Monica dac questions

[merlin2049er]

Hi, I've got a few problems with my monica dac (original) that I've been wiring up myself.

I wired up the LM317 backwards and applied power (I'm just hoping I didn't blow the DAC)  (When I did power it up it made a bunch of buzzing and clicking noises.)

I got it wired up correctly now, and Yeo help me determine that the 22ohm resistor is also connect to the 1st pin on the LM317.   Now I'm getting the correct voltage ~4.5v to the DAC - but it's dead - no sound out of it. 

I've got a spare chip, I'll plug that in. 

Any other suggestions?

[yeo]

does it work with the spare chip?

[merlin2049er]

No.   I've got 2 dac chips. 

I get pops and clicks from one and nothing out of the other.

I'm hoping that the receiver (chip) isn't toast either.


So where can I get a pair of TDA1545s?

[merlin2049er]

Hey Yeo,

just wondering if it would be easy to add a usb interface to this board that's already wired up?

I can remove the SPIF input and CS8614 and go straight into the dac just with the usb right?

I think I prefer to go the usb route with this dac - it would save me from buying another usb transport.  (lol) 

[yeo]

your dac still doesn't work? you sure it's the analog stage? how about the digital circuitry?

if your cs8416 is working fine, pin 2 of tda1545 should measure 44.1khz.

usb requires a different chip, like say pcm2706 or pcm2707. problem is these chips output i2s of which you need to convert eiaj format as required by tda1545.

yeo

[merlin2049er]

No, it still doesn't work.

I've got a monica dac that works.  I'll pop the dac chips in that unit to find out if I burnt them out.  I'm sure that the digital receiver is ok.  (So you suggest I put a scope on pin 2 to find out if it's getting 44.1khz signal)?

[yeo]

if you have a scope, that's best to confirm digital signals are reaching pins 1-3 of tda1545.

if you don't have a scope, you could use your multimeter to measure frequency at pin 2 of tda1545. it should measure 44.1khz.

pins 1 and 3's frequency is way beyond the capability of a handheld multimeter.

yeo