There shouldn't be any side-effects. 40 ohm, 47ohm, 100ohm, that really shouldn't matter much in sound level. Volume should be just as loud as with the HDAM in place. In the original player, there's 2x 100ohm in series, so theoretically it should be louder now
Are you sure you have everything connected properly? Opamp output > 100 ohm > output socket
Ray
Hi all, I'm Steve. Yes, another one. I need some advice. I have upgraded the diodes to schottky and in doing so the display has ceased to function. I read somewhere on here another member had the same problem. I just need to know where to start looking as i'm a novice. The player works fine with great sound apart from the display. Any ideas welcome. Great forum by the way. Thanks, Steve
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Just clic Digital Source - diyAudio then "new thread". It's always nice to see good players back to life
Ok let's check Studiostevus work, sorry for ot Ray!
Ok let's check Studiostevus work, sorry for ot Ray!
Double checked it... I measured with DMM 100ohm between the start of the bypass and the RCA's, so should be fine. Maybe it's the new opamps that are a bit quieter.
So.. where do we stand:
- muting circuit removed
- muting caps gone
- Raygulators for the +/- 12V rails
- LM4562 opamps
- Bypassed HDAM
What's the best thing to follow?
Clock?
Or are there some more caps to remove/change (In a SE version) ?
So.. where do we stand:
- muting circuit removed
- muting caps gone
- Raygulators for the +/- 12V rails
- LM4562 opamps
- Bypassed HDAM
What's the best thing to follow?
Clock?
Or are there some more caps to remove/change (In a SE version) ?
Lee,
I would be very happy if you can tell me how you spiced your TDA1547
How do you know if it's balanced or not? I think it is as it looks symetrical...
Right now I plan on using an extrenal single opamps like top Analog Device or National Semi to do the work of the internal ones and the DOS it.
Again, I'm begging all you even if have different points of view (that makes us more rich!) on my http://www.diyaudio.com/forums/digi...7-tda1547-vs-tda1541a-r1-vs-sm5872-story.html ! Promise I won't do (too soon...) commercial break for my church again
Ricardo why not a new thread! That may be exciting =)
I was talking about PCM56 in the Denon.
And I wasn't talking about external op-amps, I was talking about the I/V opamps INSIDE the PCM56. You can take I-out before these or V-out after these as the both signals have output pins.
Just follow Ray´s list....
Next thing I would do is replace the stock 7805 main +5v reg by a LM340AT... That should give an overall boost right now.
Hi Steve,
You can check if the negative display voltage is present at Q851. It should have about -24V at the output.
Ray
No Display
Measured voltage at Q851 was -0.61v. I'm guessing a broken track or dry joint around the diodes. I measured voltage across the diodes and got no reading on a couple.
Steve
Ray,
Measured voltage at Q851 was -0.61v. I'm guessing a broken track or dry joint around the diodes. I measured voltage across the diodes and got no reading on a couple.
Steve
Hi Steve,
Hope it's a small problem. You should sort out the negative input voltage to Q851 first. The problem with these boards is, they sit in the player untouched for years, and after tweaking the trouble starts...
Ray
Right, got -17.5v at Q851. Broken tracks. But still no display. To be honest, although i'm learning fast, I think it's beyond me. Seemed to have hit a brick wall. For some reason, no voltage across D814, and both DN03/04. Any ideas! cheers, Steve
Hi all,
just got error 10 in service mode (radial), not sure what this means. Can anyone offer any ideas? Could it be related to swapping opamps.
thanks
Steve
Error 10 is a radial error. Nothing to do with output. The output should never have any baring on the service mode codes as it is an independant circuit from the servo, decoder, dac & cpu data loop.
Brent
Hi all,
just got error 10 in service mode (radial), not sure what this means. Can anyone offer any ideas? Could it be related to swapping opamps.
thanks
Steve
You'll probably have disturbed one of the two ribbon cables or a 5V rail. Measure for +5V at each chip (servo, decoder, DAC) and lightly fettle the ribbon from the transport to the main pcb whilst the player's on and see if you can get a response. To check the front ribbon - unplug it and turn the player on - it should read and play the disc, only with no display or controls.
Simon