INSTALLATION AND OPERATING
MANUAL
P25 Series UHF
CONTINUOUS DUTY
POWER AMPLIFIER
Crescend Technologies
140 E. State Parkway
Schaumburg, IL 60173
Tel:
847-908-5400
Fax:
847-908-5408
[email protected]
www.crescendtech.com
040003A010 Rev A
Page 1: ...ERATING MANUAL P25 Series UHF CONTINUOUS DUTY POWER AMPLIFIER Crescend Technologies 140 E State Parkway Schaumburg IL 60173 Tel 847 908 5400 Fax 847 908 5408 sales crescendtech com www crescendtech co...
Page 2: ...User Manual 040003A010 Rev A Page 2 of 25...
Page 3: ...OOTING 18 4 1 INTRODUCTION 18 4 2 TROUBLESHOOTING 18 4 3 RETURN FOR SERVICE PROCEDURES 20 4 3 1 OBTAINING RMA 20 4 3 2 REPACKAGING FOR SHIPMENT 20 5 MAINTENANCE 21 5 1 INTRODUCTION 21 5 2 PERIODIC MAI...
Page 4: ...the rear of the amplifier The fan assembly draws ambient air in from the front and blows the air across the heat sink fins out the back of the amplifier NOTE The manufacturer s rated output power of...
Page 5: ...direct connections to the branch circuit e g use of power outlet strips Reliable grounding of rack mounted equipment should always be maintained To install the amplifier proceed as follows 1 Mount th...
Page 6: ...axial cable must be connected to ground at the entrance of the building in which the equipment is installed This should be done in accordance with applicable national electrical installation codes In...
Page 7: ...plied HIGH INPUT Yellow LED Illumination indicates RF input power exceeds safe level 125 of rated input power Alarm active until RF input removed LOW OUTPUT Yellow LED Can activate if power drops due...
Page 8: ...Low Output Power RF Input Power Above Maximum Rating High Temperature Amplifier Shutdown High VSWR or No Power Supply Voltage 10 FWD PWR Forward Power Voltage 11 HI VSWR Alarm High VSWR 12 RF DRIVE M...
Page 9: ...rature has exceeded maximum operation threshold The amplifier output is shutdown To reset the alarm it is necessary for the amplifier to cool down to below the maximum safe operation threshold Off Nor...
Page 10: ...limitations Open Maximum output power Signal is pulled up internally to 10V Pull down signal with appropriate circuitry 0 10V Adjusts output power setting 2 REV PWR Analog Output Reverse Power Voltag...
Page 11: ...FWD PWR Analog Output Forward Power Voltage 0 10V Uncalibrated analog voltage that is proportional to the forward power detected at the amplifier output 100 kOhm 100pF 11 HI VSWR Digital Output Alarm...
Page 12: ...ow Output Power 0 8V Alarm the analog control loop is open and unable to adjust the output power level Alarm is turned off only when the analog control loop is closed Check if drive level is within no...
Page 13: ...aracters are sent by the amplifier only in response to commands Commands and responses are terminated by a carriage return r If characters are sent to the amplifier before the carriage return r and do...
Page 14: ...y default at the factory PS W r Example PS 250W r PS W r Example PS 250W r Set power level The value range is from 050 to 250 with step 010 The controller will round any numbers that do not meet this...
Page 15: ...RPM r Return fan 1 speed F2 r F2 RPM r Example F2 03500RPM r Return fan 2 speed FT r FT RPM r Example FT 03500RPM r Return CHECK FAN alarm speed threshold PF r PF r Example PF 1 r Return PA FAULT alar...
Page 16: ...anual 040003A010 Rev A Page 16 of 25 COMMAND RETURNED ANSWER NOTES ED r ED r Example ED 0 r Return EXCITER DRIVE condition state 0 RF input signal present 1 no RF signal at PA input represents a singl...
Page 17: ...r to the maximum output power level POWER SET potentiometer pulls down the POWER CTL signal located in the Monitor connector section 3 2 and 3 3 To ensure the full output power adjustment range from 2...
Page 18: ...N EXCITER DRIVE RF DRIVE OUTPUT POWER STATUS PA FAULT CHECK FAN HI TEMP HI VSWR HI INPUT LOW OUTPUT OTHER SYMPTOMS POSSIBLE CAUSE SUGGESTED ACTIONS ON ON Full power Low Amplifier is in transmit mode N...
Page 19: ...OFF No power High Fuse failure Disconnect AC cord Check fuse and replace if necessary No AC power is applied to amplifier Verify AC power source Power Supply failure Obtain RMA to have amplifier check...
Page 20: ...w power Low Low signal is applied to POWER CTL pin Remove any voltage or short attached to POWER CTL pin POWER SET potentiometer is turned counter clockwise Turn POWER SET potentiometer fully clockwis...
Page 21: ...tachment Check RF connectors to make sure that they are tight Inspect the lightning protection system and ground at the site 5 3 CLEANING AIR INLETS OUTLETS The air inlets and outlets should be checke...
Page 22: ...ed and used Crescend power amplifier products meet all government established RF exposure levels In addition Crescend recommends specific operating instructions for users of its power amplifier produc...
Page 23: ...r amplifier will be generating measurable RF energy exposure when transmitting 3 The maximum permissible exposure MPE radius is unique to each base site installation and is based on several factors su...
Page 24: ...f the MPE Radius for a 250 Watt 406 MHz Transmitter WARNING Failure to observe the minimum safe distance radius may result in exposure to RF radiated energy in excess of the FCC Maximum Permissible Ex...
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