Boss BR-1180 No Power on

[ca7922303]

No power on, anyone have any experience with these?

[DrGonz78]

I did just take one of those apart to clean it up for my nephew. The main issues are with the hard drive failing and it's useless at that point. I changed the drive on it at one point and it fixed it again. All the little momentary buttons are typical dirty and may not work at all. But when you say "power on" I assume we are talking the light on the house coming on. In that case make sure it's the correct power supply.

Edit: Oh those units sound horrible when recording and monitoring. I don't think they are properly shielded and you really have to find a good place to keep the buzz down.

[ca7922303]

I did just take one of those apart to clean it up for my nephew. The main issues are with the hard drive failing and it's useless at that point. I changed the drive on it at one point and it fixed it again. All the little momentary buttons are typical dirty and may not work at all. But when you say "power on" I assume we are talking the light on the house coming on. In that case make sure it's the correct power supply.

Edit: Oh those units sound horrible when recording and monitoring. I don't think they are properly shielded and you really have to find a good place to keep the buzz down.

That's correct, light not coming on, I'm getting 12vdc I believe I remember that when I checked the power supply. Haven't opened unit up yet. Plugged the adapter into wall and used DMM on other end of adapter cord.

[sugeda]

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[ca7922303]

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Appreciate it.

[DrGonz78]

Thanks again Sugeda!! Personally I would start at the most simple approach. Clean. I would start by cleaning the momentary on/off switch. Wouldn’t it be funny if that was all it was to get it to turn on. With schematic it sure helps going further ahead.

[ca7922303]

Thanks again Sugeda!! Personally I would start at the most simple approach. Clean. I would start by cleaning the momentary on/off switch. Wouldn’t it be funny if that was all it was to get it to turn on. With schematic it sure helps going further ahead.

Sprayed contact cleaner on power switch with unit not opened up yet and get a flicker of the screen and lights on the two(2) sens on mic phantom input.

[ca7922303]

Photos of power switch. This boss unit is a 2004 made in Japan.

[g1]

Power switch is momentary, so if you see any action at all when you press it (display flicker), it's probably ok.

Pg.26 of manual pdf shows some things that should be running whenever the power supply is connected, even when unit is turned off. Check the following:
IC48, 78M09 regulator, 9V at pin3.
IC22, M62270GP converter, 3.3V at pin1, also 3.3V at D55 cathode.
IC49, 29M33 regulator, 3.3V at pin3.

[ca7922303]

Power switch is momentary, so if you see any action at all when you press it (display flicker), it's probably ok.

Pg.26 of manual pdf shows some things that should be running whenever the power supply is connected, even when unit is turned off. Check the following:
IC48, 78M09 regulator, 9V at pin3.
IC22, M62270GP converter, 3.3V at pin1, also 3.3V at D55 cathode.
IC49, 29M33 regulator, 3.3V at pin3.

IC48 pin3(9V)
IC22 pin1(3.3V)
D55 cathode (3.3V)
IC49 pin3(3.3V)

[g1]

Check DC volts at Q31A, pins 7/8. Then press power button and re-check.

[ca7922303]

Q31 pin7(0.0mv)
Q31 pin8(0.0mv)
Pin 7/8 goes to about (2V) with power button pushed then runs slowly back down to (0.0mv).

[g1]

Pin 7/8 goes to about (2V) with power button pushed then runs slowly back down to (0.0mv).

Now do the same test at Q31A pin2, and Q33 pin1.

[ca7922303]

Now do the same test at Q31A pin2, and Q33 pin1.

Q31 pin2(9v)
Q31 pin2 pushing power switch blinks to (6v)then back to (9V)
Q33 pin1 does the same as Q31 pin2, blinks (6v), then back to (9v).

[g1]

Q33 pin1 does the same as Q31 pin2, blinks (6v), then back to (9v).

I think you are checking pin3, we need to know pin1.