20-200-1
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20-200-1 Wide-band VHF/UHF/L-Band Antenna The 20-200-1 Wide-band VHF/UHF/L-Band Antenna is a broadband passive blade antenna intended for use over the full VHF and UHF communications bands 30 MHz to 88 MHz, 108 MHz to 174 MHz and 225 MHz to 400 MHz, together with the frequency band 960 MHz to 1220 MHz. The antenna is fitted with a small, capacitively coupled, top tube which enhances low frequency performance while providing protection to the radiating structure in the event of a lightning strike. DO NOT SCALE DRAWING. REPORT ALL ERRORS TO D.O. 20-200-1 SHEET 2 CHELTON LTD. U1907 MARLOW U.K. 20-200-1PXX SER.No. UNTIL ANTENNA IS INSTALLED ON AIRCRAFT PROTECTIVE CAPS SHOULD BE FITTED TO CONNECTORS DIMENSIONS ARE IN MILLIMETRES INCHES ALUMINIUM ALLOY BASEPLATE, TREATED TUBE TOP WITH CHROMATE FILM CONVERSION TO DEF. STAN. 03-18 MUST MAKE GOOD ELECTRICAL CONTACT WITH AIRFRAME. ANTENNA SHOULD BE INSTALLED USING R.F. GASKET PART No. 6930A/20-200-1 POLYURETHANE ANTI-EROSION GASKET MUST BE ORDERED SEPARATELY FROM ANTENNA. LEADING EDGE STRIP THIS DRAWING IS C.A.D. GENERATED AND MAY ONLY BE AMENDED IN C.A.D. PASSIVE ANTENNA 7.7 EST 30-400/960-1220MHz TYPE 20-200-1 INSTALLATION DRAWING THIRD ANGLE PROJECTION Both radiating elements, together with certain passive matching networks, are implemented on a common PCB. The frequency dependent resistive network CHKD. DESN. LIGHTNING DIVERTER STRIP THIS CONFIDENTIAL DOCUMENT IS THE PROPERTY OF CHELTON LTD. WHO OWN THE COPYRIGHT THEREIN WITHOUT THE WRITTEN CONSENT OF CHELTON LTD. GIVEN BY CONTRACT OR OTHERWISE, THE DOCUMENT MUST NOT BE COPIED, REPRINTED OR REPRODUCED IN ANY MATERIAL FORM, EITHER WHOLLY OR IN PART & THE CONTENTS OF THE DOCUMENT, OR ANY METHOD OR TECHNIQUE AVAILABLE THEREFROM, MUST NOT BE DISCLOSED TO ANY OTHER PERSON. DRAWING. REPORT ALL ERRORS TO 9.3 MAX. Decoupling techniques are incorporated in the VHF/UHF element to avoid deleterious CHELTON THE CHELTON CENTRE, FOURTH AVENUE, interaction. MARLOW, BUCKINGHAMSHIRE, SL7 1TF, U.K. 10 DO NOT SCALE STANDARD FINISH:GLOSS WHITE EPOXY TO DEF. STAN. 80-161 18.4 MAX. OTHER FINISHES AVAILABLE ON REQUEST. SHEET 2 The L-band function is served by an elevated 3 EQUAL 0.27 REF 1.375 PITCHES REF feed monopole. 8 HOLES AL. ALLOY BUSHED 3.62 MAX AXES OF FIXING HOLES ARE VERTICAL 9.3 The antenna is essentially configuredMAX. TOP TUBE POLYURETHANE ANTI-EROSION as a broadband fan for VHF and UHF LEADING EDGE STRIP frequencies. Selective resistive loading 7.7 EST is applied to preserve match at low frequencies. This is progressively reduced LIGHTNING with increasing frequency and, at UHF DIVERTER STRIP C. frequencies, is bypassed. The capacitively OF G. coupled top tube enhances performanceCONNECTOR R.F. at R.F. CONNECTOR TNC FEMALE N FEMALE 10.95 MAX. low frequencies, and at UHF frequencies, is PART MARKING INFORMATION & 4.8 MAX. S/N 3.375 .188 electrically MARKED ON THIS FACE to preserve pattern decoupled 3 EQUAL PITCHES .55 MAX. integrity. FORWARD .46 MAX. OVER HEAD OF BUSH The copyright of antenna designs and images is copyright protected and owned by Chelton Limited. ©Chelton Limited. FORWARD CHELTON LTD. U1907 MARLOW U.K. 20-200-1PXX SER.No. 10.95 MAX. PART MARKING INFORMATION & 4.8 MAX. S/N MARKED ON THIS FACE 3.375 Chelton Limited has a policy of continuous development and stress that the information provided is a guide only .188 The Chelton Centre, Fourth Avenue, Marlow, 3 EQUAL PITCHES and does not constitute an offer or contract or part thereof. Whilst every effort is made to ensure the accuracy Buckinghamshire, SL7 1TF, UK .55 MAX. of the information contained in this Data Sheet, no responsibility can be accepted for any errors or omissions. UNTIL ANTEN ON AIRCRAF SHOULD BE F STANDARD GLOSS WH OTHER

is fitted to the base of the antenna to aid dissipation. Series low and high pass filters are fitted to the underside of the baseplate to provide isolation between the VHF/UHF and L-band functions. These filters are designed to exhibit a Tchebyscheff response and are constructed with low loss components to maintain gain performance. Radiation Pattern Power Rating Impedance VSWR Predominantly vertical (when mounted vertically) Omnidirectional in azimuth (nominal) 35 W CW max 30 MHz -88 MHz 120 W CW max 108 MHz - 174 MHz 1.5 kW peak 960 MHz - 1220 MHz 0.04 duty cycle > -22.5 30 Connectors...

LIGHTNING DIVERTER STRIP Wide-band VHF/UHF/L-Band Antenna C. OF G. 10.95 MAX. PART MARKING INFORMATION & S/N MARKED ON THIS FACE UNTIL ANTENNA IS INSTALLED ON AIRCRAFT PROTECTIVE CAPS SHOULD BE FITTED TO CONNECTORS DIMENSIONS ARE IN MILLIMETRES INCHES THIRD ANGLE PROJECTION THIS CONFIDENTIAL DOCUMENT IS THE PROPERTY OF CHELTON LTD. WHO OWN THE COPYRIGHT THEREIN WITHOUT THE WRITTEN CONSENT OF CHELTON LTD. GIVEN BY CONTRACT OR OTHERWISE, THE DOCUMENT MUST NOT BE COPIED, REPRINTED OR REPRODUCED IN ANY MATERIAL FORM, EITHER WHOLLY OR IN PART & THE CONTENTS OF THE DOCUMENT, OR ANY METHOD OR...