Model STD-4 MARDI GRAS- HUM

Hello-
I have a Model STD-4 MARDI GRAS Jukebox. It's very cool!
In the past week, it's started humming. It does it when it's powered up
and when it's playing a record.
Not sure why it'd start out of the blue, although the volume and tone
were going in and out and up and down a few days before. Now the volume
is relatively low, and the hum is quite apparent.

Does anyone have any ideas or suggestions? Sounds like a grounding
problem, but I'm not sure.

thanks

"barrywomb" wrote in
oups.com:

Hello-
I have a Model STD-4 MARDI GRAS Jukebox. It's very cool!
In the past week, it's started humming. It does it when it's powered up
and when it's playing a record.
Not sure why it'd start out of the blue, although the volume and tone
were going in and out and up and down a few days before. Now the volume
is relatively low, and the hum is quite apparent.

Does anyone have any ideas or suggestions? Sounds like a grounding
problem, but I'm not sure.

thanks



My STD160 had the same problem (mine was a loud hum). I ended up having the
amp rebuilt. It had quite a few bad caps and 2 diodes. My volume was low
on the left channel, gone on the right. Rebuilt the amp, all is good.

How tough is it to rebuild the amp? For mine, all the amp stuff seems
to be in the top portion of the jukebox where all the speaker controls
are. Is that where the amp is or am I totally lost?

On 23 Dec 2004 10:03:51 -0800, "barrywomb"
wrote:

How tough is it to rebuild the amp? For mine, all the amp stuff seems
to be in the top portion of the jukebox where all the speaker controls
are. Is that where the amp is or am I totally lost?

The amp is a chassis at the top of the machine, with three
transformers and a heat sink. All of the electrolytic capacitors
should be replaced.

Cheers,

Tony Miller

ok, that's behind the stuff I was looking at. Is there anywhere to get
a schematic for this STD 4 or do I just look at the values and swap
them?

There should be a complete manual and schematics available as published by
AMR and available from a number of sources. Someone on this group probably
sells them. If you do not come up with a source email me off group and I
will give you some ideas of a place to buy.

From what you are saying there is also a possibility that a driver
transistor has gone out. the symptoms are similar but, it is the right thing
to do to recap the entire amp. If you are not experienced in doing the work
or are willing to accept some losses learning, I suggest that you have a
professional do it. I have done many and it is not for the faint of heaart.
All voltages should be checked in the process to make sure that there are
not any other components that have died or shifted.

Jim

"barrywomb" wrote in message
oups.com...
ok, that's behind the stuff I was looking at. Is there anywhere to get
a schematic for this STD 4 or do I just look at the values and swap
them?

Thanks Jim-
I'm not sure who would do that up here in North Seattle. There used to
be a jukebox place, but it's out of business. Any idea of the cost for
the amp rebuild?


Jim Murphy wrote:
There should be a complete manual and schematics available as
published by
AMR and available from a number of sources. Someone on this group
probably
sells them. If you do not come up with a source email me off group
and I
will give you some ideas of a place to buy.

From what you are saying there is also a possibility that a driver
transistor has gone out. the symptoms are similar but, it is the
right thing
to do to recap the entire amp. If you are not experienced in doing
the work
or are willing to accept some losses learning, I suggest that you
have a
professional do it. I have done many and it is not for the faint of
heaart.
All voltages should be checked in the process to make sure that there
are
not any other components that have died or shifted.

Jim

"barrywomb" wrote in message
oups.com...
ok, that's behind the stuff I was looking at. Is there anywhere to
get
a schematic for this STD 4 or do I just look at the values and swap
them?

You probably are better off to send it to a jukebox amp specialist. If you
need help locating one send me an email off-group. Thansk JIm
"barrywomb" wrote in message
oups.com...
Thanks Jim-
I'm not sure who would do that up here in North Seattle. There used to
be a jukebox place, but it's out of business. Any idea of the cost for
the amp rebuild?


Jim Murphy wrote:
There should be a complete manual and schematics available as
published by
AMR and available from a number of sources. Someone on this group
probably
sells them. If you do not come up with a source email me off group
and I
will give you some ideas of a place to buy.

From what you are saying there is also a possibility that a driver
transistor has gone out. the symptoms are similar but, it is the
right thing
to do to recap the entire amp. If you are not experienced in doing
the work
or are willing to accept some losses learning, I suggest that you
have a
professional do it. I have done many and it is not for the faint of
heaart.
All voltages should be checked in the process to make sure that there
are
not any other components that have died or shifted.

Jim

"barrywomb" wrote in message
oups.com...
ok, that's behind the stuff I was looking at. Is there anywhere to
get
a schematic for this STD 4 or do I just look at the values and swap
them?