Novatech Instruments 2940A User manual

NOVATECH INSTRUMENTS
4210 198th St. SW #204
Lynnwood, WA 98036
USA
2940A Manual Rev 1.0
http://www.novatechsales.com/
[e-mail]
INSTRUMENTS, INC.
2940A DIRECT DIGITAL SYNTHESIZER
Instruction Manual
SECTION 1: INTRODUCTION
The Model 2940A can produce sinewave ouputs from 200kHz to 399.999999MHz in 1Hz steps. It has an
LCD display, rear mounted computer serial interface and front panel controls. The LCD display and
computer interface controls operate as independent units. The 2940A has two programmable frequen-
cies, “Fa” (top line of display) and “Fb” (bottom line of display), and two front mounted BNC output
connectors: one for the “A” frequency and one for the “B” frequency. There is also a BNC connector on
the rear panel that accepts an external reference input. Both the A and B frequencies will lock to the
external reference automatically if it is present.
The remote computer interface has priority and will automatically place the instrument in Remote Mode
if a valid command is received over the serial port.
SECTION 2: OPERATING INSTRUCTIONS
The user can use the computer interface or the the front panel controls to set the output frequency. When
using the front panel controls the user should depress a cursor button to move the underline character to
the number you would like to change and then use the rotary knob to change the number.
Note 1: The attenuation setting of 00 on the 2940A display to the right of the frequencies
are always present but are not functional.
Depressing the 2940A front panel MENU button allows the user to scroll through the available Instru-
ment settings and select a parameter for each setting. The MENU settings and parameters to select are:
Setting 1: Serial Baud Rate. Parameters: 300, 600, 1200, 2400, 4800, 9600 or 19200)
Setting 2: Remote Echo. Parameters: On or Off.
Setting 3: User Interface. Parameters: Local or Remote (Serial Port)
Setting 4: Power Up Mode. Parameters: Save (Current) Settings or Use Defaults.
Setting 5: External Standard. Parameters: Disabled, 1, 2, 5., 10, 1.544 or 2.048 MHz.
Note 2: It is recommended to only set the External Standard to Disabled or to 10. The set-
tings of 1, 2, 5, 1.544 and 2.048 are not tested and may not work.

NOVATECH INSTRUMENTS
4210 198th St. SW #204
Lynnwood, WA 98036
USA
2940A Manual Rev 1.0
http://www.novatechsales.com
[e-mail]
Note 3:
The Factory Default menu settings are:
1) Serial Baud Rate = 9600,
2) Remote Echo = On,
3) User Interface = Local,
4) Power Up Mode = Save Settings
5) External Standard = Disabled.
A 10MHz reference should be connected to the rear BNC before changing the External
Standard setting from Disabled to another setting. The frequency accuracy of the 2940A is
degraded when operating with an External Standard setting other then Disabled when no
External Standard is connected.
Note 4:
The SOF8 CD included with the 2940A contains an application named SOF8_1940A that
can be used to control the 2940A. The 1940A is a rack mount instrument that contains
two 2940A. The SOF8_1940A software supports two COM ports. It is recommended that
only one of these ports be given a valid COM port number when using this software with
the 2940A.

NOVATECH INSTRUMENTS
4210 198th St. SW #204
Lynnwood, WA 98036
USA
2940A Manual Rev 1.0
http://www.novatechsales.com
[e-mail]
SECTION 3: SERIAL COMMANDS
1: The serial protocol for all commands on the 2940A are 8 data bits, 1 stop bit, no parity. Baud rates
supported are 300, 600, 1200, 2400, 4800, 9600 and 19200. The commands are not case sensitive. The
default baud rate is 9600.
2: The commands ‘F’ ‘Fa’ ‘Fb’ ‘E’ ‘X’ ‘Aa’ ‘Ab’ and ‘S’ return ‘OK’ if parsed
and interpreted correctly. The commands can be terminated with CR, LF or CRLF in any order. This
allows use with PC systems, Linux or Unix.
3: The commands ‘Reset’ ‘Reset All’ and ‘C’ do not return a value and end by restarting
the instrument.
4: Incorrect commands will return an error code:
?0 Unrecognized Command
?1 Bad Frequency
?2 Bad Amplitude
?3 Input line too long
5: The command ‘Qr’ returns the values in the volatile RAM of the instrument. The values
returned reflect the present output and state of the 1940A and are as follows:
Fa 012.345678 1
Fb 012.345678 2
07 45 06 03 1B 05 01 00 01
The first two lines show the output frequency and attenuation setting of both channels in MHz to 1Hz
resolution. The next line has hexadecimal values showing the present state of internal registers. These
values will only be the same as those from the ‘Qr’ command if the values have been unchanged or a
‘S’ command has been executed (which could have been from a power down with save settings
enabled). Their interpretation in this example is:
07 internal settings
45 internal settings
06 internal settings
03 internal mode (‘03’=Remote)
1B internal settings
05 cursor position
01 baud rate register (‘00’=19200, ‘01’=9600, etc.)
00 control status
01 External Reference Setting: ‘00’=Use internal VCTCXO,
‘01’=5MHz,‘02’=10MHz,‘03’=1MHz, ‘04’=2MHz, ‘05’ =1.544MHz (T1),
‘06’ =2.048MHz (E1).

