Procom BRF 70-3 User Manual
Brf 70/3

BRF 70/3
Band Reject (Notch-) Filter for the 450 MHz Band
DESCRIPTION
The BRF 70/3 is a 3-resonator notch-filter using full-length ¼ λ cavities.
This filter rejects a narrow band of frequencies and passes all others.
The filter can be applied both in connection with transmitters and
receivers to attenuate interfering signals which cause cross modulation
effects. The filter can be employed as a single component or it can act
as an integrated part of a complete multi-coupling system.
The BRF 70/3 can be tuned within the complete 400 - 470 MHz band.
Careful design and choice of materials ensure reliable operation over a
wide temperature range.
The housing is made of extruded aluminium, the chassis of brass, and
teflon insulation has been applied in the coaxial cables and in the
connectors.
The filter is black vinyl coated to prevent corrosion.
ORDERING DESIGNATIONS
TYPE
PRODUCT NO.
BRF 70/3
200001224
SPECIFICATIONS
ELECTRICAL
MODEL
BRF 70/3
FILTER TYPE
Band-reject (notch) filter
TUNING RANGE
400 - 470 MHz
MAX. INPUT POWER
50 W
INSERTION LOSS (out of reject area, 0-1000
MHz)
< 0.5 dB
REJECT ATTENUATION (Notch depth)
> 38 dB (See curve)
1 dB NOTCH BAND WIDTH
At 400 MHz: < ± 2.2 MHz
At 435 MHz: < ± 2.5 MHz
At 470 MHz: < ± 3.0 MHz
IMPEDANCE
Nom. 50 Ω
SWR
0-650 MHz: < 1.4
650-1000 MHz: < 2.0
MECHANICAL
TEMP. RANGE
–30° C → +60° C
CONNECTORS
BNC-female (others on
request)
DIMENSIONS (L x W x H)
230 x 77 x 33 mm
WEIGHT
Approx. 550 g
TYPICAL RESPONSE CURVES
PLEASE NOTE
The notch filter resonators can also be separately tuned to three different
frequencies in a “multiple notch” configuration, but the attenuation on each
frequency is then only approximately one third of the normal attenuation
when all notches work together.
PROCOM A/S reserve the right to amend specifications
without prior notice.
11/03/11