Flann Microwave 625-03 User manual

PROGRAMMABLE
SYSTEM ATTENUATOR
MODEL 625-03
INSTRUMENT MANUAL
Version 1.1
February 2022

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1 GENERAL INFORMATION ...................................................................................... 4
1.1 WARRANTY .................................................................................................................................... 4
1.2 DESIGN CHANGES .......................................................................................................................... 4
1.3 SPECIFICATION CHANGES .............................................................................................................. 4
1.4 REPAIRS ......................................................................................................................................... 4
2 GETTING STARTED ............................................................................................... 5
2.1 ETHERNET CONTROL...................................................................................................................... 5
2.2 MANUAL INTERFACE ..................................................................................................................... 6
3 ENVIRONMENTAL CONSIDERATIONS .................................................................... 7
4 SYSTEM FUNCTIONS AND FEATURES .................................................................... 8
4.1 POWER-UP PROCEDURE ................................................................................................................ 8
4.2 SETTING ATTENUATION ................................................................................................................ 8
4.3 INSTRUMENT ERRORS ................................................................................................................... 9
4.4 FIRMWARE UPGRADES .................................................................................................................. 9
5 ETHERNET COMMAND STRUCTURE .................................................................... 10
5.1 NOTATION ................................................................................................................................... 10
5.2 COMMAND SET ............................................................................................................................ 10
5.3 STATUS BYTE ................................................................................................................................ 12
5.4 COMMAND SUMMARY ............................................................................................................... 12
5.5 EXAMPLES .................................................................................................................................... 13
6 CARE OF THE INSTRUMENT ................................................................................ 14
7 REGULATORY INFORMATION ............................................................................. 15
7.1 DECLARATIONS OF CONFORMITY ............................................................................................... 15
7.2 WASTE ELECTRICAL AND ELECTRONIC EQUIPMENT (WEEE) REGULATIONS .............................. 17

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1 GENERAL INFORMATION
1.1 WARRANTY
Flann Microwave Ltd warrants each product of its manufacture to be free from defects in material and
workmanship. Our obligation under this warranty is limited to servicing or adjusting any products
returned to our address for that purpose, and to make good at our facility any part or parts thereof,
within one year of the date of delivery to the original purchaser, and which after examination shall be
shown to our satisfaction to have been thus defective. Warranty returns or repairs must first be
authorised by Flann Microwave Ltd, and then returned in accordance with our detailed instructions, with
transport charges prepaid. Flann does not authorise any third party to assume for them any other
liability in connection with the original sale than the foregoing. Unauthorised tampering with sealed
screws will invalidate the warranty and may result in damage to the product.
1.2 DESIGN CHANGES
Flann Microwave Ltd reserves the right to make changes in the design of its products without reference
to, and without incurring any obligation to make the same alterations on, products previously purchased.
1.3 SPECIFICATION CHANGES
Flann Microwave Ltd reserves the right to change any specification noted herein without prior notice.
1.4 REPAIRS
When wishing to return instruments for repairs, or for any other reason, please contact this Company for
shipping instructions. To expedite repair service, it is important to provide type number, serial number
and a detailed description of the reason, including all fault symptoms, for the return of the instrument.
Flann Microwave Ltd
Dunmere Road
Bodmin
Cornwall PL31 2QL
United Kingdom
Tel: [phone]
Fax: [phone]
Email: [e-mail]
http://www.flann.com
In USA contact:
Flann Microwave Inc
One Boston Place
Suite 2600
Boston
MA 02108 - 4407
Tel: [phone]
Fax: [phone]
Email [e-mail]
http://www.flann.com