NOVATECH INSTRUMENTS
4210 198th St. SW #204
Lynnwood, WA 98036
USA
2940A Manual Rev 1.0
http://www.novatechsales.com
[e-mail]
6: The command ‘Qe’ returns the stored values in the non-volatile EEPROM of the instrument.
The values returned reflect the last saved state of the 2940A and are as follows:
Fa 012.345678 1
Fb 012.345678 2
07 45 06 03 1B 05 01 00 01 00 EF FF B7 14
The first two lines show the output frequency of both channels in MHz to 1Hz resolution. The next line
has hexadecimal values showing the saved state of internal registers. Their interpretation in this example
is:
07 internal settings
45 internal settings
06 internal settings
03 internal mode (‘03’=Remote)
1B internal settings
05 cursor position
01 baud rate register (‘00’=19200, ‘01’=9600, ‘02’=4800, ‘03’=2400, ‘04’=1200,
‘05’=600, ‘06’=300)
00 control status
01 External Reference Setting: ‘00’=Use internal, VCTCXO,‘01’=5MHz,‘02’=10MHz,
‘03’=1MHz, ‘04’=2MHz, ‘05’ =1.544MHz (T1), ‘06’ =2.048MHz (E1).
These (above) are the same as the ‘Qr’ command.
00 internal settings
EF internal settings
FF internal settings
B7 ‘B7’=save settings, ‘B8’=use defaults
14 Software revision, in this example 1.4
SECTION 4: WINDOWS SOFTWARE
The 2940A comes with a CD that contains the SOF8_1940 windows software. This software is intended
for use with both the 2940A and the 1940A. The 1940A has four programmable frequencies and two
COM ports. The 2940A has two programmable frequencies and one COM port. When using the
SOF_1940 software with the 2940A, it is recommended that only one of the COM ports be used. The
other COM port can be set to an invalid COM port number to prevent it from operating.

WARRANTY
NOVATECH INSTRUMENTS warrants that all instruments it manufactures are free from defects in
material and workmanship and agrees to replace or repair any instrument found defective during a period of
one year from date of shipment to original purchaser.
This warranty is limited to replacing or repairing defective instruments that have been returned by
purchaser, at the purchaser's expense, to NOVATECH INSTRUMENTS and that have not been subjected to
misuse, neglect, improper installation, repair alteration or accident. NOVATECH INSTRUMENTS shall
have the sole right to final determination regarding the existence and cause of a defect.
This warranty is in lieu of any other warranty, either expressed or implied, including but not limited to any
warranty of merchantability or fitness for a particular purpose. In no event shall seller be liable for
collateral or consequential damages.
All instruments manufactured by NOVATECH INSTRUMENTS should be inspected as soon as they are
received by the purchaser. If an instrument is damaged in shipment the purchaser should immediately file a
claim with the transportation company. Any instrument returned to NOVATECH INSTRUMENTS should
be shipped in its original shipping container or other rigid container and supported with adequate shock
absorbing material.
This warranty constitutes the full understanding between NOVATECH INSTRUMENTS and the purchaser
and no agreement extending or modifying it will be binding on NOVATECH INSTRUMENTS unless made
in writing and signed by an authorized official of NOVATECH INSTRUMENTS
NOVATECH INSTRUMENTS
4210 198th Street SW, Suite 204
Lynnwood, Washington 98036
United States of America
TEL: [phone]
http://www.novatechsales.com
[email protected]
Copyright 2014 Novatech Instruments