books about television circuits

M

Mike Ng

Guest
I recently obtained a Mac Classic, which is the ancient 8MHz all-in-one.
Since it's basically useless as a computer, I've been entertaining
thoughts of turning it into a television. I figure I can cheat and use
the tuner from a VCR, and just figure out what lies between composite
out and the CRT.

Now I have a couple television books from my university's library which
discuss everything from the sync generator to the CRT, but they're from
c. 1950 so the diagrams are all tubes. Therefore I'm looking for a book
that uses transistors in its circuit diagrams. (It would be nice to
have a book that uses ICs, but most video ICs I've looked for have been
obsoleted.)

Recommendations? Thoughts? Thanks.
 
Hi Mike,

You could go a step further and look for "one chip television"
solutions. Philips Semi is one option but their web site is, in my
opinion, not very good. Takes patience, lots of it. However, once you
made it through the data sheet those are usually pretty good.

Regards, Joerg

http://www.analogconsultants.com
 
Spehro Pefhany wrote:
On Tue, 19 Oct 2004 10:09:24 -0700, the renowned Mike Ng
ude.yelekreb.scee.yroc@gnm.ROTATE> wrote:


I recently obtained a Mac Classic, which is the ancient 8MHz all-in-one.
Since it's basically useless as a computer, I've been entertaining
thoughts of turning it into a television. I figure I can cheat and use
the tuner from a VCR, and just figure out what lies between composite
out and the CRT.

Now I have a couple television books from my university's library which
discuss everything from the sync generator to the CRT, but they're from
c. 1950 so the diagrams are all tubes. Therefore I'm looking for a book
that uses transistors in its circuit diagrams. (It would be nice to
have a book that uses ICs, but most video ICs I've looked for have been
obsoleted.)

Recommendations? Thoughts? Thanks.


You might be able to find the schematic for an old B&W transistor TV.
Hybrid sets were made for quite a while- I think the horizontal
deflection tube was one of the last to go, especially in big-screen
sets. Perhaps a ca. 1970. small-screen portable. Philco had an all
transistor set as early as 1959 (2" projection).

http://www.tvhistory.tv/1960-Philco-SAFARI-Ad.JPG
I suspect it's electrostatic deflection, though.

The first Sony set is interesting. Only 23 transistors.
http://www.tvhistory.tv/Small-Tiny-Micro%20TV%20Sets.htm


If you can't find them for free online, there may be old Sam's in the
archive at your local reference library or University library or you
can buy copies online for $15 or so.

I don't think you don't want a color TV schematic from that era- they
were very much more complex than the B&W sets.


Best regards,
Spehro Pefhany
Click to expand...
Neat, I didn't realize they had portable TVs back then.

I'll definitely look into this, thanks.
 
I would not be at all surprised if the Mac classic actually generated
composite video internally then used a off the shelf composite monitor.....
Click to expand...
That would be pretty convenient, but the DIY-er in me would rather it
not be so =).

Thanks for your input.
 
Dan Mills (dmills@spamblock.demon.co.uk) writes:
Other thoughts:
I would not be at all surprised if the Mac classic actually generated
composite video internally then used a off the shelf composite monitor.....

The "motherboard" generates the video signal, I don't think it was composite,
Click to expand...
and then there's an "analog" board that is the monitor circuitry. Pull
out "motherboard" and you've got a monitor.

I can't remember, and I'm too lazy to check, what the signal levels are.
It's got to be analog video.

The big problem is that it runs at a higher horizontal frequency; somewhere
around 20KHz, but again I don't remember exactly what.
 
I think you'd learn more applicable knowledge if you plan on using some
discrete IC's, and perhaps a small FPGA or a CPLD for timing generation.
Click to expand...
That's actually the class I'm taking next semester, roughly. We use
Xilinx boards and have a "major design project." I've heard it's the
weeder course for upper division classes.

http://www-inst.eecs.berkeley.edu/~cs150/fa04/OldSites.htm

What I'm aiming to do is plain nutty of course.
 
Building a TV is not just picking out a sync separator chip... that's
relatively easy to do (even with discrete components from scratch). The
hard part is the HV/flyback/deflection/focusing which are all interrelated
in commercial units. It's possible to separate all those functions with
independent circuits but the result may not easily fit in the Mac
Classic case :).
Click to expand...
Hmm, that's true. I just looked at the "Television Receiver" chapter of
my book and those deflection circuits are quite involved. I guess I'll
have to take a look inside sooner or later.
 
Mike Ng wrote:

Building a TV is not just picking out a sync separator chip... that's
relatively easy to do (even with discrete components from scratch). The
hard part is the HV/flyback/deflection/focusing which are all
interrelated
in commercial units. It's possible to separate all those functions with
independent circuits but the result may not easily fit in the Mac
Classic case :).


