User's Manual

800MHz & VHF Cell Enhancers

Maintenance Handbook

H/book Number:-50-078001HBKM

Issue No:-

Date:-02/09/2004

Page:-

49 of 88

5. SUB-UNIT MODULES

5.1 Bandpass Filters (02-007201 & 01-002503)

5.1.1 Description

The bandpass filters are multi-section designs with a bandwidth dependent upon the

passband frequencies, (both tuned to customer requirements). The response shape is

basically Chebyshev with a passband design ripple of 0.1dB. The filters are of slot coupled,

folded combline design, and are carefully aligned during manufacture in order to optimise

the insertion loss, VSWR and intermodulation characteristics of the unit. The tuned elements

are silver-plated to reduce surface ohmic losses and maintain a good VSWR figure and 50

load at the input and output ports.

Being passive devices, the bandpass filters should have an extremely long operational life

and require no maintenance. Should a filter be suspect, it is usually most time efficient to

replace the module rather than attempt repair or re-tuning.

5.1.2 Technical Specification (02-007201)

PARAMETER SPECIFICATION

Response Type Chebyshev

Frequency Range: 800 - 950MHz (tuned to spec.)

Bandwidth: 10-25MHz (tuned to spec.)

Number of Sections: 8

Insertion Loss: 1.0 dB

VSWR: better than 1.2:1

Power Handling: 100W max

operation: -10°C to +60°C Temperature

range:

storage: -20°C to +70°C

Weight: 3 kg (typical)

5.1.3 Technical Specification (01-002503)

SPECIFICATION PARAMETER

Response type: Chebyshev

Frequency range: 135 – 250MHz

Bandwidth: 3.5MHz (tuned to spec.)

N. of sections: 6

Insertion loss: 1.2dB

VSWR: Better than 1.2:1

Power Handling: 100W maximum

operate: -10°C to +60°C

Temperature range:

store: -20°C to +70°C

Weight: 3 kg

Size: 384 x 82.5 x 56.4mm