat or I still had some flux trapped underneath causing a partial short. Put the 'lytics back in there and it's alright now. DC-in to the regs powering Legato is too low, I'll have another R-core here soon to fix that problem (18VAC x2). Tridents still not installed as I don't want to change too many things at once as I get a handle on all of this.
Legato is back to normal. I had swapped some Panasonic ECHU SMD films (.1uF) into it for decoupling in place of the electrolytics as an experiment. One or more of theses caps were possibly damaged from heat or I still had some flux trapped underneath causing a partial short. Put the 'lytics back in there and it's alright now. DC-in to the regs powering Legato is too low, I'll have another R-core here soon to fix that problem (18VAC x2). Tridents still not installed as I don't want to change too many things at once as I get a handle on all of this.
My 37V double mono Bibs just for fun.
P.S. How do I set the correct current?
Congrats Nick very neat & professional work
Wich main filter caps are you using, Mundorfs, wich model capacitance & voltage?
I see you are using some Mark teflon caps in RIAA paralleled with polysterenes
Zobel caps are Solen?
The output caps are Mundorfs silver?
My 37V double mono Bibs just for fun.
P.S. How do I set the correct current?
Nice build Salas
A new riaa Build ?
I like the two PSU lines
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Congrats Nick very neat & professional work
Wich main filter caps are you using, Mundorfs, wich model capacitance & voltage?
I see you are using some Mark teflon caps in RIAA paralleled with polysterenes
Zobel caps are Solen?
The output caps are Mundorfs silver?
Its the Mlytics the black with gold accent (more of those in the psu box too and 2x120VA Rcore), the output is the silver/gold/oil. Its a double mono for an audiophile friend. And he bought expensive stuff to make it. Full of Z-Foils etc.
Haven't you read post #1! jeez....
Legato is back to normal. I had swapped some Panasonic ECHU SMD films (.1uF) into it for decoupling in place of the electrolytics as an experiment. One or more of theses caps were possibly damaged from heat or I still had some flux trapped underneath causing a partial short. Put the 'lytics back in there and it's alright now. DC-in to the regs powering Legato is too low, I'll have another R-core here soon to fix that problem (18VAC x2). Tridents still not installed as I don't want to change too many things at once as I get a handle on all of this.
Much work fixing. Hope you are near to testing.
I like the two PSU lines
Heavy duty, they can power stage monitors.
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I suspected that you use more psu caps because I see in your pic that you don't use rectifier diodes in the BiBs, are you using a MOX resistor to set the current? as you know there is a sensitive position for sound my 1st option Mills & my 2nd option Welwyn or Vishay / SFernice both vitreous enameled, a lot of better sound using them: checked lately in my Disco's 1.2V Vout & my Bib 3.3V Vout vs ceramic, MOX, Kiwame. What caps are you using for lytic Vref & for film Zobel? are them bypassed with teflons? The cable used between regs. & mm/mc RIAA is CAT5?
About mm/mc RIAA:
Wich is the gain?
Wich cart use your friend?
The other resistors are all Shinkoh?
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