Driver to drive?

[mixed nuts]

On 3/7/2016 9:24 PM, DaveC wrote:

I've always been told only use silicone grease on electricals, others get
corrosive when electricity is applied.
NT

I (op) in my research came across this warning (which, of course I cannot
find now): silicone grease in the presence of plasma (ie, arcing switch
contacts and such) turns to silicon dioxide, an abrasive.

Yup. Quartz is abrasive and the oil can be polymerized and form a
tenacious insulating coating. A number of mil specs prohibit silicones
in electrical equipment for those reasons.

--
Grizzly H.

 

[Phil Allison]

DaveC wrote:

Oh, smarter-than-I people,

** That pretty much includes the entire human race.

http://imgur.com/WPEoOu1

The 2 belt-drive capstan flywheels in an auto-reverse cassette mechanism are
different sizes. (Motor drive pulley will be in the small loop end of the
belt in illustration above.)

How does that result in the same tape speed in both directions?

** The capstans have compensating diameters - or the motor changes speed when the tape reverses.

Using non identical flywheels avoids a possible resonance problem in the system.


> Confused...

** You are.

.... Phil

 

[Lasse Langwadt Christense]

Den fredag den 11. marts 2016 kl. 22.22.16 UTC+1 skrev DaveC:

Oh, smarter-than-I people,

http://imgur.com/WPEoOu1

The 2 belt-drive capstan flywheels in an auto-reverse cassette mechanism are
different sizes. (Motor drive pulley will be in the small loop end of the
belt in illustration above.)

How does that result in the same tape speed in both directions?

Confused...

https://youtu.be/2CE_zmpHcWQ

 

[Martin Riddle]

On Fri, 11 Mar 2016 16:39:45 -0800 (PST), Lasse Langwadt Christensen
<langwadt@fonz.dk> wrote:

Den fredag den 11. marts 2016 kl. 22.22.16 UTC+1 skrev DaveC:
Oh, smarter-than-I people,

http://imgur.com/WPEoOu1

The 2 belt-drive capstan flywheels in an auto-reverse cassette mechanism are
different sizes. (Motor drive pulley will be in the small loop end of the
belt in illustration above.)

How does that result in the same tape speed in both directions?

Confused...

https://youtu.be/2CE_zmpHcWQ

Cool, I got a CS-34D.
It made some good recordings with tdk SA tapes.


Cheers

 

I thought I already posted this butm these guys are all nuts.

That is NOT a dual capstan deck, it has two capstans to facilitate reverse play. they are not both active at the same time, How could they be ? They can't. Unless you stick that pinch roller inside the cassette and... fukit, they tried that with eight tracks. Plus it wouldn't fit.

Only one capstan is active at a time, that is when the pinch roller is engaged. both capstans turn in opposite directions all the time but it doesn't mean shit until the pinch roller hits the tape. If both ever hit at the same time the deck would come to a screeching halt, LITERALLY.

Look at it more closely and you will see.

 

Oh, and what got lost here was I posted that the thickness of the capstan belt makes the difference in diameter necessary. Some decks may have separate speed setting for each direction but in 40 years I have never run into one.

 

[DaveC]

jurb6006@gmail.com wrote:

Oh, and what got lost here was I posted that the thickness of the capstan
belt makes the difference in diameter necessary.

Does that makes the replacement belt manufacture critical? Didn’t know this
when I ordered belts (yet to arrive). Just treated selection like a car’s
fan belt: primarily, original circumference; second, width; tertiary (or not
at all), thickness. Will have to see what I get...

This deck does have pitch control on the front panel so can adjust for that,
if excessive, but only 1 speed adjust pot, not separate ones for fwd, rev.

(op)

 

[legg]

On Sat, 12 Mar 2016 08:39:28 -0800, DaveC <not@home.cow> wrote:

jurb6006@gmail.com wrote:

Oh, and what got lost here was I posted that the thickness of the capstan
belt makes the difference in diameter necessary.

