Burst MicroDA, VDA-2EQ, VDA-4, VDA-8 Users Guide

MicroDA,

VDA-2EQ,

Video Distribution
Amplifiers

VDA-4,

VDA-8

Manual Version 2.11

BURST ELECTRONICS INC
ALBUQUERQUE, NM 87109 USA
[phone] VOICE

Made in USA

[phone] TECH SUPPORT
[phone] FAX
www.burstelectronics.com

Hardware, software and manual copyright by Burst Electronics. All rights reserved. No part
of this publication may be reproduced or distributed in any form or by any means without the
written permission of Burst Electronics.

Video Distribution Amplifiers

Introduction

Burst Electronics manufactures a series of Video
Distribution Amplifiers. These units use the latest in
high speed monolithic operational amplifier
technology. The result is wide bandwidth, high gain
stability, low differential gain and phase. Models are
available from the MicroDA to the VDA-8 eight output
version. All units contain internal regulated bipolar
supplies and are powered by external 12 Vdc. Perfect
for field or studio applications. All models work in
either NTSC or PAL.

Four Output MicroDA
The four output MicroDA is a compact unit featuring a

looping input. A wide bandwidth of 33 MHz assures
clean video. Gain is adjustable ±3 dB. There is an
internal jumper to select
75 Ohm termination, an
external terminator is not
required.

Video Distribution Amplifiers

1

Four Output DA Model VDA -4 and VDA-4YC

The VDA-4 has the same features, performance,
and specifications as
the MicroDA. There
is a rear panel switch
to select an internal
75 Ohm termination
resistor on the loop
through input.
Optional Rack
Mounts available:
RM-4 (or RM-334, or
RM-344).

Options available: Y/C (S-VHS, Hi8), Rack Mount
Eight Output DA Model VDA -8
The VDA-8 has the same features, performance,

and specifications as the VDA-4, except with 8
outputs. There is
a rear panel
switch to select
an internal 75
Ohm termination
resistor on the
loop through
input.
Optional Rack
Mounts available:
RM-3 (or RM-334, or RM-344).

Options available: Rack Mount

Video Distribution Amplifiers 2

Two Output Model VDA -2EQ
The Model VDA-2EQ has the ability to equalize

video over RG­59 cable lengths
up to 1000 feet
(300 meters).

To Adjust:
The Model VDA-

2EQ has three
adjustments:
Gain, EQ, and
Rise Time. To
equalize for long
cable lengths, input either SMPTE Bars or
Multiburst. Use a Waveform Monitor and
Vectorscope, at the end of your cable, to view the
video signal while these adjustments are made.

• Adjust Gain to 1 volt (-40 IRE sync tip to 100
IRE White).

• Adjust EQ for correct vector lengths (or flat
waveform if using multi-burst).

• Adjust Rise Time (here SMPTE Color Bars
work best) for no overshoot when going from

setup to 100 IRE white (no chroma).

• Go back and tweak all three adjustments until
you have an undistorted video signal.

Video Distribution Amplifiers 3

Specifications:

Input: 1 Volt standard video (NTSC or PAL)
Input Impedance: HiZ (looping) or 75 Ohms, (jumper
selected)

Coupling: DC throughout
Internal Power: ±5 Vdc derived from external
12 Vdc

Outputs: Two, Four, or Eight, 75 Ohms
Output Voltage: 4 Vpp max
Delay Input to Output: 10ns
Output Impedance: 75 Ohms 1%
Frequency Response: DC to 33 MHz 0.2 dB
Gain: Unity, adjustable ±3 dB
S/N: 68 dB
Differential Gain: 0.03%
Differential Phase: 0.05°
Video Connector: BNC (4 pin MiniDIN
with Y/C Version)

Output Protection: Open or Short, infinite duration
Power: 120 VAC 60 Hz, 3 Watts, UL Listed
Wall Module (included)

DC Powered: 10 to 16 Vdc (polarity insensitive),
200 mA or less

Size MicroDA / 2EQ: 4.4W x 2.4H x 1.3D inches
Size VDA -4 / Y/C: 4.2W x 1.5H x 5.5D inches
Size VDA -4PC 0.75W x 3.95H x 4.95D inches
Size VDA -8: 5.6W x 1.5H x 7.0D inches
Warranty: One Year Parts and Labor

Video Distribution Amplifiers 5

NOTES