CD-PRO2M Builder's questions and comments

tianguis · « **Reply #180 on:** 27 Apr 2005, 11:53 pm »

All:
Last week, I built a Scott Nixon DacKit. It transformed the CD-Pro2M. All the internal wire is VH Audio 28 AWG silver in cotton. It's powered by a 12v. SLA.
Last night, on a whim, I built a star-quad pure silver power cord (2x2x2x2, 22 awg., for an effective 16 awg.) for the CD-Pro. I used P&S 5166 HGX and Schuko connectors. It's been running only about 24 hr's and has considerably better resolution than Volex, AA Crump PC or VansEvers double Pandora. It's unshielded and ungrounded so far (don't try this at home!). I think I'll work on developing this with a ground, maybe shielded, although it's quiet.
I've housed the DacKit in a nice extruded Al chassis. It'll be at Phil's room at the HE Show tomorrow evening. Unfortunately, I was one of the last to receive a DacKit, which Scott won't be offering again until much later this year, apparently.

Regards,
Larry Welsh

ken_diyzone.net · « **Reply #181 on:** 4 May 2005, 12:47 am »

Here is an excellent link from one of the CD-PRO2 builder from UK.

http://hometown.aol.co.uk/daltoneng/index.html

Thanks
Ken

divo · « **Reply #182 on:** 9 Jun 2005, 08:34 pm »

I am now about to solder in the small transformer that go on the digital output PCB. The orientation of these is unclear. The schematic seems to show pin 2 should be on the coax connector side, but the website photos seem to show otherwise. Are these symmetrical, ie their orientation is not an issue?

PT914 · « **Reply #183 on:** 16 Jun 2005, 05:49 am »

Divo,

Ken must be out. There are two rounded corners to the transformer, these should match the pcb layout.

Philip

ken_diyzone.net · « **Reply #184 on:** 16 Jun 2005, 01:22 pm »

Divo,

Sorry, missed this question. Like Philip (thanks) said, “There are two rounded corners to the transformer, these should match the pcb layout”

RonR · « **Reply #185 on:** 2 Jul 2005, 02:41 pm »

Hi all,

I must add my congratulations to others here on the excellent quality of the CD-Pro2 kit.
I'm almost finished mine, but I have a small problem left to overcome. Here are the symptoms:

On switch on at the back panel, I get no LEDs lit on the VFD board, no VFD display, the sequential power-on board doesn't function, and the standby switch doesn't operate.

Almost in desperation, I set JMP2 to short the lowest 2 pins (default is the top 2, right?), on switch on at the back panel I get no LEDs lit on the VFD board, but the sequential power-on board switches on immediately, the VFD display works, I can play CDs, and use the remote control. The CD sensor must be OK, as I can play a 60-minute CD all the way through. The standby switch still doesn't operate.

I've checked and double-checked all components, all power supplies are giving the correct voltages, though the VFD supply had me flummoxed until I saw a post here that it had to be plugged into the VFD board to register the -22.5V!

All the functions that don't work appear to centre on U5, the 89C2051.
Am I barking up the right tree?

Cheers,

Ron.

SteveSun · « **Reply #186 on:** 2 Jul 2005, 03:01 pm »

Hi RonR: please check the toggle switch to the VFD PCB connection: pleas use only upper 2 inputs on the VFD PCB...

RonR · « **Reply #187 on:** 4 Jul 2005, 11:27 pm »

Hi Steve,

No luck with the switch I'm afraid. It was already wired push-up-to-make on the top two power inputs on the VFD board.
R37, the pull-up resistor is keeping the top input at 5V until the switch is thrown, when it drops to 0V. I have confirmed that this also happens at pin 2 of U5.

I've just carried out some further diagnostics, and:
D3, D4 and D5 never illuminate (5V on both anode and cathode)
The power-on switch board relays and LEDs always operate.
Removing J2 from the top 2 pins drops U2 pin 9 (reset) to 0V, the VFD display and the CD-PRO mechanism then burst into life.

