background image

 

Model

 

A5

-12 Operation & Service Manual

 

 

A5-12 Manual A5 21 January 2005 

Page 4  

 

WARNING 

Instructions for adjustments when covers are removed and 
for servicing are for use by service-trained personnel only. 
To avoid dangerous electrical shock, do not perform such 
adjustments or servicing unless qualified to do so. 

 

WARNING 

Any interruption of the protective grounding conductor 
(inside or outside the instrument) or disconnecting of the 
protective earth terminal will cause a potential shock hazard 
that could result in personal injury. Grounding one 
conductor of a two conductor out-let is not sufficient 
protection. 

Whenever it is likely that the protection has been impaired, the instrument must be 
made inoperative and be secured against any unintended operation. 
If the instrument is to be energised via an autotransformer (for voltage reduction) 
make sure the common terminal is connected to the earthed pole terminal (neutral) 
of the power source. 
Instructions for adjustments while the covers are removed and for servicing are for 
use by service-trained personnel only. To avoid dangerous electrical shock, do not 
perform such adjustments or servicing unless qualified to do so. 
For continued protections against fire, replace the line fuse(s) with fuses of the 
same current rating and type (for example, normal blow time delay). Do not use 
repaired fuses of short-circuited fuse holders. 

1.2  Voltage, Frequency and Power Characteristics 

Voltage 220-240V AC  
Frequency 40-50Hz   
Power characteristics 500mA Max

  

1.3  Environmental Conditions  

1.3.1

 

Temperature 

Operating (ambient) 

-10°C to +55°C (-65 to +65 op) 

Storage 

-40°C to +85°C 

 

Summary of Contents for A5-12

Page 1: ...Model A5 12 Operation Service Manual A5 12 Manual A5 21 January 2005 Page 1 A5 12 12 Way Distribution Amplifier OPERATION SERVICE MANUAL...

Page 2: ...eplaceable Fusing Characteristics 5 1 5 Cleaning Instructions 5 2 Operating Procedure 6 2 1 Introduction 6 2 2 Input 6 2 3 Outputs 6 3 Circuit Descriptions 7 3 1 Output Amplifier 7 3 2 Mother Board 7...

Page 3: ...re to heed a warning Do not proceed beyond a warning until the indicated conditions are fully understood and met CAUTION Damage to equipment or incorrect measurement data may result from failure to he...

Page 4: ...erative and be secured against any unintended operation If the instrument is to be energised via an autotransformer for voltage reduction make sure the common terminal is connected to the earthed pole...

Page 5: ...uctions To ensure long and trouble operation keep the unit free from dust and use care with liquids around the unit Be careful not to spill liquids onto the unit If the unit does get wet turn the powe...

Page 6: ...plifiers in the following description A modified version of the output amplifier with a gain control called the input amplifier drives a twelve way passive power splitter This divides the signal with...

Page 7: ...d R3 set 100 output impedance for each transistor When combined in T1 a 50 output impedance results Due to the output impedance the gain of the output stages is 6 dB when the amplifier is loaded with...

Page 8: ...n The 50 output impedance of the input amplifier provides a good match to the passive splitter PS1 The main board is supplied from a 24V DC supply An off board regulator provides 18V R41 and R42 set t...

Page 9: ...l to 10 dBm and the spectrum analyser to sweep between 1 MHz and 100 MHz Adjust the A5 12 gain control VR1 to give an output level of 13 dBm at 10 MHz Measure the frequency response and verify against...

Page 10: ...mbinations of outputs choosing adjacent and remote outputs and verify against the specifications 4 2 5 Maximum Output Connect the 10 MHz signal source to the input of the A5 12 and the spectrum analys...

Page 11: ...dBm 3 Connect a spectrum analyser oscilloscope with 50 input impedance or RF power meter to any output 4 Adjust output level to 13dBm 1V RMS using the pre set VR1 on the main board 5 Replace the lid...

Page 12: ...m nominal into 50 1V RMS Output SWR 1 2 1 Maximum output 16dBm at 10 MHz typical 14dBm at 100 MHz typical Frequency Response 2 MHz to 100 MHz 1 5dB 500 kHz to 100 MHz 3dB Harmonics 10 MHz Source harmo...

Page 13: ...c above 1 MHz Broadband Noise 150 dBm Hz Delay Match Between Outputs 1ns Temperature Stability of Delay 10ps C Phase change at output due to open or short at any other output Calculated from isolation...

Page 14: ...Model A5 12 Operation Service Manual A5 12 Manual A5 21 January 2005 Page 14...

Page 15: ...Model A5 12 Operation Service Manual A5 12 Manual A5 21 January 2005 Page 15...

Page 16: ...Model A5 12 Operation Service Manual A5 12 Manual A5 21 January 2005 Page 16...

Reviews: