Substitute a standard VGA monitor for an OEM unit

[[email protected]]

I'm working on a display monitor which is used in a wheel alignment
machine in a garage. The unit is a type of VGA monitor which was
manufactured by Kristel Corp. It has problems and I would like to see
if I can substitute a standard VGA monitor in its place. It uses a
special connector which according to the schematic has the following
connections:
1- Red in
2- Red ground
3- Green in
4- Green ground
5- Blue in
6- Blue ground
7- Common ground, (common with video grounds)
8- H-sync in
9- V-sync in
10- NC
There is a 75 ohm resistor from each color input to ground. All
grounds are common.
I found a pinout for a 15 pin VGA connector. It is marked:
Standard VGA
monitor pinout
---------------------
1 Red Video
2 Green Video
3 Blue Video
4 Monitor ID - Bit 2
5 Ground
6 Red Ground
7 Green Ground
8 Blue Ground
9 [KEY]
10 Sync Ground
11 Monitor ID - Bit 1
12 Monitor ID - Bit 0
13 Horizontal Sync
14 Vertical Sync
15 N/C (Reserved)

I would like to try to use a standard VCA monitor for this
application. Can I use the substitute monitor by connecting its RGB
inputs to the alignment machine electronics RGB connections, then tie
all the grounds together, and then connect the h and V sync to their
appropriate pins? Do I need to worry about the other connections? The
OEM monitor doesn't seem to use any of them The following is what I
have in mind:

Standard VGA Oem cable from
from alignment machine
monitor pinout
--------------------- ----------------------------
1 Red Video 1- Red out
2 Green Video 3- Green out
3 Blue Video 5- Blue out
4 Monitor ID - Bit 2 - N/C
5 Ground 7- Common ground
6 Red Ground 2- Red ground
7 Green Ground 4- Green ground
8 Blue Ground 6- Blue ground
9 [KEY] - N/C
10 Sync Ground - conn. all gnds together
11 Monitor ID - Bit 1 - N/C
12 Monitor ID - Bit 0 - N/C
13 Horizontal Sync 8- Hor. sync
14 Vertical Sync 9- Vert sync
15 N/C (Reserved) - N/C

I'm not sure about the Hor sweep rate but I think that its compatible.
Would an old type multisync monitor. (of the type that I scrapped
years ago) have been a better choice for this conversion? I also have
an old RGB monitor with separate BNC connectors on the back for RGB
and V and H sync. Might that also work? If anyone has some further
information on this I would be very grateful. Lenny

 

[Franc Zabkar]

I'm working on a display monitor which is used in a wheel alignment
machine in a garage. The unit is a type of VGA monitor which was
manufactured by Kristel Corp. It has problems and I would like to see
if I can substitute a standard VGA monitor in its place.

There is a 75 ohm resistor from each color input to ground. All
grounds are common.

.... inside the monitor and video card but not in the cable.

I would like to try to use a standard VCA monitor for this
application. Can I use the substitute monitor by connecting its RGB
inputs to the alignment machine electronics RGB connections, then tie
all the grounds together, and then connect the h and V sync to their
appropriate pins? Do I need to worry about the other connections? The
OEM monitor doesn't seem to use any of them

Keep the sync ground and RGB grounds separate. Also run separate video
grounds for each RGB signal. Use mini-coax for the RGB connections.

I'm not sure about the Hor sweep rate but I think that its compatible.

You can measure the horizontal frequency of the wheel alignment
machine at the VGA connector.

Would an old type multisync monitor. (of the type that I scrapped
years ago) have been a better choice for this conversion?

You may find its specs here:
http://www.monitorworld.com/monitors_home.html

I also have
an old RGB monitor with separate BNC connectors on the back for RGB
and V and H sync. Might that also work? If anyone has some further
information on this I would be very grateful. Lenny

This monitor could be one of those fixed frequency types. I'd power it
up and aim a CRO probe at the CRT. The radiated flyback pulse will
tell you the free running frequency of the horizontal oscillator. One
problem with fixed frequency monitors is that they usually expect
negative sync whereas a VGA card can produce sync pulses of either
polarity depending on the video mode.

