Nokia 6235 Service Manual 07rm60ant

Nokia Customer Care

6235/6235i/6236i (RM-60)

Mobile Terminals

Antenna Description and

Troubleshooting

Issue 1 04/2005 Company Confidential ©2005 Nokia Corporation

6235/6235i/6236i (RM-60)
Antenna Description and Troubleshooting

Contents Page

Introduction ..................................................................................................................................................... 3

Visual Quality Requirements ....................................................................................................................... 3

Failures and Corrective Measures.............................................................................................................. 3

Antenna Position .........................................................................................................................................3

Internal Antenna ..........................................................................................................................................3

Damaged RF Feed, Ground Pins, or IHF Speaker Pins ........................................................................4

Damaged GPS antenna, pins, or heat stake .........................................................................................5

Obstructed IHF Speaker, RF Feed, and Ground Pads .........................................................................6

CDMA OR GPS RF Connector Failure ..................................................................................................... 7

Grounding of Display Frame .....................................................................................................................8

Testing the CDMA Antenna ......................................................................................................................... 8

Calibration Factors ......................................................................................................................................8

Calibration Factor for PCS1900 Frequency ..........................................................................................9

Measurement Procedure for Cell800/PCS1900 Mobile Terminals ................................................9

Testing GPS Antenna ..................................................................................................................................... 9

Calibration Factor for GPS ........................................................................................................................9

Measurement Procedure for GPS Antenna ........................................................................................10

Page 2 ©2005 Nokia Corporation Company Confidential Issue 1 04/2005

6235/6235i/6236i (RM-60)

Nokia Customer Care Antenna Description and Troubleshooting

Introduction

The mobile terminal incorporates an internal antenna. This antenna arrangement is used
for AMPS/CELL and PCS frequency bands. The internal antenna assembly consists of a
Planar Inverted-F Antenna (PIFA) used for the cellular engine and an Inverted-F antenna
(IFA) used for the GPS engine, which is placed on the side of internal antenna body.

Visual Quality Requirements

Following are the minimum acceptable visual quality requirements of the internal
antenna assembly:

• Gloves must be used when handling antennas. Do not touch the antenna radiator
with bare hands.

• No visual cracks or mechanical defects.

• No oil, dirt, or particles are present on the parts.

• Radiator must be aligned with the plastic housing.

• GPS antenna contacts must be inside the plastic housing.

• Radiator must be flat with no warping.

• All pins must be at the same level.

Failures and Corrective Measures

Antenna Position

The internal antenna is assembled into the B-cover as shown in Figure 1. If no internal
antenna is installed, the antenna gain will be degraded by more than 25 dB.

Internal antenna

Figure 1: B-cover assembly

If the internal antenna is missing, install one. If the radiator looks obviously damaged,
then replace the internal antenna.

Internal Antenna

The internal antenna includes a planar-inverted F antenna (PIFA) radiator and an
inverted F antenna (IFA), which is the GPS antenna radiator, attached to a plastic carrier.

Issue 1 04/2005 ©2005 Nokia Corporation Company Confidential Page 3