EDIT: I checked the CD detection module this morning, and it's functioning normally.

Testing the pins of U5 with J2 shorting the top 2 pins gives:
1:0V 2:5V 3:5V 4:2.4V-12Mhz 5:2.2V-12Mhz 6-9:5V 10:0V
11:5V 12:N/C 13:1.8V 14:2.4V 15:2.4V 16:4.6V 17-20:5V

Testing the pins of U5 with J2 shorting the lower 2 pins gives:
all the same readings except pin 16:5V

Cheers,

Ron.

notusus2002 · « **Reply #188 on:** 13 Jul 2005, 12:53 am »

hmmm, my player exhibits faintly the same characteristics as RonR. CD does not read, LCD keeps flashing '--- ----' and the Power Sequential Module's D10 LED not lighted up (the other one is working though).

haven't plug in the CDPRO2 power yet.

measuring the Power Sequential Module's MOLEX pin for o/p voltage (this is the power to the CDPRO2) shows, 'GND, 9V, GND, ????'. 5V reading not available.

suspecting that it could be either LED, RELAY or 1N4148 diode problem, these were all changed to a new set but same results persist.

VFD PCB Resistors R2, R3, R4, R5 and R6 supplied are 51R1F. (the manual states 49R9F).

the following are the checks done:
- - - - - - - - - - - -
1. the AC input and output from the 9v Power Supply (21 vAC input, 9 vDC output) and 5v Power Supply (18vAC input, 5vDC output) modules checked and OK. LED on these 2 modules are working.

2. Digital Out PCB is getting measured 5 VDC from the power sequential.

3. CD detection sensor is working. Flashing red LED disappears when a CD is placed on the CDPRO2.

4. VFD Power Supply Checks. The DC output voltages were measured and the readings as follows:

a. GND: 0
b. +5
c. Non: -24
d. -24
e. -22.3
- - - - - - - - - - - - - -

haven't shifted the JMP2 to short the lower 2 pins like what RonR did. don't know if it's 'legal' unless Steve/Ken gives the green light for it; don't really wnat to destroy something.

could it be due to the 220VAC that both RonR and myself are using? damaged U5 chip on VFD?

appreciate if anyone out there can help.....really desperate now.

cheers
simon

ken_diyzone.net · « **Reply #189 on:** 13 Jul 2005, 01:37 am »

Hi Simon,

The parts that Steve suggested is in the mail already. Let's try them out and see if that resolve the problem.

RonR · « **Reply #190 on:** 13 Jul 2005, 08:11 pm »

Hi Simon,

I doubt if the 220/240V we are using is the culprit.

The fact that you have a flashing LED and it goes out when a CD is present means that in your case, U5 is probably OK.

From your description, it seems like your problem lies with Q3, R18, C13, or R17 on the VFD board, or in the cable and connectors between VFD J1 and Power sequence board CN1. Oh, and also check the continuity on the IC socket for U5 pin 15.
I would start checking at U5 pins 14 and 15, working my way towards the Power sequence board.

Cheers,

Ron.

notusus2002 · « **Reply #191 on:** 14 Jul 2005, 01:45 am »

i've checked the voltages on the 89C2051 (U5) while the display was turned on and these are the values:

Pin : Voltage
1 : 0v
2 : 4.97v
3 : 4.95v
4 : 2.45v
5 : 1.93v
6 : 4.94v
7 : 0.04v
8 : 1.65v
9 : 4.94v
10: 0v
11: 4.95v
12: 0v
13: 1.75v
14: 2.33v
15: 0v
16: 0.01v
17: 4.95v
18: 0.06v
19: 0.08v
20: 4.99v

Removed U5, reinserted in and measured again. Same voltages were obtained. Seems quite different from what RonR measured. Any comments.