Hmm, that's true. I just looked at the "Television Receiver" chapter of
my book and those deflection circuits are quite involved. I guess I'll
have to take a look inside sooner or later.
Click to expand...
not to mention all the non-linear magnetics involved. Geyger has a nice
chapter on these in his book nonlinear magnetic control devices.

Cheers
Terry
 
Hi Tim,

The GE Portacolor was still in production up till 78/79, and had not
a single transistor in it. All tubes :). Of course, by some standards
each of those tubes was itself an IC!


Oh man, they probably ran production on that clunker until the last few
Click to expand...
cents of product life had been squished out of the market.

Maybe a smart thing. Yesterday I repaired a coocoo clock. They are still
the same as they were back in grandpa's days.

BTW, one of our old radios has the very first IC ever made. Circa 1925,
multi-function tube with all the resistors and other discretes inside.
No external parts other than an oak box, a variable cap and a honeycomb
coil.

Regards, Joerg

http://www.analogconsultants.com
 
Hi Mike,

That's actually the class I'm taking next semester, roughly. We use
Xilinx boards and have a "major design project." I've heard it's the
weeder course for upper division classes.

http://www-inst.eecs.berkeley.edu/~cs150/fa04/OldSites.htm
Click to expand...
Be happy about it. I wish we would have had those kinds of hands-on
classes in the 70's.

What I'm aiming to do is plain nutty of course.
Click to expand...
Since you live in Silicon Valley I'd use the term "nerdy" instead ;-)

Regards, Joerg

http://www.analogconsultants.com
 
"Terry Given" <my_name@ieee.org> wrote in message
news:I3Add.358$_z2.16165@news.xtra.co.nz...
Mike Ng wrote:

Building a TV is not just picking out a sync separator chip... that's
relatively easy to do (even with discrete components from scratch).
The
hard part is the HV/flyback/deflection/focusing which are all
interrelated
in commercial units. It's possible to separate all those functions
with
independent circuits but the result may not easily fit in the Mac
Classic case :).


Hmm, that's true. I just looked at the "Television Receiver" chapter of
my book and those deflection circuits are quite involved. I guess I'll
have to take a look inside sooner or later.

not to mention all the non-linear magnetics involved. Geyger has a nice
chapter on these in his book nonlinear magnetic control devices.

Cheers
Terry
Click to expand...
Hi,

This is a project I did whilst at college in the late 80's, I had a CRT from
an old colour CGA? monitor and a few other parts and turned it into a TV. As
others have said the deflection parts are hard, for the horizontal
deflection I 'cheated' and used the whole defection/flyback circuit from a
scrap colour TV. Vertical deflection is easier - my college tutor had some
strange ideas about using audio amplifiers for vertical deflection (fond
memories of using the same valves/tubes for both I think) after some failed
push - pull designs I used a conventional vertical output IC TDA3651. Some
capacitor values needed to be adjusted to match the different deflection
coils.

The rest was constructed from off the shelf IC's:

TDA2579A for horizontal oscillator / vertical oscillator and sync
TDA3562 for colour decoder
I used a ready made tuner but struggled to build an IF circuit (on
veroboard!) in the end the whole tuner/IF unit was taken from an old Betamax
video
Power supply was a huge transformer, which needed to be a couple of feet
from the CRT to prevent the picture from 'wobbling' - later a crude and very
unreliable switched mode design was constructed.
Much Later on I added Teletext (SAA5231 SAA5243), remote control (Sony 14"
TV CPU) and Nicam Digital Stereo (Maplin kit)

I then discovered girls and the remains of this project still resides in my
parent's attic!

The above wasn't so much a 'design' but interfacing different building
blocks together to make a TV following manufacturer's data sheets. What
would be really cool in this modern age would be to use a DSP to do all the
analogue work from the IF output of the tuner to the RGB input of the
monitor!

These days TV technology has become more integrated for a basic set with no
digital processing most manufacturer's use one chip for all the low level
signals often this includes the microprocessor. Such chips are not really
hobbyist friendly.

The older parts although obsolete are probably still available from
companies that supply spare parts for TV repair.

If you just want to display TV pictures on the monitor of the MAC the job
will probably be a little easier you will need a colour decoder chip and its
associated circuitry to produce RGB for the monitor and you will need a sync
signal (probably H/V sync) Perhaps start by using the composite output from
a VCR as the 'tuner' and add a proper tuner later.

If your old MAC still works perhaps 'scope the signals going into the
monitor section to give you an idea of the signals you need to create. The
only snag is that the horizontal frequency of the monitor may not match that
of TV , if its only a bit higher it might still lock or be adjustable - if
its way out (standard VGA is double) more drastic modifications will be
required to the existing monitor.

