Soundcraftsmen MA5002 Repair

[@Wil_Bloodworth]

Great information about the "quick test" on the output transistors. That will come in handy I'm sure. Thanks Ray!

[@raygianelli3612]

Wil, there's a limited number of instances where this will work. The amp has to be full complementary and have no protection relay. for amps with a relay, you can just clip onto an emitter resistor in lieu of the speaker jack.

[@Wil_Bloodworth]

@@raygianelli3612 understood. Thank you!

[@petercornell2002]

Thanks Ray, interesting amp.

[@raygianelli3612]

The power supply is really different. I worked on a similar one, and the power supply was a bear to troubleshoot due to its design... or just my lack of understanding it. 😆

[@cajuncoinhunter]

Old vintage stuff like that is hard to find .... I was raised on tube type stuff then solid state . Me , myself I don't really need the meters to achieve a balanced sound .... Great job on that diagnosis ..

[@raygianelli3612]

A friend told me that some guys are just in love with meters. Half the time I'm listening to music my eyes are closed, so it's not a big deal to me either. 😁

[@Douglas_Blake_579]

@@raygianelli3612 LOL ... guilty as charged. Love the dance and rhythm of the bouncing needles ...

[@briandeeley1599]

@@raygianelli3612 I remember back in the day Soundcraftsman ads all over the back section of Stereo Review magazine.

[@Douglas_Blake_579]

Nicely done, as always.

[@raygianelli3612]

Thanks Douglas. A little time off the bench was nice.

[@Douglas_Blake_579]

@@raygianelli3612 Nothing I enjoyed better than a day of "on the road" calls, just to get out of the office for a while. 😎

[@Edisson.]

Hi Ray great job as always👍 never seen meters corroded like this 🤔 must have been in a very humid environment 🤔 or they were cooling it with water 😂. Nice day 🙂Tom

[@raygianelli3612]

Hi Tom! Humidity is just brutal here. I run before sunrise to avoid the heat, but the humidity can reach up to 100%. I didn't know you can have 100% humidity without rain, but apparently you can.

[@Douglas_Blake_579]

Humidity + Nicotine are the usual culprits in this case. I also woldn't be surprised to find out that, at some point, the face of that amplifier was drenched in water.

[@payingcustomer6107]

Hi Ray! Out of curiosity, have you done any work to Parasound equipment?

[@raygianelli3612]

Yes. kzbin.info/www/bejne/aJaagaeQe6ikrc0

[@briandeeley1599]

Moist environments are not good for electronics, it looks like this amp was stored or used in a garage from the looks of that corrosion and the power transformer was rusty looking.

[@raygianelli3612]

I'm in South Florida, and rain and humidity are just brutal for 3/4 of the year. Even so, this one was worse than most I've seen.