SRK Electronics FMA501, Руководство пользователя

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SRK Electronics FMA501 manual
 2007 SRK Electronics Pty Ltd 11
4.8 Protection
The FMA501 incorporates a number of protective features that make it extremely rugged.
If the reflected power from the antenna exceeds 50W then the output RF power will be
automatically reduced to bring the reflected power back to 50W. Under this condition the
FMA501 will continue to function, albeit at a reduced output power, indefinitely until the
reflected power reduces. The LCD will show “SWR HIGH”.
The forward power is limited to 550W. “RF HIGH” will be shown on the LCD under this
condition. RF input power should be reduced.
If the RF input power exceeds 20W, the amplifier will totally shutdown until the input power is
reduced to less than 10W.
If the temperature of the RF amplifier becomes excessive, then the RF output power will be
reduced to zero until the amplifier temperature falls to an acceptable level. During this time
the LCD will show “TEMPERATURE HIGH”. The upper limit for heatsink temperature is
85°C.
If the AC line voltage drops below 200V then the amplifier will shut down until line volts
exceeds 210V. The LCD will show “UNDER AC VOLTS”.
If the AC line voltage exceeds 275V then the amplifier will shut down until the line volts falls
below 260V. The LCD will show “OVER LINE VOLTS”.
4.9
Remote operation.
The FMA501 may be monitored and controlled remotely via the “TELEMTRY” connector on
the rear of the unit. This is an RS232 standard connection with the following characteristics:
Baud rate:
9600
Data bits: 8
Parity: NONE
Stop bits: 1
Flow control: NONE
The pinout for the DB9 connector is as follows: pin 2, transmit data, pin 3, receive data, pin 5,
common (0V). All other pins are not connected.
The FMA501 responds to the following commands. <CR> indicates the ASCII character 0D
hex. All letters are upper case, spaces (20 hex) are indicated by “_”. All commands must be
terminated by <CR>. Note that a line feed (0A hex) must not be sent before or after <CR>.
After a response is sent, a carriage return, line feed and “>” are sent.
FP?<CR>
Returns forward power in the form XXXW<LF><CR>>. For example:
FP?<CR>
(command)
500W<LF><CR>
(response from amplifier)
>
Note that for forward powers of 99W and below, the leading zero is replaced with a space
RP?<CR>