Hope my musings help

Philip
 
Hi Mike,

I guess my goal in this project is to be as low level as possible.
I'm a EE student at college, and I'd like put as much practical
theoretical knowledge into this as possible. I think it's something
that's missing from my curriculum, as my next classes concentrate on
designing integrated circuits. I want to do something with discretes,
no matter how sprawling and inelegant it may be.
Click to expand...
Then maybe it is best to obtain a schematic from a late 70's TV set
where they used transistors but not a lot of chips except for regular
opamps. But I'd scavenge the tuner from an old set, these are difficult
to build.

Regards, Joerg

http://www.analogconsultants.com
 
Mike Ng wrote:

I recently obtained a Mac Classic, which is the ancient 8MHz all-in-one.
Since it's basically useless as a computer, I've been entertaining
thoughts of turning it into a television. I figure I can cheat and use
the tuner from a VCR, and just figure out what lies between composite
out and the CRT.

Now I have a couple television books from my university's library which
discuss everything from the sync generator to the CRT, but they're from
c. 1950 so the diagrams are all tubes. Therefore I'm looking for a book
that uses transistors in its circuit diagrams. (It would be nice to
have a book that uses ICs, but most video ICs I've looked for have been
obsoleted.)
Click to expand...
I used to have (But cannot now find to check the ISBN) a book called "Colour
television theory" which in spite of its name actually had lots of
fragments of circuitry and comments on how the things worked. It really was
not excessively theoretical. Based around PAL sets of circa early 80s
vintage but it might be useful.


Other thoughts:
I would not be at all surprised if the Mac classic actually generated
composite video internally then used a off the shelf composite monitor.....


Regards, Dan.
 
On Tue, 19 Oct 2004 10:09:24 -0700, the renowned Mike Ng
<ude.yelekreb.scee.yroc@gnm.ROTATE> wrote:

I recently obtained a Mac Classic, which is the ancient 8MHz all-in-one.
Since it's basically useless as a computer, I've been entertaining
thoughts of turning it into a television. I figure I can cheat and use
the tuner from a VCR, and just figure out what lies between composite
out and the CRT.

Now I have a couple television books from my university's library which
discuss everything from the sync generator to the CRT, but they're from
c. 1950 so the diagrams are all tubes. Therefore I'm looking for a book
that uses transistors in its circuit diagrams. (It would be nice to
have a book that uses ICs, but most video ICs I've looked for have been
obsoleted.)

Recommendations? Thoughts? Thanks.
Click to expand...
You might be able to find the schematic for an old B&W transistor TV.
Hybrid sets were made for quite a while- I think the horizontal
deflection tube was one of the last to go, especially in big-screen
sets. Perhaps a ca. 1970. small-screen portable. Philco had an all
transistor set as early as 1959 (2" projection).

http://www.tvhistory.tv/1960-Philco-SAFARI-Ad.JPG
I suspect it's electrostatic deflection, though.

The first Sony set is interesting. Only 23 transistors.
http://www.tvhistory.tv/Small-Tiny-Micro%20TV%20Sets.htm


If you can't find them for free online, there may be old Sam's in the
archive at your local reference library or University library or you
can buy copies online for $15 or so.

I don't think you don't want a color TV schematic from that era- they
were very much more complex than the B&W sets.


Best regards,
Spehro Pefhany
--
"it's the network..." "The Journey is the reward"
speff@interlog.com Info for manufacturers: http://www.trexon.com
Embedded software/hardware/analog Info for designers: http://www.speff.com
 
Hi Rich,

Thanks, I didn't know player pianos used to work with a vacuum system.

The other thing I restored a while ago was a Hammond organ. The amp is
electronic, with tubes. But the tone generator is a different matter. A
motor drives a long chain of gears. Dozens upon dozens of disks rotate
along adjustable pickup coils at different speeds. These generate the
tones. It is a marvel of mechanical engineering and as far as I read
about it there still isn't a synthesizer that can mimick this sound
100%. At least that's what many musicians say. Oh, and the motor won't
start on its own. Instead of a cap there is yet another "start motor"
which gets engaged by holding a start switch for a few seconds.

One of my fantasy projects is to do a player piano from an ordinary
piano and pinball machine solenoids.


It might be hard to obtain 88 of these. Maybe you can get your hands on
Click to expand...
a cheap surplus stash of doorbell solenoids. These have long travel and
are often pretty quiet. I don't know about their number of strokes
before end of life though. The challenge will be the mechanical link. In
our old piano they used leather for such linkages in the mechanism. Only
very few types of leather work, I was told when restoring that one.

Regards, Joerg

http://www.analogconsultants.com
 
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