Rosendahl bonsaiDRIVE - Manual (Page 6)

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5. Connecting a monitor
Professional monitors are expensive. For this reason people like to
use consumer TVs with an AV input.
Attention! Consumer TV equipment is generally safety class II, i.e.
without earth connection. This is easily confirmed by looking at the 2
pole mains plug.
Earth potential differences up to 100 volts can occur and ground
currents will flow when such TV equipment, when switched on, is
connected to your earthed studio environment.
For example when you connect the consumer TV to the studio
equipment via a BNC connector it is not guaranteed that the shield
makes contact first. In this case the signal input on the middle pin can
be subjected to several hundred volts which no input will survive, the
result being that expensive studio equipment and computer hardware
can be destroyed!
If you still intend using a consumer TV as a monitor it is
imperative that the AV ground is permanently connected to the
studio ground at all times.
This connection can be made using the ground of an audio
input to the TV set (cinch socket shield connection) which can
be permanently connected to the mains earth/ studio ground.
Switch off the TV set. Remove mains plug. Connect the
permanent earth then the AV connection to the studio system.
Then reconnect the TV to the mains and switch on.
The video outputs of the bonsaidrive have 75
Ω source impedance
and must be connected using 75 Ω coax cable and be connected to
single 75 Ω terminated inputs. With connection to 2 inputs in parallel
(2x75 Ω ) the video picture will be 6 dB darker and with a single input
without 75 Ω termination the picture will be 6 dB brighter.
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bonsaidrive supports 4 different analog video formats:
(1) Composite Video (CVBS, German FBAS), a “normal” video
signal. All picture and sync information is transmitted over a single
75
Ω cable. Connection over C17 (CVBS).
(2) Y/C Video (German S-Video) is normally outputted by a small
mini DIN socket and is a 2 signal 75
Ω analog video standard, a
brightness signal (Y) and a colour signal (C). Connections over C16
(Y) and C15 (C)
(3) Component Video (German Komponentensignal) is formed out of
3 component signals (Y, Pb, Pr). Y is brightness, Pb and Pr are two
colour difference signals (Y-blue, Y-red). Connection over C17 (Y),
C16 (Pb), C15 (Pr).
Note: This analog video transmission standard offers the highest
picture quality and should always be used when the monitor has an
component video input.
(4) RGB Video is also a three signal 75
Ω video transmission
standard and offers the same advantages as Component Video. R is
red, G is green with sync siganls, B is blue.
Note: Not to be confused with a computer VGA connection!
RGB video is often used in the SCART connection in consumer TV
equipment and can be connected to the bonsaidrive using a SCART
to BNC adapter cable.
Connections are: C17 (G), C16 (B), C15 (R).
Now connect the monitor to the bonsaidrive with 75
Ω cables and
switch on. If no stable picture is shown, select the required output
format in the “ANALOG OUTPUT FORMAT” menu i.e. COMPOSITE
and Y/C,COMPONENT or RGB.
Note: In order to guarantee at least a black and white picture use the
CVBS/Y output C17 connected to a Y or CVBS input of the monitor.