Nokia RM-154, 6275, 6275i Vari Antenna Description and Troubleshooting

Nokia Customer Care

6275/6275i (RM-154)

Mobile Terminals

Antenna Description and

Troubleshooting

Issue 1 - September 2006 Company Confidential

6275/6275i (RM-154)
Antenna Description and Troubleshooting Nokia Customer Care

Contents Page

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

CDMA Antenna on the E-Cover Assembly............................................................................................... 4

Damaged CDMA Radiator Bezel Assembly ...........................................................................................4

Missing or Damaged CDMA Antenna and IHF Pogo Pins ................................................................4

IHF Module ....................................................................................................................................................5

Obstructed RF Feed and Ground Pads ...................................................................................................5

Damaged RF Connector .............................................................................................................................5

Auxiliary Antennas: GPS, BT, and FM ....................................................................................................... 8

GPS Antenna .................................................................................................................................................8

Bluetooth Antenna ......................................................................................................................................9

FM Antenna ...................................................................................................................................................9

Circuit Diagrams and Chip Locations ..................................................................................................10

SAR Reduction Foil...................................................................................................................................... 13

Page 2 Company Confidential Issue 1 - September 2006

6275/6275i (RM-154)

Nokia Customer Care Antenna Description and Troubleshooting

Introduction

This troubleshooting guide addresses potential failures that affect antenna performance
of the 6275/6275i mobile terminals and discusses methods for correction of these
failures. Following are the three serviceable antennas used in the 6275/6275i mobile
terminals:

• CDMA antenna (on the E-cover assembly)

• GPS antenna (on the antenna module)

• Bluetooth antenna (on the D-cover assembly)

The following sections describe these antennas and their connections to the mobile
terminal components.

Issue 1 - September 2006 Company Confidential Page 3

6275/6275i (RM-154)
Antenna Description and Troubleshooting Nokia Customer Care

CDMA Antenna on the E-Cover Assembly

The E-cover (or antenna cover assembly) is comprised of the E-cover plastic part, the
CDMA antenna (or CDMA radiator) and the bezel assembly. The bezel assembly includes
the camera, flash windows, and the bezel.

The E-cover connects to the D-cover assembly via six tabs located on the four corners
and top edge of the E-cover, as well as a snap-in feature located on the bottom two
corners.

Antenna pogo pins

Ground pin

Feed pin

Figure 1: CDMA antenna on the E-cover

Damaged CDMA Radiator Bezel Assembly

The CDMA flex radiator antenna and bezel assembly are glued to the inside surface of
the E-cover. To remove the E-cover assembly from the D-cover, use the SRT-6 opening
tool to release the two snap-in tabs that secure the E-cover to the D-cover.

If either the CDMA radiator or bezel assembly is damaged, replace the E-cover assembly.

Note: You cannot replace the CDMA radiator or the bezel individually. You must
replace the entire E-cover assembly.

E-cover assembly

To reattach the E-cover assembly to the D-cover, align the E-cover above the D-cover
and apply a vertical force to engage the snap-in feature.

Missing or Damaged CDMA Antenna and IHF Pogo Pins

The CDMA antenna is connected to the PWB through two pogo pins. The CDMA antenna
pogo pins are housed in the D-cover (see Figure 1 on page 4).

If a CDMA antenna pogo pin is damaged or missing, replace the D-cover. An improper
connection between the CDMA antenna and the PWB due to a damaged or missing pogo
pin degrades the CDMA antenna performance by 5dB to more than 15dB.

Page 4 Company Confidential Issue 1 - September 2006

6275/6275i (RM-154)

Nokia Customer Care Antenna Description and Troubleshooting

IHF Module

The IHF module impacts the CDMA antenna performance. If there is any damage to the
IHF module, replace the acoustic module.

GPS Antenna
Flex Strip on
side of IHF

Figure 2: IHF module

Obstructed RF Feed and Ground Pads

The CDMA antenna ground and feed pogo pins touch the PWB on ground and feed pads.

• If the main antenna feed pad is obstructed, removed, or covered, the CDMA
antenna feed pogo pin does not touch the PWB and the antenna gain degrades
by more than 15 dB.

• If the CDMA antenna ground pad is obstructed, removed, or covered, the ground
pogo pin does not touch the PWB and the antenna gain degrades by more than
5dB.

• If corrosion is present or the pads are missing, replace the PWB.

• If either pad is obstructed or covered, clear or clean the pads.

• If the CDMA antenna matching network is missing or damaged, replace the
component.

• If the PWB is permanently damaged, replace the PWB.

Damaged RF Connector

The CDMA RF connector could fail by not connecting the RF input to the RF output of
the RF connector. If this happens, the antenna gain degrades by about 15dB. You can
check this by testing for DC conductivity between the RF connector’s RF input and
output.

Issue 1 - September 2006 Company Confidential Page 5