MTX 8001

Andrey2016

Member
2016-05-02 12:00 pm
MTX TA81001

Hello! Maybe somebody know the name of D104 and D105? I can't find in the internet:eek: I replaced D105 on zener diode 15V Is it correct? I get +15 -14V and resistor R117 in -15v regulator became very hot. FET 191 have 1-18 2-80 3-15V in +15V regulator, but FET 192 have 1-69 2-14 3-80V in -15V regulator. Is it correct? Is FET 192 - Irf540? Please help:eek:
 
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Andrey2016

Member
2016-05-02 12:00 pm
I'm asked MTX about schematic but they could not help me. I replaced D105 on zener diode 15V Is it correct? I get +15 -14V and resistor R117 in -15v regulator became very hot. FET 191 have 1-18 2-80 3-15V in +15V regulator, but FET 192 have 1-69 2-14 3-80V Is it correct? And also FET 192 became very hot. Is FET 192 - IRF540? Please help!!!
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elchino10

Member
2010-12-23 7:14 pm
I'm asked MTX about schematic but they could not help me. I replaced D105 on zener diode 15V Is it correct? I get +15 -14V and resistor R117 in -15v regulator became very hot. FET 191 have 1-18 2-80 3-15V in +15V regulator, but FET 192 have 1-69 2-14 3-80V Is it correct? And also FET 192 became very hot. Is FET 192 - IRF540? Please help!!!
247124d73c8d.jpg
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Perry Babin

Member
Paid Member
2003-11-20 11:01 am
Louisiana
www.bcae1.com
It's generally best to post photos of your amp instead of photos you find elsewhere. It's sometimes saves time if you're inexperienced and miss some small detail.

It's best not to use a hyphen as a separator. It's difficult to tell where it's a negative or simply a separator.

Was the negative regulator clamped tightly to the heatsink when it was getting hot?

Leave the preamp board disconnected until all of the regulators are repaired. If one of the regulator FETs shorted, there is likely damage to the various op-amps and 10 ohm resistors on the board.

Side note, do not operate this amp without everything clamped tightly to the heatsink.
 

Andrey2016

Member
2016-05-02 12:00 pm
"it is a mmbd4148 diode just a normal diode" When I replace zener diode to normal diode then instead 14 became 69V. And R117 not heated, strange:(
" Was the negative regulator clamped tightly to the heatsink when it was getting hot?" Yes but R117 became very hot.
This is photo of my amplifier
1e3f52489228.jpg
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