It is a pitty this idea did not come along when I was at it.In my machine, the Servos are powered by the stock TX... And I am afraid to even open it up again now... Too complex.
Hi Gheorghes,
Nice work, you managed to squeeze quite some stuff in there!
C756 provides decoupling for internal circuitry, so by critical they mean you have to use a good cap, and the shortest possible connection so there's no additional noise introduced into this pin. Is it a standard electrolytic in there now?
3.3uF is the value that is sufficient for good operation of the DAC, but a larger cap means less ripple most of the times, so maybe a 10u BG with it's low impedance will improve things further. Just use your ears! Another good option is a 3.3uF film cap, like Wima MKS. They have even lower ESR and have very low leakage current, which seems an important factor at this particular pin.
So the verdict is: bypassing a good cap is a bad thing
Regards,
Ray
I have to replace the capacitors mainly with my CD6003 analog supply (35V 1000μ) with Mundorf (4700μ 40V). Should I bypass a film 4.7 μ?
Ray says: bypassing a good cap is a bad thing. is always the case?
thanks
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In my machine, the Servos are powered by the stock TX... And I am afraid to even open it up again now... Too complex.
You can do it all from the top!! just locate the links that run the unregulated supply. U161 and U162 will give you the supply to 2 of the drivers and U149 and U150 the final one!! You could add regs at the same time if you've not already done so.
In fact I know that the capacitors are used after the main film, capacitors 4.7UF. I would like some advice on what type to use. After Mundorf M-Lytic AG 4700 UF 40V The wima 4.7UF are ok?
Is a forum full of competent people and try to do things right.
thanks
It's not always the case... The Mundorf M-Lytic are not particulary low-ESR caps, so there could be some gain in bypassing them with a 4u7 film cap, to lower the impedance in the high-frequency region. Wima is fine, but any other A-brand is o.k. as well.
Ray
Hi , i have swapped out the mech with a donor cdp but still showing error 12.
Any thoughts-
All voltages supplying the driver ic-SA 0372 from extra power supply measures 11V/-11V.
checking service mode. The player motor is ok,the sled moving up and down .
But still saying disc?
Any thoughts?
Any thoughts-
All voltages supplying the driver ic-SA 0372 from extra power supply measures 11V/-11V.
checking service mode. The player motor is ok,the sled moving up and down .
But still saying disc?
Any thoughts?
I can only think something is amis arround the TCA0372 (should be +10v out) or the servo TDA130IT or even the decoder 7345, but i'm not very technical in this area. I was hoping someone with the knowhow would be along shortly to help. There a quite a few of them out there. I'm sure someone will be along soon. Regards Barry
Thanks for the help guys, yes i took out the xtal from servo and the assoc resistor. The new clock has 2 outputs which supply both the dac and servo and i grounded the servo xtal using its middle leg as per schematic,the input goes into pin 19 of the servo closest to the chip. The timezone difference is making it difficult as i need to head off to work now.
Will check the servo clock to make sure it is the right pin , or even swap it out to see.
Will report later ,many thanks
Quan
Will check the servo clock to make sure it is the right pin , or even swap it out to see.
Will report later ,many thanks
Quan
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In the absence of an oscilloscope to check, I would replace the original clock components and retest. Then add the clocks 1 at a time testing in between each change. Its a pain to keep getting the board in and out but its always best to test after each single mod. As I'm using an SE case with 2 baseplates, I've cut a hole in my chassis because its a nightmare to get the board in and out with all those regs and supplies!!!
On another note, here's a pic of the new modified CFP DOS in the player
On another note, here's a pic of the new modified CFP DOS in the player