Products

Our product development takes place in top professional
R&D-departments, where our engineers are always working
to develop new innovative products in co-operation with our customers.

BRF 70/3

Band reject (notch-) filter for the 450 MHz band

  • 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.

DESCRIPTION

  • 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 N 200001233

SPECIFICATIONS

ELECTRICAL  
MODEL BRF 70/3 N
FILTER TYPE Band-reject (notch) filter
TUNING RANGE 400 - 470 MHz
MAX. INPUT POWER 50 W
INSERTION LOSS
(Outside reject bandwidth: Fc ± 5 MHz)
< 0.5 dB
REJECT ATTENUATION (Notch depth) > 38 dB (See curve)
1 dB NOTCH BANDWIDTH 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 N-female
BNC(f), TNC(f), SMA(f) on request
DIMENSIONS (L x W x H) 208 x 77 x 33 mm / 8.18 x 3.03 x 1.29 in.
(without connectors)
WEIGHT Approx. 550 g / 1.21 lb.

TYPICAL RESPONSE CURVES


MOUNTING DETAILS


 

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.

See what we are up to

Connect with us online, to get latest news

and see where the next exhibition is going to take place

Exhibition Calendar

We are Social

APN Logo Blue