Spruce Creek Microwave
HF Digital Preselector for Software Defined Radios
Tuning range:            1.8MHZ TO 30MHZ
Four Selectable      1.8-4MHZ, 4-10MHZ ,8-16mhz
Bands:                        16-30MHZ.
3 DB Band-width:      5% nominal or
Customer  Specified.
Insertion Loss:          4 DB Max.
Return loss:               10DB Max ref 50 Ohms.
IP3:                             +30 Min.
Control interface:      RS 232
Tuning Steps:            10KHZ.
Tuning Speed:           250us Max.
Transient response: Less than 1microvolt.
Built in HP filter for transient suppression.
Power:                       +5 VDC @ 750MA.
Connectors RF:        SMA Female.
Control connectors: Standard 9 pin D  
The Digital Preselector Filter is a tunable preselector filter
used to enhance receiver performance by reducing large
interfering signals that cause distortion. The preleselector
can be used in a variety of applications including software
defined radios (SDR), conventional receivers, and remote
co-located sites.
The Digital Preselector Filter contains a controller/power
supply and as many as four filter modules. Each module
supports 255 unique frequency settings. Each module is
calibrated to provide a tuning range with the least amount
of ripple across the band. When a new frequency is
requested, the controller selects the band and tuning
combination that tunes the filter to be centered as close as
possible to that frequency.  A new frequency is requested
by sending an ASCII command via RS-232 or USB.

A complete description of the communications protocol can
be downloaded.
Multiband Preselector
To Contact us:
Phone: 443-880-7120
Fax: 410-202-2502   
2733 Spruce Creek BLVD
Port Orange, FL
  • Built in Power Supply.
  • RS-232 Interface.
  • No Programing from external host.
  • Modular design for additional Frequency bands HF to UHF
  • 2 pole Chebyshev Low Ripple Frequency Response
  • Continuous Sweep and Hop ability.
  • Band-width from 2% to 10% available