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Cassette Deck drive bands
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N_Cook
Jul 7, 2012, 4:16:00 AM7/7/12
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I still regularly replace them for people (tends to be with silicone rubber
bands )
This week something I did not know - found while trying to make sense of
strobing a capstan to set the motor speed. An Aiwa with rotatatable head for
playing the "reverse" side of the tape. Spindle to one capstan was 1.49mm
diameter and the other 1.69mm and proportional size difference to the
capstans, driven by the same band. I'd measured one spindle and then marked
,for strobing, the other capstan. Both decks , Rec/Play & play ,this same
mechanical disparity
bands )
This week something I did not know - found while trying to make sense of
strobing a capstan to set the motor speed. An Aiwa with rotatatable head for
playing the "reverse" side of the tape. Spindle to one capstan was 1.49mm
diameter and the other 1.69mm and proportional size difference to the
capstans, driven by the same band. I'd measured one spindle and then marked
,for strobing, the other capstan. Both decks , Rec/Play & play ,this same
mechanical disparity
N_Cook
Jul 7, 2012, 6:25:37 AM7/7/12
to
Another oddity with this 1992 Aiwa AD WX888 - end of tape sensor. Instead of
a follower that moves with increase of tension in the tape. This uses the
same small holes in the cassette but is a fixed lump of plastic with 3 wires
coming from it, not coils. Capacitively somehow sensing motion or change in
capacitance of ferrite tape to leader transistion ?
a follower that moves with increase of tension in the tape. This uses the
same small holes in the cassette but is a fixed lump of plastic with 3 wires
coming from it, not coils. Capacitively somehow sensing motion or change in
capacitance of ferrite tape to leader transistion ?
Tim Schwartz
Jul 7, 2012, 6:52:13 AM7/7/12
to
Regards,
Tim Schwartz
Bristol electronics
William Sommerwerck
Jul 7, 2012, 7:08:54 AM7/7/12
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> This week something I did not know -- found while
> There is a proportional size difference to the capstans,
> [sic] driven by the same band.
What you mean is that the diameter of the "flange" (or whatever) at the base
of the capstan, which is driven by the same belt, varies so that each
capstan moves the tape at the same linear speed.
If the tape is driven by both capstans at the same time (and I assume it
is), then one capstan is designed to turn ever-so-slightly faster so that
the tape is held under tension.
It's not clear what happens when the tape reverses direction. However, my
Nakamichi used this system, and the tape didn't go spilling into the deck's
innards when it was reversed.
> trying to make sense of strobing a capstan to set
> the motor speed. An Aiwa with rotatatable head for
> playing the "reverse" side of the tape. Spindle to one
> capstan was 1.49mm diameter and the other 1.69mm.
> the motor speed. An Aiwa with rotatatable head for
> playing the "reverse" side of the tape. Spindle to one
> There is a proportional size difference to the capstans,
> [sic] driven by the same band.
What you mean is that the diameter of the "flange" (or whatever) at the base
of the capstan, which is driven by the same belt, varies so that each
capstan moves the tape at the same linear speed.
If the tape is driven by both capstans at the same time (and I assume it
is), then one capstan is designed to turn ever-so-slightly faster so that
the tape is held under tension.
It's not clear what happens when the tape reverses direction. However, my
Nakamichi used this system, and the tape didn't go spilling into the deck's
innards when it was reversed.
William Sommerwerck
Jul 7, 2012, 7:10:16 AM7/7/12
to
I've never heard of ferrite-coated tapes.
N_Cook
Jul 7, 2012, 8:23:16 AM7/7/12
to
William Sommerwerck <grizzle...@comcast.net> wrote in message
news:jt95bg$1vi$1...@dont-email.me...
I wouldn't say it was a slight difference as in the ratio of 1.49 to 1.69
but not such a large difference I had noticed in general handling.
Probably specious accuracy as I did not remove them for good perpendicular
measurement but 44.86mm and 48.79mm of the capstan flanges. Figure-of-S
shape for the band between the flanges, opposite rotational distrection,
only one engaged pinch-wheel at a time of course. .
