[b0bb]

@Monolithic, I replaced A,B, C, and D with four LT1431 each in the same orientation as the previous ones were installed.

Parts C and D are not LT1431, put the original part back in.

 

[leondikim]

Oops.. okay. Then what are these?

 

[b0bb]

Oops.. okay. Then what are these?

Part of the LED based voltage reference for stage-1 of the regulator, this most likely why the LED went out.

 

[leondikim]

It works after putting back the original parts on C and D! Thank you so much @b0bb and @Monolithic !!

 

[Gilberto 62]

Good afternoon guys. Please, a short and simple question: how do you recommend connecting a cd player to the dac, by coaxial or by optical ...? I guess by optical but I prefer your advice. Thanks...

 

[Monolithic]

@b0bb

* Does the LT1963A/LT1764A (A) only supply power to the XO regulator (B)?

* What supplies power to the LT1963A/LT1764A?

Thanks again.

 

[Xoverman]

@b0bb

* Does the LT1963A/LT1764A (A) only supply power to the XO regulator (B)?

* What supplies power to the LT1963A/LT1764A?

Thanks again.

Yes
Y & S

 

[b0bb]

@b0bb

* Does the LT1963A/LT1764A (A) only supply power to the XO regulator (B)?

* What supplies power to the LT1963A/LT1764A?

What @Xoverman said

 

[b0bb]

Good afternoon guys. Please, a short and simple question: how do you recommend connecting a cd player to the dac, by coaxial or by optical ...? I guess by optical but I prefer your advice. Thanks...

Use coax if your CD player was made before 1996, make sure to use proper 75ohm coax cable.
LKS paid more attention to coax than optical on the 004.

Before 1996, optical spdif was proprietary to Toshiba, top end units used optical transmitters from Toshiba, performance is ok if your player used the Toshiba optical interconnect known as TOSLINK.
Cheap CD players copied this with variable degrees of success, I usually avoid using optical spdif on old players if output module not made by Toshiba.

DVD came to the market in 1996, this pushed manufacturers to standardize and fix optical spdif problems from past years and improve the jitter performance.
TOSLINK was one of Toshiba's contributions to the DVD standard.

 

[Monolithic]

@b0bb Just for clarification, the LT3042 (200ma) [regulator "B"] supplies 3.3V to the XO (120ma for Pulsar XO) and supplies 3.3v to the VCCA of each of the 9038s (3ma x 2)?

 

[b0bb]

@b0bb Just for clarification, the LT3042 (200ma) [regulator "B"] supplies 3.3V to the XO (120ma for Pulsar XO) and supplies 3.3v to the VCCA of each of the 9038s (3ma x 2)?

Yes.

Keep in mind VCCA is one of the first supplies that must reach a stable state for the 9038 to reset properly if you are thinking about modding this regulator.

 

[Monolithic]

Yes.

Keep in mind VCCA is one of the first supplies that must reach a stable state for the 9038 to reset properly if you are thinking about modding this regulator.

@b0bb - I'm assuming that cset cap value is at the lower end (0.47uF) with a start up time of under 50ms (3.3v instead of 5V).

LT3042 Start-Up Time

VOUT(NOM) = 5V, ILOAD = 200mA, CSET = 0.47μF, VIN = 6V, VPGFB = 6V - 55ms
VOUT(NOM) = 5V, ILOAD = 200mA, CSET = 4.7μF, VIN = 6V, VPGFB = 6V - 550ms
VOUT(NOM) = 5V, ILOAD = 200mA, CSET = 4.7μF, VIN = 6V, RPG1 = 50kΩ, - 10ms
[RPG2 = 700kΩ (with Fast Start-Up to 90% of VOUT)]

 

[b0bb]

@b0bb - I'm assuming that cset cap value is at the lower end (0.47uF) with a start up time of under 50ms (3.3v instead of 5V).

LT3042 Start-Up Time

VOUT(NOM) = 5V, ILOAD = 200mA, CSET = 0.47μF, VIN = 6V, VPGFB = 6V - 55ms
VOUT(NOM) = 5V, ILOAD = 200mA, CSET = 4.7μF, VIN = 6V, VPGFB = 6V - 550ms
VOUT(NOM) = 5V, ILOAD = 200mA, CSET = 4.7μF, VIN = 6V, RPG1 = 50kΩ, - 10ms
[RPG2 = 700kΩ (with Fast Start-Up to 90% of VOUT)]

Yes, this is why LKS used the lower values, quite sloppy of LKS as the 3042 has provision for fast start.

550ms delay with 4.7uF w/o fast-start is terrible.

 

[Gilberto 62]

Thank you very much, b0bb, for your answer...

 

[leondikim]

@b0bb - A few questions regarding upgrading to 1.3v on the Gen2 board:

1) Any reason to leave the C1/R1, C2/R2 pairs on the board after removing the regulators? I'm assuming C1/C2 are charge pump caps and R1/R2 are feedback/set resistors

2) For the input wire, did you run a flexible wire from the C3/C4 smd caps (yellow dots) to the Belleson regulators? I didn't know if two points of through hole support were enough to handle the heatsinks. Was thinking of possibly using a third stiff wire to the input cap through hole as well, but it appears to be a fair distance away (red dots indicate through hole mounting points). (C5/C6 along with output E-caps are moved onboard with respective Belleson regulators)

Thanks.

Hi, @Monolithic, Have you succeed to upgrade to 1.3v on Gen2?