TV and Video related projects
This page contains information about TV and video related projects.
VHF/UHF spectrum analyser
Computer based TV test pattern generator
IVS monitor power supply
VHF/UHF spectrum analyzer
This is a simple spectrum analyzer based on a TV tuner. Below is a
of the setup:
The tuner unit and IF amplifier/filter is at the top left, the module
to the right is the sweep signal generator which generates the 0-33V
voltage which tunes the tuner. The power supply is at the bottom. Below
is a photo of the output of the spectrum analyzer on an oscilloscope
an aerial signal:
I did not use any IF-filtering in this design, the bandwidth is the
bandwidth of the tuner output. Neither did I use a peak detector, the
on the scope is the actual IF signal. Furthermore as no signal
is done on the output, the amplitude is expressed linearly on the scope
and not logarithmically.
I am currently busy to build the above spectrum analyzer into a case.
Below are a picture of the spectrum analyzer.
Currently only the sweep generator and IF output directly from the
is working. I have yet to design the IF filtering, peak detector and
to logarithmic amplifier.
The three vertical gray wheels are used to control the tuning frequency
and/or the sweep range. There are two tuning sources, the fixed source,
as well as the sweep generator. The switch below the gray knobs selects
which source is used for tuning. The two LEDs above the switch forms
of a window comparator which compares the tuning voltage of the sweep
to the fixed tuning voltage.
The yellow knob adjusts the gain of the tuner. Currently it is not
The UHF/VHF slide switch selects the frequency band. The LOG/LIN switch
selects the type of amplifier. The WIDE/NARROW switch selects the IF
The MARKER switch puts a marker into the SCOPEY output which
when the sweep generator frequency equals the fixed frequency. This
is derived from the window comparator driving the LEDs.
Computer based TV test pattern generator
I have modified a Aquarius home computer to be used as a TV test
generator. Below is a picture of the setup.
I have basically build the cassette recorder, power supply and computer
into one box. I have also added a composite video output. The Aquarius
only had a RF output. The signal level of the composite output is
from 0Vpp to about 2Vpp. I have written a simple program to generate
test patterns. Below is the main screen when the program is run:
Here I can select which pattern I would like to generate. The red,
blue and white screens are mainly used for purity adjustments. Below is
the color bar test pattern. The colorbar pattern is mainly used for
Below is the crosshatch pattern. The crosshatch pattern is used to
adjust the convergence of a TV.
Using a home computer as a test pattern generator have several
One being the process of loading the program from tape. The other
is the fact that the area used for graphics output is smaller than the
TV screen. The cyan border around the above images cannot be used for
output. This is a problem with especially the crosshatch pattern, since
one cannot see how the convergence operates on the edges of the screen.
I am currently in the process of designing a microprocessor based test
pattern generator. It will possibly be based on a PIC16F84 since I have
already used that device to generate a colorbar test pattern. I will
be using the AD724 composite encoder chip to generate the composite
I have recently build a new cover for the Aquarius based test pattern
generation using 0.6mm galvanised sheet steel. Below is a top view with
the cover removed:
The tape recorder and its power supply is to the left. The Aquarius
motherboard is at the bottom right of the tape recorder. The Aquarius
power supply is above the Aquarius motherboard on the left. The module
in the expansion slot of the Aquarius is additional memory. Just above
the memory module is the BNC video output as well as the RF output. The
board left of the outputs is the video amplifier. Below is the test
pattern generator from the front and from the back.
I have build this power supply unit for testing LCD monitors that are
used with IVS on film cameras. It can supply power to two monitors. It
has a voltage as well as a current meter, as well as several different
output voltages. It also contains a video distribution amplifier. Below
is a front view of the unit:
The left LCD display indicates the current output voltage to the
monitor. Just below the LCD display is the voltage selector knob. The
right LCD display indicates the output current in mAs. The monitor is
connected to the power supply by one of the 4 pin Fischer sockets,
which has the same pinout as the ARRI cameras. The switch below the mA
meter selects which output is monitored. The LEDs indicates which
output's current is monitored. Below is a view of the backpanel.
The 4mm Banana plugs gives a regulated 12V output which can be used to
power a signal generator. The BNC connector is the video signal input,
that is send to the distribution amplifier.
LCD video monitors
I have been responsible for the design of the electronics of the
monitors below. These monitors were designed to be used as IVS monitors
for the film industry. It has a 4 pin Fischer connector to connect
directly to the IVS output socket of the ARRI cameras. There is also a
cable available for the Moviecam IVS socket. The monitor has two
inputs. Line A is 4-pin Fischer, while Line B is the BNC connector on
the back panel. The monitor has a signal indicator to indicate whether
a valid video signal is present on the selected channel. Therefore,
even if the camera's lens cap is still on and the image you receive is
black, you will know if the IVS feed is working. The monitor also has a
built-in color bar test signal generator which may be used to adjust
the monitor's settings. These monitors has a wide power supply range of
from about 9V to 35V.
Below the onboard colorbar test pattern of the monitor is activated.
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