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2 GETTING STARTED
Connect the 24V Power Supply provided with the 625-03 to the Power Input connector of the instrument.
Connect an Ethernet cable between your network Ethernet port (switch, router or adaptor) and the 625-
03.
The Ethernet interface is provided by a Lantronix xPICO 110 device. Under no circumstances should this
device be re-configured.
In the event that the label showing the instrument MAC address is accidentally removed from the
instrument, it is possible to run a utility that will read the instrument’s MAC address. This ‘DeviceInstaller’
program can be downloaded from:
https://www.lantronix.com/products/deviceinstaller/
When supplied from the factory, the device is configured to connect automatically to a network using the
DHCP protocol with dynamic IP address. The IP address assigned by your network can be found using the
DeviceInstaller program.
2.1 ETHERNET CONTROL
The following are examples of establishing communication with the attenuator using Telnet or RAW:
TELNET
To control the instrument using a Telnet connection, with a Telnet client (control program) such as PuTTY:
Enter the instrument’s IP address, e.g. 128.0.0.59, and the port number of 10001;
To test the connection type ‘identity?’ and press return. The instrument will return its identity
string, e.g. FLANN MICROWAVE, 625PRVA, 123456, V1.1 (where 123456 is the instrument serial
number).
The Windows Operating System includes a Telnet function which can be used from a Command Line
window. This feature may have to be turned on in Windows first.
Some clients do not echo the typed information, or at least not without changing default settings to
allow this. The \n terminator is not required in Telnet.
RAW
To control the instrument using a RAW connection, with a suitable client program such as PuTTY:
Enter the IP address, eg 128.0.0.59 and use port 10001;
You are now connected to the instrument;
To test the connection, enter ‘identity?\n’ and press return. The instrument will return its identity
string, eg FLANN MICROWAVE, 625PRVA, 123456, V1.1.
Note that the \n terminator is required for RAW commands unless using a program, such as PuTTY, that
terminates every command string.

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2.2 MANUAL INTERFACE
The screen displays the current position and the target position and has icons to signify when it is
receiving a remote command, or a state save is taking place.
The central button has three distinct functions, and they are accessed by hold time.
 A short/momentary press will cause the screen to flash and toggle between coarse (1 dB) mode
and fine (0.1 dB) step size
 Holding the button for 1-2 seconds will give a medium press which is signified by a colour
inversion. This will step through the display function
 Holding the button for in excess of 5 seconds will constitute a long press, which re-initialises the
instrument (i.e. it resets to the 60 dB reference position, or to the current position if HOLD_SET,
as described in 5.2 below, is ON).
The display function will cycle through brightness, revision information and then back to the standard
display.
The dB target can be set by rotating your finger around the touchpad. The target will change
immediately, and the current position will be seen to catch up. There is coarse selection for speed when
selecting whole dBs and a fine selection mode for adjusting in small increments.

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3 ENVIRONMENTAL CONSIDERATIONS
The Model 625-03 Programmable System Attenuator is designed to operate in ‘non-hazardous’ indoor
industrial or laboratory areas, or in a protected outdoor environment.
The operating environment must conform to the conditions shown in Table 1. Operation outside these
ranges cannot be guaranteed and may pose dangers to the operator or cause mechanical or electrical
failure of the equipment. The instrument can become warm during operation, and it is important to
maintain adequate ventilation at all times.
Environmental Condition Ranges
Temperature Operating +5°c to +35°c
Temperature Non-Operating 0 to +40°c
Humidity operating (max) 90 % without condensation
Humidity Non-operating (max) 95 % without condensation
Table 1: Environmental Limits

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4 SYSTEM FUNCTIONS AND FEATURES
4.1 POWER-UP PROCEDURE
When the instrument is connected to a local area network (LAN), it resets to the 60 dB reference position.
This action may be disabled if required, but the instrument must be reset as soon as possible to establish
the correct reference alignment. Refer to the ‘PWR_ON_RST’ and ‘RESET_INST’ commands in section 5.2.
The instrument is supplied with ‘PWR_ON_RST’ set to ON.
The instrument can be programmed to return to the last setting prior to power being removed. Refer to
the ‘HOLD_SET’ command.
4.2 SETTING ATTENUATION
The instrument can be set to attenuation values in the range 0.0 dB to 60.0 dB using the VALUE_SET
command. The smallest incremental value depends on the absolute attenuation: 0.01 dB (up to 20 dB
attenuation), 0.02 dB (20 to 30 dB attenuation), 0.05 dB (30 to 50 dB attenuation) and 0.1 dB (50 to 60 dB
attenuation). It is possible to position the instrument using motor steps in the range 0 to 9799, giving
increased resolution at lower attenuation settings. Refer to the ‘STEPS_SET’ command in section 5.2, and
Table 2 below. Note that the steps are from 0 dB, and the characteristic is non-linear.
Attenuation dB Steps Attenuation dB Steps Attenuation dB Steps
0.0 0 20.0 7952 40.0 9362
1.0 2139 21.0 8070 41.0 9398
2.0 2997 22.0 8181 42.0 9432
3.0 3635 23.0 8285 43.0 9464
4.0 4156 24.0 8384 44.0 9494
5.0 4602 25.0 8476 45.0 9522
6.0 4992 26.0 8563 46.0 9549
7.0 5340 27.0 8644 47.0 9574
8.0 5653 28.0 8721 48.0 9598
9.0 5938 29.0 8794 49.0 9621
10.0 6198 30.0 8862 50.0 9642
11.0 6437 31.0 8926 51.0 9662
12.0 6658 32.0 8987 52.0 9681
13.0 6862 33.0 9044 53.0 9699
14.0 7052 34.0 9098 54.0 9716
15.0 7229 35.0 9149 55.0 9731
16.0 7393 36.0 9196 56.0 9746
17.0 7547 37.0 9242 57.0 9761
18.0 7691 38.0 9284 58.0 9774
19.0 7826 39.0 9324 59.0 9787
20.0 7952 40.0 9362 60.0 9799
Table 2: Attenuation – Steps from 0dB

