Re: Re: Really joyfull
Hope your new home is according to youe expectations.
I really do like the spower...... If I could, (€€€) I would replace ALL regs by those.
Now I am collecting parts for the dedicated PSU for analog dac and digital dac.
I have been looking to your pics and see you are using 10000uF BHC Aerovox ALT22A103CB040.
Looking ate the specs, I found that ESR is a bit high (50mohm).
Can I use two Pana FC 25v 4700uF instead ? (ESR is much better at 15mohm each and I would get a much higher ripple current at 7.5A combined)
Best Regards
Ricardo
Hi Brentrowemeister said:
I'm glad you like the reg
Hope your new home is according to youe expectations.
I really do like the spower...... If I could, (€€€) I would replace ALL regs by those.
Now I am collecting parts for the dedicated PSU for analog dac and digital dac.
I have been looking to your pics and see you are using 10000uF BHC Aerovox ALT22A103CB040.
Looking ate the specs, I found that ESR is a bit high (50mohm).
Can I use two Pana FC 25v 4700uF instead ? (ESR is much better at 15mohm each and I would get a much higher ripple current at 7.5A combined)
Best Regards
Ricardo
Hi Brentrowemeister said:
That settles it then.... I will need two BHC.
Now about the Spower... Can you please inform waht is the ic that looks like a reg ?
It is the same size but all plastic and I can not read any lettering.
I believe the trick in these regs is the speed they can deliver but I know nothing about it´s layout (secret is businesse´s soul!!)
Regards
Ricardo
output resistance
Once again asking the forum and members for help .. the problem is this.
The left channel has sounded ' soft for a while on checking resistance at rca's found 100k on right side, from r662 i think but 34k on left. Aha i thought r661 gone , got 34k across that... changed it but no improvement. Sounds simple so far.. removed link u217 to isolate output filter.. fine 100k now at L rca. Have since checked every component i can think of and can not find the cause. I guess its painfully obvious to some but cant nail it. I suspect some parallel path to ground coz on the dmm the 34k slowly rises as if charging a cap, so c611/613 have been out to check and ok as are the bypass caps
If anyone can point me in the right direction i will be most gratefull.
Many thanks in advance.
Ian
p.s.
It's a fairly well modded 67
also get on op amp pin 6 to ground 128k R, 47k L -- pin 7 to ground 100k R, 34k L. ??
Once again asking the forum and members for help .. the problem is this.
The left channel has sounded ' soft for a while on checking resistance at rca's found 100k on right side, from r662 i think but 34k on left. Aha i thought r661 gone , got 34k across that... changed it but no improvement. Sounds simple so far.. removed link u217 to isolate output filter.. fine 100k now at L rca. Have since checked every component i can think of and can not find the cause. I guess its painfully obvious to some but cant nail it. I suspect some parallel path to ground coz on the dmm the 34k slowly rises as if charging a cap, so c611/613 have been out to check and ok as are the bypass caps
If anyone can point me in the right direction i will be most gratefull.
Many thanks in advance.
Ian
p.s.
It's a fairly well modded 67
also get on op amp pin 6 to ground 128k R, 47k L -- pin 7 to ground 100k R, 34k L. ??
Hello Lee
Yes all resistors check out ok there is just such a massive difference when testing between components and ground on the L & R channels, also the L side when checked any readings are not constant and rise steadily as if charging a cap. Its as if there is a 60k parallel path.. and i cant find it.
many thanks Ian
Yes all resistors check out ok there is just such a massive difference when testing between components and ground on the L & R channels, also the L side when checked any readings are not constant and rise steadily as if charging a cap. Its as if there is a 60k parallel path.. and i cant find it.
many thanks Ian
Re: A minor update
Hi
I am seriously considering this mod that I believe must produce outstanding results.
My CD53 has LM4562NA opamps fed by a dedicated analog PSU.
Can I remove U205 and U206 and link here the Analog GND of the dedicated psu ?
Can this GND be left unconnected from the main PCB GND ?
(Must I will also isolate the output plugs so no connection will be left ?)
What are the pitfalls of such arrangement ?
Is it dangerous to isolate the GND circuits ? Can I expect some kind of dc offset ?
Regards
Ricardo
avr300 said:
Hi
I am seriously considering this mod that I believe must produce outstanding results.
My CD53 has LM4562NA opamps fed by a dedicated analog PSU.
Can I remove U205 and U206 and link here the Analog GND of the dedicated psu ?
Can this GND be left unconnected from the main PCB GND ?
(Must I will also isolate the output plugs so no connection will be left ?)
What are the pitfalls of such arrangement ?
Is it dangerous to isolate the GND circuits ? Can I expect some kind of dc offset ?
Regards
Ricardo
TCA0372 substituting
Hi.
My CD53 had a problem, first it worked all fine and in the next moment it started to pull drawer back and spin disc at very high rate. My first thought was that TCA0372 which operates the drawer and disc motor has come to its end. Well, after all I found out it was the that chip exactly(QM01), but it had burned also resistor R164.
Then I had trouble sourcing TCA0372, I began to look for substitute and after searching for a long time I found one which could substitute it; L2720. And it did!
This chip has some lower operating voltage range which has no meaning in this application because it still operates in specs. And slightly higher typical slew rate
So my point is that if someone else is having trouble sourcing TCA0372, you can substitute it with L2720.
-Antti
Hi.
My CD53 had a problem, first it worked all fine and in the next moment it started to pull drawer back and spin disc at very high rate. My first thought was that TCA0372 which operates the drawer and disc motor has come to its end. Well, after all I found out it was the that chip exactly(QM01), but it had burned also resistor R164.
Then I had trouble sourcing TCA0372, I began to look for substitute and after searching for a long time I found one which could substitute it; L2720. And it did!
This chip has some lower operating voltage range which has no meaning in this application because it still operates in specs. And slightly higher typical slew rate
So my point is that if someone else is having trouble sourcing TCA0372, you can substitute it with L2720.
-Antti
Re: Re: A major update
After taking a good look at the schematic, I know it is pointless to remove U205 and U206....
C611 612 613 614 are connected in the inner line..... Of course I could cut the GND line that goes to U201 but........
One question remains:
Is it dangerous to isolate the GND circuits ? Can I expect some kind of dc offset ?
Anyone care to comment ?
Regards
Ricardo
HiRCruz said:
After taking a good look at the schematic, I know it is pointless to remove U205 and U206....
C611 612 613 614 are connected in the inner line..... Of course I could cut the GND line that goes to U201 but........ One question remains:
Is it dangerous to isolate the GND circuits ? Can I expect some kind of dc offset ?
Anyone care to comment ?
Regards
Ricardo