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NOVATECH INSTRUMENTS

4210 198th St. SW #204

Lynnwood, WA 98036

USA

                             2940A Manual Rev 1.0
                http://www.novatechsales.com/

sales@novatechsales.com

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.

Summary of Contents for 2940A

Page 1: ...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 ...

Page 2: ...ing 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 ...

Page 3: ...t 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 p...

Page 4: ...ngs 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 ...

Page 5: ...s 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 shi...

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