Toshiba SDV398 VHS/DVD combo with built in tuner.

Everything works but occasionally it stops recording about 15 minutes short
of programmed time. The clock keeps the correct time and the tape is new.

--
Boris

Boris Mohar wrote in message
...

Toshiba SDV398 VHS/DVD combo with built in tuner.

Everything works but occasionally it stops recording about 15 minutes
short
of programmed time. The clock keeps the correct time and the tape is new.

--
Boris


with a stop watch , check it is exactly 15 minutes to the second or just
plus or minus 5 minutes say, for 1 , 2 and 3 hour records , also try with 3
hour and 4 hour tapes to see if there is a difference

"Boris Mohar" wrote in message
...

Toshiba SDV398 VHS/DVD combo with built in tuner.

Everything works but occasionally it stops recording about 15 minutes
short
of programmed time. The clock keeps the correct time and the tape is new.

--
Boris


What happens if you play a tape back for the same length of time ? Could be
a simple mechanical problem like a poor take-up drive that struggles to keep
the take-up reel turning when a certain weight of tape has been wound on. If
the take-up reel stops turning, the mechanism control micro will stop the
machine.

Arfa

Arfa Daily wrote in message
...


"Boris Mohar" wrote in message
...

Toshiba SDV398 VHS/DVD combo with built in tuner.

Everything works but occasionally it stops recording about 15 minutes
short
of programmed time. The clock keeps the correct time and the tape is
new.

--
Boris


What happens if you play a tape back for the same length of time ? Could
be
a simple mechanical problem like a poor take-up drive that struggles to
keep
the take-up reel turning when a certain weight of tape has been wound on.
If
the take-up reel stops turning, the mechanism control micro will stop the
machine.

Arfa


the most likely reason.
Either loss of friction in a slip clutch or wear in a pivot allowing a
pulley in the jockey wheel assembly to touch the chassis, both situations
when sufficient diameter of tape has built onto the take-up spool to trigger
the loss of drive

On Sun, 6 Jan 2013 16:39:51 -0000, "Arfa Daily"
wrote:



"Boris Mohar" wrote in message
.. .

Toshiba SDV398 VHS/DVD combo with built in tuner.

Everything works but occasionally it stops recording about 15 minutes
short
of programmed time. The clock keeps the correct time and the tape is new.

--
Boris


What happens if you play a tape back for the same length of time ? Could be
a simple mechanical problem like a poor take-up drive that struggles to keep
the take-up reel turning when a certain weight of tape has been wound on. If
the take-up reel stops turning, the mechanism control micro will stop the
machine.

Arfa

It never fails on playback. Could there be some subtle transport load
difference between record and playback?



Regards,

Boris Mohar

Got Knock? - see:
Viatrack Printed Circuit Designs (among other things) http://www.viatrack.ca

void _-void-_ in the obvious place

Everything works but occasionally it stops recording about
15 minutes short of programmed time. The clock keeps the
correct time and the tape is new.
It never fails on playback.

My first VCR, circa 1981, had a timer problem connected with an incorrectly
designed chip. If you set it to (say) start recording at 11:30PM and stop at
1:00AM, it would often quit at midnight.

"Boris Mohar" wrote in message
...
On Sun, 6 Jan 2013 16:39:51 -0000, "Arfa Daily"
wrote:



"Boris Mohar" wrote in message
. ..

Toshiba SDV398 VHS/DVD combo with built in tuner.

Everything works but occasionally it stops recording about 15 minutes
short
of programmed time. The clock keeps the correct time and the tape is
new.

--
Boris


What happens if you play a tape back for the same length of time ? Could
be
a simple mechanical problem like a poor take-up drive that struggles to
keep
the take-up reel turning when a certain weight of tape has been wound on.
If
the take-up reel stops turning, the mechanism control micro will stop the
machine.

Arfa

It never fails on playback. Could there be some subtle transport load
difference between record and playback?



Unlikely. Can't think of any reason for there to be any difference, and
can't say that I've ever seen any make or model that does have any
difference. Have you ever actually seen exactly what it does when it quits,
or has it always been just something that you've discovered when you come to
play back the tape ? Is there any consistency to it, or is it just random ?
To be honest, it's beginning to sound like one of those problems that you
just never get to the bottom of. Time to retire it in favour of a more
'modern' solution such as a PVR maybe ?

Arfa

William Sommerwerck wrote in message
...
Everything works but occasionally it stops recording about
15 minutes short of programmed time. The clock keeps the
correct time and the tape is new.
It never fails on playback.

My first VCR, circa 1981, had a timer problem connected with an
incorrectly
designed chip. If you set it to (say) start recording at 11:30PM and stop
at
1:00AM, it would often quit at midnight.


So a divide by zero / year 2000 type problem with that one. I would have set
the clock 12 hours out on that one, assuming only recording over midnight
and never noon
Perhaps the OP should take a careful note of times , assuming there is a
timecode recorded , then see if there is a consistency in the drop out times
at recording.

I just looked through my repair tips , maybe relevant

Ferguson FV21
Manual record and short lead-time timed record OK but failure
of overnight record.
Replaced the the 3 small electrolytics on the clock / timer panel
and broke / inspected /remade all connections and
also at someone's suggestion tightened all earthing point through-pcb
screws on the various boards.Somewhere along the line must have
effected a cure.