I don't have a "removed 5334" version. You need to work that out.
Offset can be set very low and it holds steady once fully warmed up.
As is usual it wanders quite a bit during warm up.
Some of that is hidden while the output relay is open.
Offset can be set very low and it holds steady once fully warmed up.
As is usual it wanders quite a bit during warm up.
Some of that is hidden while the output relay is open.
Also when I replace the pots tomorrow, the 470r pot is being replaced with a 500r multi turn unit will that be a problem or does it have to ba a 470r ??
Regards
Danny
Regards
Danny
I am planning on finishing them tomorrow so any feed, info and anything else is very important! Please I am desperate to get them finish and sounds the best they have ever been!! Please note post 63 and 64!! And all others I have posted
Kindest Regards to all
Danny
Ps Anderw do you have a number I can txt or call on tomorrow if I need any help which I am hoping I don't!!
Kindest Regards to all
Danny
Ps Anderw do you have a number I can txt or call on tomorrow if I need any help which I am hoping I don't!!
the pins won't fit.Also when I replace the pots tomorrow, the 470r pot is being replaced with a 500r multi turn unit will that be a problem or does it have to ba a 470r ??
Regards
Danny
Use some short wire links.
Check that you turn it in your desired direction to increase the result.
I like clockwise to increase.
Some builders don't check.
My Email is switched ON.
Does the 30r difference not matter to the circuit? I thought it would be ok as it's the closest they do 500r original was 470r but looking at the circuit I wasn't sure it would affect anything because of the way it's connected in the circuit??
Regards Danny
Just about to start!!!
Regards Danny
Just about to start!!!
the difference is only 6.4%
The tolerance could be +-10%. It does not matter.
Now look at the trace side and you will see that two leads of the VR are connected together.
This converts the potentiometer to a variable resistor.
Turn the 500r down to 470r and for the remaining 94% of the rotation, it will behave just like a 470r variable resistor.
And just as a check, measure the two pots to find out whether they are different in maximum value.
The tolerance could be +-10%. It does not matter.
Now look at the trace side and you will see that two leads of the VR are connected together.
This converts the potentiometer to a variable resistor.
Turn the 500r down to 470r and for the remaining 94% of the rotation, it will behave just like a 470r variable resistor.
And just as a check, measure the two pots to find out whether they are different in maximum value.
Hi AndrewT ,
for the second time I heave a pair of p128 at home , first time I removed the OPa , as I thought there were a complete differential amplifier behind , modified the feedback loop to get the gain lost , removed the CCS in the firt stage ,this time I would create a dedicated power supply for Vamp and sort some problems of reliability. I already did a partial reverse for some sections of interest , but would you share your reverse eng with me ? I could'nt find on the Forum
And a few days ago , I found on the web a complete sheme of P128 .
If you don't have already , I could send to you .
regards,
for the second time I heave a pair of p128 at home , first time I removed the OPa , as I thought there were a complete differential amplifier behind , modified the feedback loop to get the gain lost , removed the CCS in the firt stage ,this time I would create a dedicated power supply for Vamp and sort some problems of reliability. I already did a partial reverse for some sections of interest , but would you share your reverse eng with me ? I could'nt find on the Forum
And a few days ago , I found on the web a complete sheme of P128 .
If you don't have already , I could send to you .
regards,
It would be helpful to a post a link to that schematic because this topic recurs and people still have difficulty finding AndrewT's posted schematic for a variety of reasons including ESL status, weak search engine and skills etc.- not just laziness.
http://www.diyaudio.com/forums/soli...fuse-output-offset-post844095.html#post844095
Note:this is zipped in an MS Word doc. file which you need to open it.
http://www.diyaudio.com/forums/soli...fuse-output-offset-post844095.html#post844095
Note:this is zipped in an MS Word doc. file which you need to open it.
My own sch is accurate, but is not the best layout to make it easily readable.
Sugden have at least two sch that "explain" the circuit better than my attempt.
Sugden have at least two sch that "explain" the circuit better than my attempt.
Have you looked up the datasheet for the relay driver devices.
I used a transistor & diode symbol there.
I used a transistor & diode symbol there.
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