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When the high attenuation setting is active, this enables a coarse attenuation setting of up to 90 dB.
Refer to the ‘HIGH_ATTEN’ command. The attenuation accuracy beyond 60 dB is not guaranteed. The
front panel display colours are inverted when the attenuation is set to a value greater than 60 dB.
4.3 INSTRUMENT ERRORS
Instrument errors can be identified by interrogating the Status Byte (see information for the ‘INST_STAT?’
in section 5.2 and Table 3).
4.4 FIRMWARE UPGRADES
Users will be able to upgrade to the latest version of the Model 625-03 firmware over the Ethernet
interface by following the instructions given on the Flann Microwave Ltd website, www.flann.com.
A copy of the latest issue of this manual will also be available for download.

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5 ETHERNET COMMAND STRUCTURE
This section details the commands available and the valid operands that may be used with them.
5.1 NOTATION
Upper case bold characters represent the (program code) commands, which must appear exactly as listed.
Program code commands are not case sensitive, i.e. upper and lower case characters are accepted. The
input buffer is 50 bytes maximum.
Characters enclosed in the {} brackets are qualifiers attached to the basic command. A space may be
inserted between it and basic command, e.g. {ON|OFF} shows that either ON or OFF can be attached to
the root mnemonic.
For example, the ‘HOLD_SET’ command has three possible applications:
1. HOLD_SET ON - Switch on the Hold_Set
2. HOLD_SET OFF - Switch off the Hold_Set
3. HOLD_SET? - Query the present state of the Hold_Set
Each program command must be terminated with \n (Hex 0x0a), unless using Telnet
For example: ‘VALUE_SET45.3\n’
For instrument state commands (identified with ‘Query: Valid’), append the question mark character (?)
to the basic command without qualifiers to interrogate the state of the functions. The instrument
responds to the query as described for each command. For an ON/OFF command, the response is a ‘1’ or
a ‘0’ to indicate On or Off. For a settable function, such as VALUE_SET value, using VALUE_SET? returns
the function’s current value.
5.2 COMMAND SET
Note that for the Model 30625-03 only, the standard attenuation is 0 to 50 dB (rather than 0 to 60 dB),
and therefore 50 dB is the maximum setting unless HIGH_ATTEN is on.
VALUE_SET [value]
Sets the attenuation of the microwave instrument, in dB, to value
Query: Valid, returns setting
Value 0 to 60.0 (dB)
STEPS_SET [value]
Sets the attenuation of the microwave instrument, in steps, to value
Query: Valid, returns number of steps from reference
Value 0 to 9799
VANE_STEPS
Returns the vane position in steps without calibration.
Query: Valid, i.e. 60dB = 10099 when the calibration is -300
INCR_SET value
Sets the stored increment to value
Query: Valid, returns stored increment
Value 0 to 10 (dB)
INCREMENT
Increase the microwave instrument setting by the stored increment (dB only)
Query: Invalid

