Comet System 9 High Voltage Repair

Note:  This repair was initially published on Sept. 19, 2011.  I republished it with updated photos and information.

I received a call for a Comet with non-working displays.  I was told that there were no blown fuses, but the displays just stopped working.  No blown fuses indicates a problem with the power supply.  I was hoping this was the case as troubleshooting alphanumeric display problems is not a lot of fun in my book.

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Data East Sound Amp Repair

I was working on a Data East 520-5002-03 sound board that had no output to the cabinet speaker.  The cabinet speaker was blown, but there was still no sound output when using a known good speaker.  I now suspected that the MB3730A amplifier on the sound board had blown out.  When it goes out, it can take the speaker with it.

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