Does it sound any better???
I'd be guessing that you are running a much lower va on that winding. You won't see voltage dips on a digital meter in any case. There is a reason for using a large va tx fir the servo section. It's greedy which is why the regs are getting warm!
With respect to the servo clock, you need half of the system clock if your clock can do it, you nee to send the feed to the xti or cki (clock in) pin. Check the device pin out at the start of the service manual.
@ben, id try reconnecting the servo to the original tx, disconnect the new tx from the mains and re test. Then connect the new tx to the mains only and re test. Then pair the tx output and re test. Then connect the centre tap to gnd and retest......you get the idea!!!
The base is slightly better
You are saying connect the servo supply back to the original and test with the winding to the 12V analog section disconnected
Then parallel the two windings for the 5V and servo, and test again right?
The clock I mean the clock for the decoder (16.934MHz), not the servo clock
Pin 13 is in Pin 14 is CRout
So I connect to 13 and ground 14?
Thanks
Does it sound any better???
I'd be guessing that you are running a much lower va on that winding. You won't see voltage dips on a digital meter in any case. There is a reason for using a large va tx fir the servo section. It's greedy which is why the regs are getting warm!
With respect to the servo clock, you need half of the system clock if your clock can do it, you nee to send the feed to the xti or cki (clock in) pin. Check the device pin out at the start of the service manual.
@ben, id try reconnecting the servo to the original tx, disconnect the new tx from the mains and re test. Then connect the new tx to the mains only and re test. Then pair the tx output and re test. Then connect the centre tap to gnd and retest......you get the idea!!!
The base is slightly better
You are saying connect the servo supply back to the original and test with the winding to the 12V analog section disconnected
Then parallel the two windings for the 5V and servo, and test again right?
The clock I mean the clock for the decoder (16.934MHz), not the servo clock
Pin 13 is in Pin 14 is CRout
So I connect to 13 and ground 14?
Thanks
The @ben bit was meant for Ben to help with his hum issue or at least to try and establish if it was there previously or at which point its introduced.
With respect your change, I am not aware of the spec's of the STD tx being available anywhere, but as said, I would guess that youre now running on a much lower va winding. As a matter of interest, did you previously bypass the fuses and use a large uF cap pre reg on the 5v side? These have a profound effect on the performance of the transport. I have to be honest and say it's not the way I would look to go. As said, it'll work but I'm fairly sure you'll be further choking the servo supply by using low va transformer windings. You need to keep an eye on the heat of the transformer as you could potentially be overloading the winding.
With respect your change, I am not aware of the spec's of the STD tx being available anywhere, but as said, I would guess that youre now running on a much lower va winding. As a matter of interest, did you previously bypass the fuses and use a large uF cap pre reg on the 5v side? These have a profound effect on the performance of the transport. I have to be honest and say it's not the way I would look to go. As said, it'll work but I'm fairly sure you'll be further choking the servo supply by using low va transformer windings. You need to keep an eye on the heat of the transformer as you could potentially be overloading the winding.
Those are the supply resistors to the opamps. Without them you'll not have the +/-12v to power them up. I'm surprised you're getting anything through!! I would put links in instead of resistors in any case
Make sure you remove r651-654 these will isolate the hdams from the rails. If you want to isolate the headphones from the audio also remove c901&902 and hook the opamp out too to get it off the supply rails (there are no supply resistors)
Make sure you remove r651-654 these will isolate the hdams from the rails. If you want to isolate the headphones from the audio also remove c901&902 and hook the opamp out too to get it off the supply rails (there are no supply resistors)
Those are the supply resistors to the opamps. Without them you'll not have the +/-12v to power them up. I'm surprised you're getting anything through!! I would put links in instead of resistors in any case
Make sure you remove r651-654 these will isolate the hdams from the rails. If you want to isolate the headphones from the audio also remove c901&902 and hook the opamp out too to get it off the supply rails (there are no supply resistors)
thanks ian beer takin over here il have a look in the am thx ur a star.
alan
Swapped the secondaries, but the hum is still there. The player sounds great otherwise. I wonder, could it just be my op-amps having a field day because I don't have resistors between them and the output RCAs? The hum and DAC noise is only audible at high volume with no output, and I've got an extremely sensitive amp.
I fitted all three transformers and I'm enjoying the increase in detail and depth. My only other problem right now is no display again. There's not too much out there about fitting the display tx. I think I've done it correctly as per Brent's guide, but I've got nothing coming through to the regulator again. The PCB traces are really flakey there for some reason. Beer taking over here too, so just enjoying the music now sans display.
I fitted all three transformers and I'm enjoying the increase in detail and depth. My only other problem right now is no display again. There's not too much out there about fitting the display tx. I think I've done it correctly as per Brent's guide, but I've got nothing coming through to the regulator again. The PCB traces are really flakey there for some reason. Beer taking over here too, so just enjoying the music now sans display.
The clock signal is presently supplied to pin 28 of the DAC. The transport works. But when I transferred the clock signal to pin 13 CRIN of the decoder and ground pin 14 CROUT the transport will not work
Errrrm! 07 p122 is a subcode error.
Compact Disc subcode - Wikipedia, the free encyclopedia 
Were you modding prior to your dilemma Alan?
Compact Disc subcode - Wikipedia, the free encyclopedia
Were you modding prior to your dilemma Alan?
Errrrm! 07 p122 is a subcode error.
Compact Disc subcode - Wikipedia, the free encyclopedia
Were you modding prior to your dilemma Alan?
No only mods are opamps it stands for long peirods tho its not my main player.
just pulled it out to have a listen.
cheers alan
C521 is a 10 pf cap. Lifted one leg and fed the clock signal
It works
Pre 5V regulator caps replaced with 22000uf and 4700uf
Supply regulated with 7809 and 7909
+8.88V and -9.24V measured
Is the difference in voltage critical?
Thanks Brent
Thanks Brent
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Try fitting a 470uF cap after the 7809 and see if that voltage increases. I run mine on +/-12V. Also check the supply voltage to the 7809. It will work but it would be better if it was closer to the 9V.
Now it works change the 10pF cap for a Silver Mica and solder it closer to the decoder for further improvements
Brent
Now it works change the 10pF cap for a Silver Mica and solder it closer to the decoder for further improvements
Brent
what are the voltages pre reg?
I've previously run mine on +/-8v regs when they are running off the original supply as I think the rails may not have enough headroom for 9v. Depends on the reg drop out. Looking at the OnSemi 7809 datasheet, you need 2v drop out.
In the main player, i've got a separate TX & PSU and so use 3 pairs of 12v SPowers the same as Brent.
I've previously run mine on +/-8v regs when they are running off the original supply as I think the rails may not have enough headroom for 9v. Depends on the reg drop out. Looking at the OnSemi 7809 datasheet, you need 2v drop out.
In the main player, i've got a separate TX & PSU and so use 3 pairs of 12v SPowers the same as Brent.