Broken Or Missing Bottom Antenna Clip Or Matching Circuit - Nokia 6255 Description And Troubleshooting

Nokia Customer Care
Figure 7: PWB layout of the RF feed pad and the matching circuit
The matching circuit is right next to the RF feed pad. The matching circuit consists of a
shunt inductor of 27nH, a series cap of 1.2pF, and a series inductor of 5.6nH. If the
matching circuit is not installed properly or any of the components are missing, the
extended antenna gain will be degraded by about 25dB and the retracted antenna gain
will degrade by about 15dB.
• If corrosion is present or the pad is missing, replace the PWB and the mobile
terminal.
• If either pad is obstructed or covered, clear and/or clean the pad.

Broken or Missing Bottom Antenna Clip or Matching Circuit

If the bottom antenna clip does not contact the whip stopper when the whip is fully
retracted, the internal antenna gain will degrade by about 4-5dB at Cell band and
3-10dB at PCS band when the whip is retracted.
The bottom matching circuit is right next to the bottom antenna clip and consists of a
series cap of 3.3pF and series inductor of 1.5nH. If the bottom matching circuit is not
installed properly or any of the two components are missing, then the retracted antenna
gain will degrade by about 15dB.
Issue 2 05/2005
©2005 Nokia Corporation
6255/6255i/6256/6256i (RM-19)
Antenna Description and Troubleshooting
Matching circuit
Company Confidential
RF feed pad
Page 7