Does that makes the replacement belt manufacture critical? Didn’t know this
when I ordered belts (yet to arrive). Just treated selection like a car’s
fan belt: primarily, original circumference; second, width; tertiary (or not
at all), thickness. Will have to see what I get...

This deck does have pitch control on the front panel so can adjust for that,
if excessive, but only 1 speed adjust pot, not separate ones for fwd, rev.

(op)
What model number?

RL

 

[DaveC]

What model number?

RL

Sony TC-WR99ES.

I’ve got original svc man and similar models (using same mechanism) sm’s
also.

Thanks.

 

On Saturday, 12 March 2016 20:19:32 UTC, John Larkin wrote:

All those mechanical means of reproducing sound - wax disks, tinfoil,
shellac, plastic, wire, tape - were all awful. Chemical photography
was a nuisance, too. Ditto typing and carbon paper.

If your source material is on tape, it's on tape, end of story.

I don't buy the inside vs outside of belt thing.


NT

 

[Phil Allison]

DaveC wrote:

What model number?

RL

Sony TC-WR99ES.

** See:

http://bilder.hifi-forum.de/max/352931/sony-tc-wr99es-tapedeck-innenleben_171536.jpg

The heads are all 4 track - correct ?

So no head spinning needed.

..... Phil

 

[Phil Allison]

tabb...@gmail.com wrote:

I don't buy the inside vs outside of belt thing.

** I agree.

Where the drive belt is curved, the outside radius is greater - but both flywheels are on the INSIDE of curves.


..... Phil

 

[Phil Allison]

John Larkin wrote:

All those mechanical means of reproducing sound - wax disks, tinfoil,
shellac, plastic, wire, tape - were all awful.

** There was one genuinely hi-fi, analogue tape recorder available to the public. The Hi-Fi VCR, which came in Beta and VHS versions.

Recordings were made with a pair of FM carriers in the MHz range. S/n ratio approached 90dB while all the other shortcomings of tape were rendered negligible. Up to 6 hours recording on one cassette too.

Some studios used them as master recorders cos they outperformed R-R machines by such a large margin.

Odd how they never caught on in this role.


... Phil

 

[Cydrome Leader]

Phil Allison <pallison49@gmail.com> wrote:

John Larkin wrote:



All those mechanical means of reproducing sound - wax disks, tinfoil,
shellac, plastic, wire, tape - were all awful.


** There was one genuinely hi-fi, analogue tape recorder available to the public. The Hi-Fi VCR, which came in Beta and VHS versions.

Recordings were made with a pair of FM carriers in the MHz range. S/n ratio approached 90dB while all the other shortcomings of tape were rendered negligible. Up to 6 hours recording on one cassette too.

Some studios used them as master recorders cos they outperformed R-R machines by such a large margin.

Odd how they never caught on in this role.

I was taught the same thing about the HiFi VCRs. Never did any testing
with it though. Reel to reel units were more fun to play with.

 

[DaveC]

Sony TC-WR99ES.

** See:

http://bilder.hifi-forum.de/max/352931/sony-tc-wr99es-tapedeck-
innenleben_1715

36.jpg

The heads are all 4 track - correct ?

So no head spinning needed.
.... Phil

2-track heads, spinning for autoreverse.

If I recall (it’s been a few decades...) Sony didn’t make a dual mech
machine with 4-track head. It was available in single mech only. My priority
at the time was doing extended recordings (record on mech A, automatically
continue on mech B) so dual it was.

 

"
Some studios used them as master recorders cos they outperformed R-R >machines by such a large margin."

And others did not because of their limitations. A buzz is nice when sitting around with your olady listening to some shit. It is not so nice when you are trying to make a master recording.

All AFM hifi recording techniques sufferred from the buzz. they got rid of it with DBX but if you got ears you can still hear it. Noise reduction does ot get rid of the noise - it just asks it or puts up the sound to mask it. Then compensates on playback.

I have had both beta and VHS hifi decks, many of them in fact. I have had them both brand new out of the box. I also had some connections to the manufacturer (Sony) and the bottom line was, if I didn't like the audio performence they would refund my money. There was NOTHING they could do about the buzz.

