Mitsubishi TV CS-3506 What is proper B+ voltage ? alt. ref: CS-3506R CS3506 CS 3506 C

[Dave Moore]

Hello,
I just fixed this Mitsu CS-3506 in a trade deal with
a friend of mine. Crikey after replacing every
Nichicon black cap with a " + " stamped into the
top of the can and also hours of reworking electrolyte
damaged traces I think I'm about ready to make the
drive and put the chassi back into the set.

Before I pulled the chassi out, I measured B+
to the HV section to be 149 V
None of the Mitsu schematics I have for other sets
indicate any B+ this high.
Could this be normal for this model,
or should I take a closer look at the SMPS
regulation before I reinstall the chassi
and fire this puppy up?

Thanks,
Dave

 

[Leonard Caillouet]

Should be 130VDC. Check C916.

Leonard

 

[Dave Moore]

Thanks Leonard,
I don't have the chassi handy but I'll lay odds
that C916 was probably one of the some 20
or more caps I replaced so maybe that problem
has already been fixed. I guess I'll try to power
up at least the SMPS on the bench and verify this.



: Should be 130VDC. Check C916.
:
: Leonard
:

: "Dave Moore" wrote
:
: > Hello,
: > I just fixed this Mitsu CS-3506 in a trade deal with
: > a friend of mine. Crikey after replacing every
: > Nichicon black cap with a " + " stamped into the
: > top of the can and also hours of reworking electrolyte
: > damaged traces I think I'm about ready to make the
: > drive and put the chassi back into the set.
: >
: > Before I pulled the chassi out, I measured B+
: > to the HV section to be 149 V
: > None of the Mitsu schematics I have for other sets
: > indicate any B+ this high.
: > Could this be normal for this model,
: > or should I take a closer look at the SMPS
: > regulation before I reinstall the chassi
: > and fire this puppy up?
: >
: > Thanks,
: > Dave
: >
: >
:
:

 

[Leonard Caillouet]

You will likely need to replace the regulator if the B+ is too high and the
caps are good. There is also a green ceramic in that PS that changes value,
IIRC. You might want to check.

Leonard

 

[Dave Moore]

Thanks for the heads up
I'll keep that in mind when I get back to it next week
as my plans for this week have been reordered so that
I might finish a new guitar amp design in time for another
friend before he starts recording his new CD this Saturday


: You will likely need to replace the regulator if the B+ is too high and the
: caps are good. There is also a green ceramic in that PS that changes value,
: IIRC. You might want to check.
:
: Leonard
:
: : > Thanks Leonard,
: > I don't have the chassi handy but I'll lay odds
: > that C916 was probably one of the some 20
: > or more caps I replaced so maybe that problem
: > has already been fixed. I guess I'll try to power
: > up at least the SMPS on the bench and verify this.
: >
: >
: >
: > : Should be 130VDC. Check C916.
: > :
: > : Leonard
: > :
: >
: > : "Dave Moore" wrote
: > :
: > : > Hello,
: > : > I just fixed this Mitsu CS-3506 in a trade deal with
: > : > a friend of mine. Crikey after replacing every
: > : > Nichicon black cap with a " + " stamped into the
: > : > top of the can and also hours of reworking electrolyte
: > : > damaged traces I think I'm about ready to make the
: > : > drive and put the chassi back into the set.
: > : >
: > : > Before I pulled the chassi out, I measured B+
: > : > to the HV section to be 149 V
: > : > None of the Mitsu schematics I have for other sets
: > : > indicate any B+ this high.
: > : > Could this be normal for this model,
: > : > or should I take a closer look at the SMPS
: > : > regulation before I reinstall the chassi
: > : > and fire this puppy up?
: > : >
: > : > Thanks,
: > : > Dave
: > : >
: > : >
: > :
: > :
: >
: >
:
: