This unit keeps blowing fuses. I'm starting a troubleshooting sequence, first step, I measure the primary resistance. I'm getting 1.4 ohm. From what I've read, anything lower than 2 ohm is questionable. Is this the cause of my overcurrent situation? I'm measuring 4 ohm on some of my other Marantzs...
If you are measuring with a typical DVM, then readings ubder a few ohms are far from accurate.
Otherwise, no idea sorry. I have a 2285B but mine has always worked fine.
Otherwise, no idea sorry. I have a 2285B but mine has always worked fine.
Disconnect the secondary windings from the circuit and power on with a light bulb in series with the live/hot wire. Make sure the secondaries arent touching anything (isolate them with tape). If the bulb lights, the transformers dead.
Now I know why its nice to have the schematic... I followed the power to the output section and Marantz was good enough to provide a simple way to unplug the power to it. I pulled them both off and now the unit appears to power up, the filter caps charge and have voltage on them 52, -52 and I can hear the speaker relay click. There are two sets of two 2SD427 and 2SB557 per side and they are wire wrapped to terminals conveniently located for testing. These are original Marantz, will they be hard to find? Will I need to change them all (one set of 4 or the other)? Any chance some other fault is causing them to blow or do these just go out every once in a while?
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