By ythe way does the USA term for say the Lazy-S ranch mean an S that is
stretched out or "laid on its back" ie turned through 90 degrees? or both ?
news:jt95bg$1vi$1...@dont-email.me...
but not such a large difference I had noticed in general handling.
Probably specious accuracy as I did not remove them for good perpendicular
measurement but 44.86mm and 48.79mm of the capstan flanges. Figure-of-S
shape for the band between the flanges, opposite rotational distrection,
only one engaged pinch-wheel at a time of course. .
By ythe way does the USA term for say the Lazy-S ranch mean an S that is
stretched out or "laid on its back" ie turned through 90 degrees? or both ?
N_Cook
Jul 7, 2012, 8:27:20 AM7/7/12
to
William Sommerwerck <grizzle...@comcast.net> wrote in message
news:jt95e2$29p$1...@dont-email.me...
William Sommerwerck
Jul 7, 2012, 9:20:38 AM7/7/12
to
> I wouldn't say it was a slight difference as in the ratio
> of 1.49 to 1.69 but not such a large difference I had
> noticed in general handling. Probably specious accuracy
> as I did not remove them for good perpendicular
> measurement but 44.86mm and 48.79mm of the capstan
> flanges. Figure-of-S shape for the band between the flanges,
> opposite rotational distrection, only one engaged pinch-wheel
> at a time of course.
Well, that kind of kills my theory. Your original post indicated that this
> of 1.49 to 1.69 but not such a large difference I had
> noticed in general handling. Probably specious accuracy
> as I did not remove them for good perpendicular
> measurement but 44.86mm and 48.79mm of the capstan
> flanges. Figure-of-S shape for the band between the flanges,
> opposite rotational distrection, only one engaged pinch-wheel
> at a time of course.
was a dual-capstan drive. It isn't.
> By the way, does the US term for say the Lazy-S ranch
> mean an S that is stretched out or "laid on its back", ie
> turned through 90 degrees? or both ?
In cowboy parlance, it means "lying on its side". It does not refer to the
shape or aspect ratio.
N_Cook
Jul 7, 2012, 10:15:25 AM7/7/12
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N_Cook <div...@tcp.co.uk> wrote in message
news:jt99tj$nl0$2...@dont-email.me...
Probly diode and photo-resistor, diode on DVM and varying ohmage on another
pair of wires, on varying the ambient light . So would only detect leader
join, not active in the case of a tape jam
news:jt99tj$nl0$2...@dont-email.me...
pair of wires, on varying the ambient light . So would only detect leader
join, not active in the case of a tape jam
N_Cook
Jul 7, 2012, 10:18:28 AM7/7/12
to
William Sommerwerck <grizzle...@comcast.net> wrote in message
news:jt9d2g$7pe$1...@dont-email.me...
Pictoral pub signs like the Red Lion or the King's Head started in Britain
because of total illiteracy amongst a lot of the populace.
hr(bob) hofmann@att.net
Jul 7, 2012, 10:01:17 PM7/7/12
to
On Jul 7, 9:18 am, "N_Cook" <dive...@tcp.co.uk> wrote:
> William Sommerwerck <grizzledgee...@comcast.net> wrote in message
> because of total illiteracy amongst a lot of the populace.- Hide quoted text -
>
> - Show quoted text -
Was that in the 1910's or 1920's <G>.?
> William Sommerwerck <grizzledgee...@comcast.net> wrote in message
>
> - Show quoted text -
Was that in the 1910's or 1920's <G>.?
hr(bob) hofmann@att.net
Jul 7, 2012, 10:00:14 PM7/7/12
to
On Jul 7, 7:23 am, "N_Cook" <dive...@tcp.co.uk> wrote:
> William Sommerwerck <grizzledgee...@comcast.net> wrote in message
> stretched out or "laid on its back" ie turned through 90 degrees? or both ?- Hide quoted text -
> William Sommerwerck <grizzledgee...@comcast.net> wrote in message
>
> - Show quoted text -
usually means rotated to lie on its back
> - Show quoted text -
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