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

Should be 130VDC. Check C916.

Leonard

"Dave Moore" wrote in message
.. .
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

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.


"Leonard Caillouet" wrote

: 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
:
:
:
:

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" wrote in message
.. .
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.


"Leonard Caillouet" wrote

: 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
:
:
:
:

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


"Leonard Caillouet" wrote in message news:LDOAe.35717$up5.3516@lakeread02...
: 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" wrote in message
: .. .
: 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.
:
:
: "Leonard Caillouet" wrote
:
: : 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
: :
: :
: :
: :
:
:
:
: