new life for old Sony Betamax?

[john KB5AG]

Hi, all. My Sony SL-HF500 has been sitting in the shed for 2 years, now my
daughter wants to watch some of the sci-fi stuff I had on tape. It fired
right up, and the tape transport works fine, but the head motor won't turn.
It rotates freely until you press play, then there's obviously a strong
single pole of magnetic force that stops it. So I guess this is a
multi-phase motor and one phase of the driver is dead?

Anyone have a schematic, or can tell me which IC/transistor drives the
motor?

thanks,

John

 

[Jeff]

Try a Google search for "Sony Beta Hall Glue" and read what turns up. Here is
a quick quote from Andy. This fixed the same problem on both of my
SL-HF750's a while back. I carefully removed the glue instead of replacing
them however.

Good Luck,
Jeff

I've seen the hall effect sensors in the motors of sony beta VCRs fail.
I have one that needed new ones in the capstan motor and drum motor. I
think the basic cause was the brown glue they used to secure the sensor
to the board; it turns conductive and corrosive with age. If when you
press play, the capstan motor locks and is very hard to turn by hand,
this is the cause.
--
Andy Cuffe

Hi, all. My Sony SL-HF500 has been sitting in the shed for 2 years, now my
daughter wants to watch some of the sci-fi stuff I had on tape. It fired
right up, and the tape transport works fine, but the head motor won't turn.
It rotates freely until you press play, then there's obviously a strong
single pole of magnetic force that stops it. So I guess this is a
multi-phase motor and one phase of the driver is dead?

Anyone have a schematic, or can tell me which IC/transistor drives the
motor?

thanks,

John

 

[John KB5AG]

Thanks, Jeff! Sounds like exactly the problem I'm having. I'll try your
fix first.

My daughter thanks you!

John


"Jeff" <none@this.time> wrote in message
news:3Rjec.77$hg1.32@nwrddc02.gnilink.net...

Try a Google search for "Sony Beta Hall Glue" and read what turns up. Here
is
a quick quote from Andy. This fixed the same problem on both of my
SL-HF750's a while back. I carefully removed the glue instead of
replacing
them however.

Good Luck,
Jeff

I've seen the hall effect sensors in the motors of sony beta VCRs fail.
I have one that needed new ones in the capstan motor and drum motor. I
think the basic cause was the brown glue they used to secure the sensor
to the board; it turns conductive and corrosive with age. If when you
press play, the capstan motor locks and is very hard to turn by hand,
this is the cause.
--
Andy Cuffe

Hi, all. My Sony SL-HF500 has been sitting in the shed for 2 years, now
my
daughter wants to watch some of the sci-fi stuff I had on tape. It fired
right up, and the tape transport works fine, but the head motor won't
turn.
It rotates freely until you press play, then there's obviously a strong
single pole of magnetic force that stops it. So I guess this is a
multi-phase motor and one phase of the driver is dead?

Anyone have a schematic, or can tell me which IC/transistor drives the
motor?

thanks,

John