Antenna Bandwidth And Requirements - Lectronics Octopack Instruction Manual

OCTOPACK

Antenna Bandwidth and Requirements

The design of Lectrosonics wideband multicouplers
helps deal with a changing RF spectrum, however, it
also introduces the requirement for specific or more
advanced antennas to provide maximum operating
range. Simple whip antennas cut to a single frequency
block are inexpensive and effective at covering a 50 to
75 MHz band, but will not provide adequate coverage
for the entire range of a wideband antenna multicou-
pler. Following are the antenna options available from
Lectrosonics.
Model
A500RA(XX) and Whip
A8U(xx)
ACOAXBNC(xx) Coaxial
SNA600 Tunable dipole
ALP500 Log-periodic
ALP620 Log-periodic
ALP650 (w/ amp) Log-periodic
ALP650L (w/ amp) Log-periodic
In the table, (xx) with the whip and coaxial antenna
model numbers refers to the specific frequency block
that the antenna is precut to use. The SNA600 model
is tunable to move the center frequency of its 100 MHz
bandwidth up and down from 550 to 800 MHz.
The greater the mismatch of frequencies between the
antenna and the receiver, the weaker the signal will be,
and the shorter the maximum operating range of the
wireless system. Experimentation and checking the
range before the production starts is always a good
idea, and is mandatory if the frequencies of the antenna
and receiver do not match exactly. On many production
sets, the short operating range that is needed may allow
the use of a slightly mismatched whip antenna.
In general, using a whip antenna one block above or
below the receiver range will provide adequate range,
often with no noticeable difference from the correct
antenna.
Use the RF level meter on the receiver to check the
received signal strength. Keep in mind that the signal
level varies wildly as the system operates, so be sure to
conduct a walk test through the area to identify loca-
tions where the signal drops to very low levels.
There are also many antennas made by other compa-
nies, which are easily found by searching for web sites.
Use search terms like "log-periodic," "directional,"
"broadband," "discone," etc.
http://www.ramseyelectronics.com/downloads/
manuals/DA25.pdf
10
Type Bandwidth
MHz
30 to 35 (typi-
cal)
30 to 35 (typi-
cal)
100
450 - 850
450 - 850
537 - 767
470 - 692
ALP500
ALP620
LECTROSONICS, INC.
A500RA
(precut to block)
ACOAXBNC
(precut to block)
SNA600
ALP650