Nokia 7088 Istruzioni operative

Nokia Customer Care

7088 (RM-219)

Mobile Terminal

Antenna Description and

Troubleshooting

7088 (RM-219)

Antenna Description and Troubleshooting

Contents Page

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

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

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

Internal Antenna................................................................................................4

Damage of the antenna feeding pins.................................................................4

Obstruction of the RF signal path..............................................................................5

RF Connector Failure........................................................................................6

7088 (RM-219)

Nokia Customer Care Antenna Description and Troubleshooting

Introduction

The mobile terminal incorporates an internal antenna. This antenna arrangement is

used for Cellular frequency bands. The internal antenna assembly adopts planar

inverted-F antenna (PIFA) structure used for the cellular engine, and it is embedded

invisibly in a mechanical part.

Visual Quality Requirements

Followings are the minimum acceptable visual quality requirements of the internal

antenna assembly:

 No visual cracks or mechanical defects.

 No oil, dirt, or particles on the parts.

 No paint drops on the mechanical appearance.

 Good elasticity for two feeding pins (signal and ground pins).

 Invisibility for the antenna at any condition.

Failures and Corrective Measures

Figure 1 shows the D Cover antenna assembly. The internal antenna is a sticker

type flex film mounted on the D Cover, and there is an antenna decoration on top of

it. D Cover, antenna, and antenna decoration are with the same color (shown in

Figure 1 are all black). Thus, ideally the antenna is invisible.

 If the appearance of the antenna decoration looks damaged or peeled off,

replace it with a new antenna decoration.

Antenna zone

 If the antenna can be seen at some condition, remove the current antenna

decoration, and stick a new one on its proper position.

Antenna decoration

D Cover

Figure 1: D Cover Assembly

7088 (RM-219)

Antenna Description and Troubleshooting

Internal Antenna

The internal antenna receives and transmits the signal by the contact between two

feeding pins of the D Cover and the feeding pads on the PWB. Figure 2 shows the

feeding pins (signal and ground pins) and their corresponding feeding pads. Two

feeding pins must contact fully with their corresponding pads on the PWB. If one of

the connections is malfunction, the antenna performance could be degraded by

more than 20dB.

Signal pin Ground pin Ground pad Signal pad

Figure 2: The connection structure for D Cover assembly and PWB

Damage of the antenna feeding pins

The two feeding pins must properly connect to their corresponding pads on the

PWB.

 If one of the connections is malfunction, the antenna performance could

be degraded by more than 20dB.

 If one of these two pins lacks for elasticity, change the D Cover assembly.

 If the DC resistance between these two pins is more than 0.5 ohm,

change the D Cover assembly.

 If one of these two feeding pins is broken or bent, change the D Cover

assembly.

7088 (RM-219)

Nokia Customer Care Antenna Description and Troubleshooting

Obstruction of the RF signal path

If the RF signal path is obstructed, broken, damaged, the cellular antenna

performance degrades.

 If the obstruction, damage of signal path happens, replace the PWB.

 If one of the components at the matching circuit is missing, broken,

replace proper component according to the latest reference document.

 If the DC resistance between signal pad and the output port of RF switch

is more than 1 ohm, replace the PWB.

Figure 3: PWB layout of RF feeding path

Signal pad Output port of RF switch

Matching circuit

7088 (RM-219)

Antenna Description and Troubleshooting

RF Connector Failure

The RF connector fails when it does not properly connect the RF input terminal to

the RF output terminal during the SMT. If this happens the antenna gain degrades

by 25 dB. Check this by testing the resistance value between the RF input and RF

output ports of the RF connector and see if the value is close to zero. If the RF input

is not connected properly to the RF output, replace the RF connector.

Note: Perform the resistance value test without a RF cable attached to the RF

connector. Because the RF connector is also a switch, the RF output is

disconnected from the RF input when a RF cable is inserted into the RF connector.

 RF input terminal – connect to duplexer.

 RF output terminal – connect to the antenna pad through antenna

matching circuit.

 RF connector terminal – connect to a RF coaxial cable.

RF output terminal RF input terminal

RF input terminal

Figure 4: RF input / output terminal

Note:

• MSM6025 is underfilled and cannot be replaced.

• Memory IC is underfilled and cannot be replaced.

• The Baseband Shielding Cover Assy and RF Shielding Cover cannot be

reused after removal.

• After using the heatgun, replace the domesheet

Altri manuali per 7088

Questo manuale è adatto per i seguenti modelli

Indice

Manuali Palmare popolari di altre marche

Honeywell

Honeywell Dolphin 9900 Manuale utente

Honeywell

Honeywell CN75 Manuale utente

MiTAC

MiTAC Mio 168 Manuale utente

Wasp

Wasp WDT92 Manuale utente

Texas Instruments

Texas Instruments TI-Nspire Manuale utente

AXEM Technology

AXEM Technology MBS Manuale utente

Armstrong

Armstrong Brain Wave Istruzioni per il montaggio

Unitech

Unitech TB128 Manuale utente

Symbol

Symbol MC9000-G Manuale di installazione e funzionamento

Unitech

Unitech HT1 1D Batch Manuale utente

Ingenico

Ingenico IWL220 GPRS Manuale utente

Intermec

Intermec CK61 Manuale utente

Symbol

Symbol c2000 Manuale utente

Symbol

Symbol MC18 Manuale di installazione e funzionamento

Acer

Acer n20 Manuale utente

Intermec

Intermec CK61 Manuale utente

Docomo

Docomo F-04H Manuale utente

Toshiba

Toshiba e350 Series Manuale utente