RonR · « **Reply #192 on:** 14 Jul 2005, 07:08 pm »

Hi Simon,

From your measurements, it looks to me as if U5 is working correctly, except that the voltage on pin 15 looks suspect. Did you measure it at the printed circuit board, or on the leg of the chip? It might be worth doing both to see if there's a problem with the IC socket. The other possibility is that something is shorting pin 15 to earth further down the line. Maybe the leads of C13 are shorted?

Just my twopenny-worth!

Cheers,

Ron.

notusus2002 · « **Reply #193 on:** 18 Jul 2005, 05:31 pm »

howdy!

has anyone tried changing the caps (C7 and C11) on the 5v and 9v Power Supply Boards? this is the default recommendation by Ken/Steve.

how's the sonic outcome?

or has anyone tried any other cap combination?

cheers
simon

RonR · « **Reply #194 on:** 28 Jul 2005, 09:40 am »

Hi All,

I received a new Atmel chip (U5) in the post this morning from Ken, and after I'd straightened out the pins (do all postal workers sit on the mail?) I replaced the U5 on my VFD board.

BINGO! ---- All functions are now working as advertised.

I'd like to tone down that blue LED though, it seems to be about 4 times brighter than the green or red ones.

Cheers,

Ron.

RonR · « **Reply #195 on:** 28 Jul 2005, 01:53 pm »

Ken or Steve,

I've just seen this article on DIYZONE: http://www.diyzone.net/article.php?sid=603

Looks like the idea is to automatically reset the player when the CD enclosure is opened /closed.

Will it be offered as an upgrade?

Cheers,

Ron.

notusus2002 · « **Reply #196 on:** 28 Jul 2005, 03:49 pm »

hip hip hooray!!!!!!!!!

at last there is light at the end of the tunnel

awating for my turn........

i think those blue LEDs are called 'ULTRA BLUE'......

ok, here's the low tech solution. try using a marker pen to tone down the intensity. i used a permanent Blue marker pen. altenatively, the LED can be changed to something less intense.

enjoy your CD PRO2!

JM · « **Reply #197 on:** 16 Aug 2005, 05:19 pm »

Just an update on my latest CD-PRO2M kit tweaks and modifications.
I've replaced the clock with a Tent Labs clock XO2 to the CD-PRO2M module. I've also added an independent power supply for the new clock. The results were shocking. I wasn't expecting such a big improvement. The whole sound presentation acquired more presence and depth. Detail and the ability to process complex passages have been improved as well. Tonality didn't change much, but the sound appears more analog, more natural.
I'm using the CD-PRO2M as a stand alone player, using its built in DAC and analog buffer. I've being thinking on how to better the buffer and the overall CD-PRO2M board. I replaced a few of the SMD caps on the board with some Black Gates I had on hand. That helped the sound quite a bit. But I should be replacing all SMD electrolytic caps with Sanyo OS-CON or Panasonic FK SMD caps. The analog coupling caps should be Auricaps if I can manage to solder them to the board. And for the buffer stage op-amp, now a ST TS462C, I'm looking for op-amps that can be fed by a single power supply (+5V) and that have better specs than the stock TS462C. The Analog Devices AD8028 sounds like a good candidate using a small 0.01uF NPO ceramic cap at the power input. Any op-amp suggestions for this application?
Ken, have you had any news from Taiwan regarding the I2S internal DAC?

ken_diyzone.net · « **Reply #198 on:** 19 Aug 2005, 07:39 pm »

Hi Julien,

No news on the I2S DAC and De-Jitter yet..

Occam · « **Reply #199 on:** 20 Aug 2005, 03:14 am »

Quote from: JM

... And for the buffer stage op-amp, now a ST TS462C, I'm looking for op-amps that can be fed by a single power supply (+5V) and that have better specs than the stock TS462C. The Analog Devices AD8028 sounds like a good candidate using a small 0.01uF NPO ceramic cap at the power input. Any op-amp suggestions for this application?
...

The AD8066 swings rather nicely through a +5v single rail with a goodly dollup of current. I'll leave the examination of specs to you, but will comment that subjectively the AD8066 lies between the OPA627(OPA2107) and the AD8010/20.

FWIW