Marantz 2230 restoring it from scratch

Update: plugged into dbt and tested voltage with switch on and I'm only getting 65V to the receiver. Is that normal with a dbt?

Also, I plugged straight into wall and receiver got 121V. Powered it on, nothing...No voltage to J808. Nor the main Caps. Only place I see voltage is on the prongs of the rear switched inputs and the fuse.
the yellow wires that leave the transformer to the back of the P800 board have no voltage.
 
Are you sure you are getting voltage out of the switch to the transformer? If you are, it's likely the transformer like you said. But switches go bad more often than transformers.
 
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The picture is were I tested with a MM. red for positive, white for negative. I got nothing from P800, main CAP.
.mbottom.jpg
 
The question still seems unanswered whether power is getting past the power switch. I would remove the front plate and (with unit unplugged) drop the switch down out of the chassis. Then check for continuity between the hot terminals and switched terminals. There should be no continuity when button is out and continuity when it is in. When everything is dead, first thing is to check the fuse and second is to ensure the switch is working.
 
The unswitched outlet in the back should have ~120 volts "AC" regardless of the switch condition or position.

Remember were reading a.c. voltage on the primary side. You should also have ~120 from your dim bulb tester.

If these conditions aren't met, there's no point in checking anything else. 61vac isn't even enough to close the relay.

If you're powering this on at all it needs to be through a proper working DBT and for no longer than it takes to get a stable reading assuming your leads are hooked up to the test points before applying power. Once you get a stable reading immediately power off or you are causing far more damage to the unit.

Leave the unit off. Let's test your DBT. A 60-100 watt bulb works fine. Plug it in and plug your leads into the outlet. With the meter set to read a range of 120VAC, turn it on. Are you getting 117-125 volts?

The light bulb is in circuit to limit current, not voltage and to alert you by glowing brightly If something inside the unit is drawing excess current which is what is making more current through the bulb making it get brighter. AFTER letting it sit for a while, then plugging in through the dbt and turning in, it should glow brightly right away and fade out. This is current filling the main filter capacitors which only takes a second or two. It usually helps to dim the lights and shut the blinds while doing this so you can see this process better.

So, 120 or so from the DBT without the Marantz plugged in?

If yes, pull the output transistors and test them outside of the unit. It's only 2 screws each. Do one at a time so you don't mix them up.

Here's a link to how to test them properly.
http://audiokarma.org/forums/index.php?threads/bipolar-junction-transistor-testing-basics.43186/

Do this before applying any more power to the unit.
 
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with the power switch out I tested leads pressed out, no continuity. Pressed in continuity at 00.2 rock solid connection.
 
The unswitched outlet in the back should have ~120 volts "AC" regardless of the switch condition or position.

Remember were reading a.c. voltage on the primary side. You should also have ~120 from your dim bulb tester.

If these conditions aren't met, there's no point in checking anything else. 61vac isn't even enough to close the relay.

If you're powering this on at all it needs to be through a proper working DBT and for no longer than it takes to get a stable reading assuming your leads are hooked up to the test points before applying power. Once you get a stable reading immediately power off or you are causing far more damage to the unit.

Leave the unit off. Let's test your DBT. A 60-100 watt bulb works fine. Plug it in and plug your leads into the outlet. With the meter set to read a range of 120VAC, turn it on. Are you getting 117-125 volts?

The light bulb is in circuit to limit current, not voltage and to alert you by glowing brightly If something inside the unit is drawing excess current which is what is making more current through the bulb making it get brighter. AFTER letting it sit for a while, then plugging in through the dbt and turning in, it should glow brightly right away and fade out. This is current filling the main filter capacitors which only takes a second or two. It usually helps to dim the lights and shut the blinds while doing this so you can see this process better.

So, 120 or so from the DBT without the Marantz plugged in?

If yes, pull the output transistors and test them outside of the unit. It's only 2 screws each. Do one at a time so you don't mix them up.

Here's a link to how to test them properly.
http://audiokarma.org/forums/index.php?threads/bipolar-junction-transistor-testing-basics.43186/

Do this before applying any more power to the unit.

My DBT is only getting 55v when the leads of the MM are into the sockets.
 
Revisit the DBT wiring. This is a very important part of the diagnosis procedure.

For 2 wire.
images.png

3 wire
DBT_Sch.jpg
 
Thanks for the excellent diagrams. I'll verify it's correctly wired tonight.


I would use a different switch without that light. You won't need it and it may have something to do with why it's not working properly. You'll get confirmation from the bulb when it flows electrons.

Remember the DBT is going to be needed for after we get those shorted components replaced. We have already confirmed something is shorted by the constant fuse blowing. Thank goodness for fuses!

My bets are one of more of the outputs. Definately pull these and test them before trying to plug into anything. I know it's redundant but I'll always test them for continuity before using the diode function. It's quick and easy way to spot shorted components. Literally takes 5 seconds to test across b2e, b2c and c2e and most meters usually respond with a beep to let you know it's bad. If they pass that test, odds are they aren't your source of current draw.
 
The DBT, hard to see, but looks like you are only feeding one leg of the 120 thru the outlet. Not wired correctly.
 
okay, rewired the dbt....lit up like a Christmas tree...so I have a major short.
The main change I made since getting this is the power cord and the power board.

Can someone confirm the wire colors going to the unswitched terminals where the power cord is soldered to?

Here is a close up of the back of the power board. See any issues?IMG_20170323_220111.jpg
 
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