Does this indicate an serious issue? MTS3200

[JustinCorrigible]

I have had an MTS3200 combo for 15+ years (and unused for the majority of those), I figured I’d remove the chassis and explore what’s inside, and maybe there is something I can learn along the way. I noticed something that didn’t look right.

I am less than a total beginner in this realm, but it looks like there’s been some overheating at those resistors between V2 and V3. What would be telltale signs to tell of a problem there if I hadn’t opened this up? I’ve never experienced any issues that I could ever tell (other than underwhelming gain that took me to the V3 model). I plugged it in last week to test it thinking I could maybe sell it, and it sounded as expected.

 

[griff10672]

I would definitely check those components out with a MM ...

I can't zoom in on the schematic you're showing to see what they are doing / attached to

you could simply replace them ... but the question is ... do they look like that just from getting hot over the last 15 years .... or is something somewhere else causing them to heat up like that ..... it looks like a failure of some sort to me ....

 

[JustinCorrigible]

I would definitely check those components out with a MM ...

I can't zoom in on the schematic you're showing to see what they are doing / attached to

you could simply replace them ... but the question is ... do they look like that just from getting hot over the last 15 years .... or is something somewhere else causing them to heat up like that ..... it looks like a failure of some sort to me ....

Ah, that schematic is kinda low res I see now… sorry. I would not expect them to get that hot, I mean I’ve barely ever played it in the last 15 years and certainly not a high volumes — cannot say from previous owner before me as this was 2008 when I picked it up.

It looked like some failure to me. I’ve got a multimeter, but without knowing what values to look for I’m just gonna look like a background character on CSI.

 

[griff10672]

put your MM on the diode test setting ..... check those diodes ... see if they are blown

then check your resistors with the resistance setting ... R29 and R30 ....

I found a copy of the schematic I can zoom in on ... R29 and 30 are suppose to be .56 Ohm

they are in the part of the circuit for the DC Heaters they come in last right before the tube filaments

the resistors might test funky because they are in circuit .... but they also might test as a straight up " short "

obviously make sure you know that there isn't any voltage present in the amp before you go poking around

 

[JustinCorrigible]

put your MM on the diode test setting ..... check those diodes ... see if they are blown

then check your resistors with the resistance setting ... R29 and R30 .... look like 5K the bands look like green , black , silver .. gold ( pretty sure that's 5k)

the resistors might test funky because they are in circuit .... but they also might test as a straight up " short "

obviously make sure you know that there isn't any voltage present in the amp before you go poking around

Thanks, I will attempt when possible.

 

[griff10672]

I edited my post ... see above