Vertex Standard VX-5500U 5-5, Squelch Threshold

5-5

Alignment

Squelch Threshold

The squelch parameters can also be adjusted from

the computer by utilizing the Alignment Software.

Refer to the onboard help of the Alignment Software

Manual for details.

Tight SQL RSSI LEVEL (Wide)

ÌSelect the band center frequency channel (CH2),

and with the RF signal generator turned to the

same frequency, set the generator for ±3.0 kHz

deviation with 1 kHz tone modulation, and set

the output level for 3.0 dBµ at the antenna jack.

Threshold NSQ LEVEL (Wide)

ÌSelect the band center frequency channel (CH2),

and with the RF signal generator turned to the

same frequency, set the generator for ±3.0 kHz

deviation with 1 kHz tone modulation, and set

the output level for –8.0 dBµ at the antenna jack.

Tight SQL NSQ LEVEL (Wide)

ÌSelect the band center frequency channel (CH2),

and with the RF signal generator turned to the

same frequency, set the generator for ±3.0 kHz

deviation with 1 kHz tone modulation, and set

the output level for 0 dBµ at the antenna jack.

Tight SQL RSSI LEVEL (Narrow)

ÌSelect the band center frequency channel (CH5),

and with the RF signal generator turned to the

same frequency, set the generator for ±1.5 kHz

deviation with 1 kHz tone modulation, and set

the output level for 3.0 dBµ at the antenna jack.

Threshold NSQ LEVEL (Narrow)

ÌSelect the band center frequency channel (CH5),

and with the RF signal generator turned to the

same frequency, set the generator for ±1.5 kHz

deviation with 1 kHz tone modulation, and set

the output level for –8.0 dBµ at the antenna jack.

Tight SQL NSQ LEVEL (Narrow)

ÌSelect the band center frequency channel (CH5),

and with the RF signal generator turned to the

same frequency, set the generator for ±1.5 kHz

deviation with 1 kHz tone modulation, and set

the output level for 0 dBµ at the antenna jack.

ÌAdjust the squelch threshold level “Tight SQL

NSQ(Narrow)“ such that the squelch just open at

this signal input level (the BUSY LED will turn

on).

Contents

Main VX-5500U Service Manual Introduction UHF FM Transceiver Contents CONTROLS & CONNECTORS Front Panel 1-2 CONTROLS & CONNECTORS REAR (Heatsink) 1-3 BASIC OPERATION OF THE TRANSCEIVER Switching Power ON/OFF Setting the Volume Transmitting Selecting Groups and Channels 1-4 1-5 Channel Scan Dual Watch ARTS (Auto Range Transpond System) The PF Button Function 1-6 DIM EMG (Emergency) HA (Horn Alert) Home (Home Channel) Page 1-8 OPTIONAL ACCESSORIES 1-9 1-10 1-11 Page 2-1 Cloning DealerProgramming of VTP-50 and F5D-14 2-2 Specifications G RECEIVER (Measurements made per EIA standard TIA/EIA-603) TRANSMITTER (Measurements made per EIA standard TIA/EIA-603) 3-1 Exploded View & Miscellaneous Parts Page Page Page 4-1 Circuit Description Receiver PLL synthesizer 4-2 Circuit Description Transmitter DCS Demodulator CTCSS encoder/decoder MPU 5-1 Required Test Equipment Alignment Preparation & Precautions 5-2 PLL & Transmitter PLL Reference Frequency Alignment Channel Frequencies 5-3 Transmitter Output Power Transmitter Deviation 5-4 Receiver 5-5 Squelch Threshold Page 6A-1 6A-2 6A-3 ACE 3 Side A Parts Layout 6A-4 gb 5 Side B adcfe 1 6A-5 6A-6 6A-7 6A-8 6A-9 6A-10 6A-11 6A-12 6A-13 6A-14 6A-15 6A-16 6A-17 6A-18 6A-19 6A-20 6A-21 6A-22 6A-23 Page Page Page Page Page 6B-5 6B-6 6B-7 6B-8 6B-9 Page KEY Unit Page 6C-3 KEY Unit Page 6D-1 VR Unit Parts Layout Side A Side B MIC CONN Unit F2D-8 2-Tone Decode Unit 7A-2 VTP-50 VX-Trunk Unit 7B-2 FVP-25 Encryption / DTMF Pager Unit 7C-2 F5D-14 5-Tone Unit 7D-2 F5D-14 5-Tone Unit Page 7E-2 7E-3