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DECREMENT
Decrease microwave instrument setting by the stored increment (dB only)
Query: Invalid
IDENTITY?
Outputs the identity string, e.g. ‘FLANN MICROWAVE, 625PRVA, 123456, V2.20’, where 123456 is the
instrument serial number, and V2.20 is the firmware version
Query: Valid, returns the identity string of the instrument.
*IDN
Outputs same as above
Query: Valid, returns identity string of the instrument.
SEEK_INDEX
Instrument will seek the index point on the encoder disc.
Query: Invalid, instrument will locate the index point
STORE_VAL value
Sets the stored setting to value.
Query: Valid, returns stored setting
Value 0 to 60.0 (dB)
REC_SETTING
Sets the instrument to the stored setting (dB)
Query: Invalid
HIGH_ATTEN {ON|OFF}
Sets the high attenuation feature on or off.
Query: Valid, returns ON or OFF
The front panel display colours are inverted when the attenuation is set to a value greater than 60 dB.
HOLD_SET {ON|OFF}
Returns the microwave instruments to the position when power was removed.
Query: Valid, returns ON or OFF
RESET_INST
Re-synchronise the instrument by driving to the reference position of 60.0 dB. This is the software
equivalent of cycling the power. It will also delete the ‘STORE_VAL’ from the memory back to default.
Query: Invalid
INST_STAT?
Request the value of the status register (byte)
Query: Valid, return the status register value, a value from 0 to 255 (see Table 3)

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5.3 STATUS BYTE
Bit Value Error
0 1 EEPROM error – failure to read or write to the EEPROM
1 2 Illegal value - Out of range request – incorrect value requested
2 4 Power on – a power-on has occurred since the last read of the register
3 8 Command error – incorrect syntax in a command line
4 16 Over temperature (60 °C). Cleared on temperature dropping below 55 °C.
5 32 Stepper stalled error
6 64 Error E2 – no encoder output found
7 128 Error E1 – encoder index not found
Table 3 – Status Byte interpretation
Note: The value of the Status Register will return to zero after being read.
5.4 COMMAND SUMMARY
Command Suffix Action Query
INCREMENT Increase setting by stored increment
DECREMENT Decrease setting by stored increment
VALUE_SET Value Switches to value mode and sets to value 
STEPS_SET Value Switches to steps mode and sets to value 
INCR_SET Value Stores increment in the present operating mode 
RESET_INST Reinitialise the instrument on the active channel
HIGH_ATTEN ON/OFF Enable or disable the high attenuation feature 
REC_SETTING Returns the instrument to the stored setting (see below)
STORE_VAL Value Store a setting determined by value (mode dependent) 
IDENTITY? (*IDN) Returns the instrument identity string 
INST_STAT? Returns the Status Register value from 0 to 255 
HOLD_SET ON/OFF Return instrument to last power-off condition 
SEEK_INDEX Seeks index same as power on
VANE_STEPS Returns vane position in steps without calibration 
Table 4 – Command Summary

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5.5 EXAMPLES
RESET_INST reset the instrument
VALUE_SET? returns a value of 60
VALUE_SET23.4 position to 23.4 dB
VALUE_SET? returns the value 23.4
STEPS_SET453 switch to steps mode and position to 453
STEPS_SET? returns the value 453
INCR_SET10 store an incremental value of 10 steps
INCREMENT move +10 steps
DECREMENT move -10 steps
A command string must be no more than 50 bytes. The command must be terminated by a newline (\n) when in RAW;
the \n terminator is not required when using Telnet.

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6 CARE OF THE INSTRUMENT
Internally, the 625-03 Programmable System Attenuator is a delicate instrument. When the waveguide
ports are not connected, it is recommended that flange covers (such as supplied with the instrument) are
fitted. This will help prevent inadvertent damage to the flange surfaces and internal vanes, and prevent
dust from entering the waveguide structure.

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7 REGULATORY INFORMATION
7.1 DECLARATIONS OF CONFORMITY

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7.2 WASTE ELECTRICAL AND ELECTRONIC EQUIPMENT (WEEE)
REGULATIONS
Flann Microwave is registered with the United Kingdom Environment Agency as a supplier of electrical
and electronic equipment, and makes the required declarations in accordance with WEEE Regulations.
Where this product was supplied to a customer in the United Kingdom:
When this product is at the end of its life, Flann Microwave will accept its return for safe disposal and
recycling. Please contact Flann Microwave for full instructions before returning any WEEE. The return
address is:
Flann Microwave Ltd
Dunmere Road
Bodmin
Cornwall PL31 2QL
Tel. [phone]
Where this product was supplied to a customer outside the United Kingdom:
Please follow local regulations regarding the disposal and recycling of WEEE, or contact your distributor
for advice.
Flann Microwave Ltd can provide information on the materials used in this instrument to assist in their
recycling or safe disposal.