- Franc Zabkar

 

[Clint Sharp]

In message

I'm working on a display monitor which is used in a wheel alignment
machine in a garage.

What is the make and model of the wheel alignment machine?

 

[[email protected]]

In message


What is the make and model of the wheel alignment machine?

Its a Hunter D111

 

[Baron]

I'm working on a display monitor which is used in a wheel alignment
machine in a garage. The unit is a type of VGA monitor which was
manufactured by Kristel Corp. It has problems and I would like to see
if I can substitute a standard VGA monitor in its place. It uses a
special connector which according to the schematic has the following
connections:
1- Red in
2- Red ground
3- Green in
4- Green ground
5- Blue in
6- Blue ground
7- Common ground, (common with video grounds)
8- H-sync in
9- V-sync in
10- NC
There is a 75 ohm resistor from each color input to ground. All
grounds are common.
I found a pinout for a 15 pin VGA connector. It is marked:
Standard VGA
monitor pinout
---------------------
1 Red Video
2 Green Video
3 Blue Video
4 Monitor ID - Bit 2
5 Ground
6 Red Ground
7 Green Ground
8 Blue Ground
9 [KEY]
10 Sync Ground
11 Monitor ID - Bit 1
12 Monitor ID - Bit 0
13 Horizontal Sync
14 Vertical Sync
15 N/C (Reserved)

I would like to try to use a standard VCA monitor for this
application. Can I use the substitute monitor by connecting its RGB
inputs to the alignment machine electronics RGB connections, then tie
all the grounds together, and then connect the h and V sync to their
appropriate pins? Do I need to worry about the other connections? The
OEM monitor doesn't seem to use any of them The following is what I
have in mind:

Standard VGA Oem cable from
from alignment machine
monitor pinout
--------------------- ----------------------------
1 Red Video 1- Red out
2 Green Video 3- Green out
3 Blue Video 5- Blue out
4 Monitor ID - Bit 2 - N/C
5 Ground 7- Common ground
6 Red Ground 2- Red ground
7 Green Ground 4- Green ground
8 Blue Ground 6- Blue ground
9 [KEY] - N/C
10 Sync Ground - conn. all gnds together
11 Monitor ID - Bit 1 - N/C
12 Monitor ID - Bit 0 - N/C
13 Horizontal Sync 8- Hor. sync
14 Vertical Sync 9- Vert sync
15 N/C (Reserved) - N/C

I'm not sure about the Hor sweep rate but I think that its compatible.
Would an old type multisync monitor. (of the type that I scrapped
years ago) have been a better choice for this conversion? I also have
an old RGB monitor with separate BNC connectors on the back for RGB
and V and H sync. Might that also work? If anyone has some further
information on this I would be very grateful. Lenny

I would check that pinout against the one for an EGA monitor !

 

[Clint Sharp]

I would check that pinout against the one for an EGA monitor !

Or even CGA. Might be worth finding a TV with an RGB input and seeing if
it syncs.

 

[Franc Zabkar]

Its a Hunter D111

Can you upload the circuit diagram(s) for the monitor? Alternatively,
do you have the part number for frequency sensitive components such as
the flyback transformer, deflection yoke, oscillator chip?

- Franc Zabkar

 

[[email protected]]

In message <[email protected]>, Baron

Or even CGA. Might be worth finding a TV with an RGB input and seeing if
it syncs.

I do have an old Sony commercial RGB monitor down in the basement.
Looks like Columbus may have brought this one over with him. It has 5
BNC inputs, for RGB and V and H sync. I don't know if its multisync or
not. Seriously though it must be at least 15 to 20 years old. I
considered trying it. Lenny

 

[Baron]

I do have an old Sony commercial RGB monitor down in the basement.
Looks like Columbus may have brought this one over with him. It has 5
BNC inputs, for RGB and V and H sync. I don't know if its multisync or
not. Seriously though it must be at least 15 to 20 years old. I
considered trying it. Lenny

I don't know whether they are still available, but you could get a cable
with 5 colour coded BNC on one end and a 9 pin cga/vga plug on the
other. These monitors are usually fixed frequency, sync on green
devices.