This would be at 60 Hz or at 50 Hz across the pond. There simply was no way to splice the AFM back together after the head switching. the people who designed the depth multiplexing bullshit and put the extra heads on the VHS decks because they didn't have the bandwidth didn't get much farther either.. What's more, their idea made the picture quality worse. In beta hifi, the modifications actually made the picture quality better.VHS had to catch up.. And still beta was the better format.

 

[Les Cargill]

Phil Allison wrote:

John Larkin wrote:



All those mechanical means of reproducing sound - wax disks,
tinfoil, shellac, plastic, wire, tape - were all awful.


** There was one genuinely hi-fi, analogue tape recorder available to
the public. The Hi-Fi VCR, which came in Beta and VHS versions.

Recordings were made with a pair of FM carriers in the MHz range. S/n
ratio approached 90dB while all the other shortcomings of tape were
rendered negligible. Up to 6 hours recording on one cassette too.

Some studios used them as master recorders cos they outperformed R-R
machines by such a large margin.

Odd how they never caught on in this role.


... Phil

I used one as a mixdown recorder. Painful - the transport was dog
slow to change states. You fast-forwarded and rewound at your peril (
although keeping notes on the index counter minimized that ).

The one I had also had an AGC you could not defeat. Some did,
some didn't.

They also require some sort of valid video signal when recording.

--
Les Cargill

 

[Rob]

Les Cargill <lcargill99@comcast.com> wrote:

I used one as a mixdown recorder. Painful - the transport was dog
slow to change states. You fast-forwarded and rewound at your peril (
although keeping notes on the index counter minimized that ).

The one I had also had an AGC you could not defeat. Some did,
some didn't.

They also require some sort of valid video signal when recording.

No! The old VHS HiFi recorder I had years ago actually had a separate
audio-only recording mode where it could generate everything it required
itself (I think some dummy sync was generated) and the signal levels
were somehow altered so the margins for dropouts were higher.

Still it was only useful to make recordings of concerts and play them
back entirely, not to skip back and forth all the time.

 

On 13 Mar 2016 09:07:21 GMT, Rob <nomail@example.com> wrote:

Les Cargill <lcargill99@comcast.com> wrote:
I used one as a mixdown recorder. Painful - the transport was dog
slow to change states. You fast-forwarded and rewound at your peril (
although keeping notes on the index counter minimized that ).

The one I had also had an AGC you could not defeat. Some did,
some didn't.

They also require some sort of valid video signal when recording.

No! The old VHS HiFi recorder I had years ago actually had a separate
audio-only recording mode where it could generate everything it required
itself (I think some dummy sync was generated) and the signal levels
were somehow altered so the margins for dropouts were higher.

Still it was only useful to make recordings of concerts and play them
back entirely, not to skip back and forth all the time.

I had the JVC 725 which could record Hi-Fi FM audio only at half speed
for 8 hours on a 4 h VHS cassette. You could overwrite the
longitudinal track with 8 h Lo-Fi recording, so you could have 16 h of
audio on a 4 h cassette.

It was also a nice monitor recorder (required by the law) to record
the transmission from a radio stallion (FM to the right, AM
transmitter to the left channel) for 8 hours and due to the simple
mechanical handling, even the station currently active DJ could change
the cassette every 8 hours, instead of requiring some open reel tape
changes.

 

[Les Cargill]

Rob wrote:

Les Cargill <lcargill99@comcast.com> wrote:
I used one as a mixdown recorder. Painful - the transport was dog
slow to change states. You fast-forwarded and rewound at your peril (
although keeping notes on the index counter minimized that ).

The one I had also had an AGC you could not defeat. Some did,
some didn't.

They also require some sort of valid video signal when recording.

No! The old VHS HiFi recorder I had years ago actually had a separate
audio-only recording mode where it could generate everything it required
itself (I think some dummy sync was generated)

Most likely. It's kind of interesting that they thought about that.

and the signal levels
were somehow altered so the margins for dropouts were higher.

Still it was only useful to make recordings of concerts and play them
back entirely, not to skip back and forth all the time.

--
Les Cargill