Author Topic: '79 Suitcase Randomly Turns Off  (Read 111 times)

Offline Dan

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'79 Suitcase Randomly Turns Off
« on: April 12, 2019, 06:24:53 AM »
Hi, I own a 1979 Mark I Rhodes w/ the Suitcase amp, and the vibrato panel (w/ knobs, and slides for bass and treble).

Recently, I noticed that when I start playing loud, the thing will just shut off, and then occasionally come back to life. The amp makes this popping sound each time it turns back on after this. This seems to be caused by this dim 'mode' that the main red indicator led goes into. It gets dim, and in this mode, it actually blinks to the speed that the vibrato is set to, even when the vibrato is turned off. I notice that if I turn the vibrato too slow, the led will fade out entirely and the whole thing will shut off.\

Anyone know what is causing these random shut offs? I believe something inside the Rhodes is shaking and causing a short. My buddy told me it could be the original 3A fuse near the power input, he said the filament is loose. Could this be true?

Offline pianotuner steveo

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Re: '79 Suitcase Randomly Turns Off
« Reply #1 on: April 13, 2019, 04:01:33 PM »
It sounds like you have poor connnection(s) somewhere in the power section.Intermittently shutting off isn't a short, it is an open circuit. Shorts can burn out parts, blow fuses, trip breakers and in worst cases, cause fires. Open circuits are like turning off a switch. Since it seems to work when it works, this may not be that difficult to fix. What are your soldering skills? Newbie? intermediate? Expert?

It could be bad parts, but always look for the free and easy solutions first, such as bad connections in the power circuit, and bad solder connections. Unplugged, of course.
1960 Wurlitzer model 700 EP
1968 Gibson G101 Combo organ
1975 Rhodes Piano Bass
1979 Wurlitzer 206A EP
1980 Wurlitzer 200A EP
1980 Wurlitzer 270 Butterfly Grand
2000 Yamaha acoustic piano
2004 Hammond XK3
2009 73A Rhodes Mark 7
2009 Korg SV-1 73
....and a few guitars...

Offline pianotuner steveo

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Re: '79 Suitcase Randomly Turns Off
« Reply #2 on: April 14, 2019, 12:37:38 PM »
The first place I would look after unplugging from the wall is starting at the power cord socket then work your way inward. It may be a colder solder joint on a power transistor.
1960 Wurlitzer model 700 EP
1968 Gibson G101 Combo organ
1975 Rhodes Piano Bass
1979 Wurlitzer 206A EP
1980 Wurlitzer 200A EP
1980 Wurlitzer 270 Butterfly Grand
2000 Yamaha acoustic piano
2004 Hammond XK3
2009 73A Rhodes Mark 7
2009 Korg SV-1 73
....and a few guitars...