Cross Country Wireless SDR-4+ general coverage receiver...frequency range extended to 70.5 MHz
The SDR-4+ is an HF general coverage SDR receiver covering from 0.85 to 70.5 MHz.
It has a Si570 low noise synthesised VFO, relay switched band pass filtering, ultra high IP3 E-PHEMT RF amplifier and a built-in USB soundcard.
Key design features include:
Antenna isolation transformer with a 50 ohm impedance input for use with coax fed antennas
Extra antenna isolation when the receiver is powered down
Relay switched RF band pass filters
RF amplifier now using a ultra high IP3 E-PHEMT RF amplifier in the receiver front end
Built-in USB stereo soundcard
3.5mm soundcard audio output for headphone monitoring or connection to datamodes program
3.5mm IQ audio output for connection to external high sampling rate sound cards
Built in a compact aluminium case 175 x 106 x 30 mm
In March 2012 following customer feedback and design work on our HF/VHF/UHF Multicoupler we have revised the SDR-4 and released the SDR-4+. This has a revised RF front end using a ultra high IP3 E-PHEMT RF amplifier, an IQ audio output to feed external sound cards and other revisions to improve RF performance, gain distribution, IQ balance and the SDR display.
August 2013...Following recent customer feedback and design work on a new project we are releasing a new version of the SDR-4+. This has improved frequency coverage up to 55 MHz including the 6m amateur band, a revised USB sound card and a new antenna isolation transformer with a 2 kV working voltage rating without the 450 ohm antenna input.
September 2013...As a result of development work on the CW Sentry SDR transceiver the frequency range of the SDR-4+ has been extended to cover the 4m amateur band. The frequency coverage is now 0.85 to 70.5 MHz.
The price of the revised SDR-4+ receiver is £179.95 plus shipping. At current rates that's $278.92 or 208.74 Euro.
Frequency range: 850 kHz to 55 MHz
Input impedance: 50 ohms
Clipping RF level: -13 dBm
Maximum frequency display: 48 kHz internal sound card, up to 192 kHz external sound card
Minimum discernable signal: -135 dBm
Input IP3: +14.5 dBm (measured with two -20 dBm carriers with 5 kHz spacing at 14 MHz)
Receiver modes: Depends upon the SDR software used with the receiver
Supply voltage: 5 Volts (from USB ports)
Supply current: 320 mA (from USB ports)
Connectors: BNC female (RF in 50 ohms), two USB B ports, two 3.5mm stereo jacks
Overall dimensions: 185 mm (L) x 110 mm (W) x 38 mm (H)
As the E-PHEMT RF amplifier used in the SDR-4+ is a "dual-use" device i.e commercial and military under the EU Dual-Use Regulation - currently Council Regulation (EC) No 428/2009 we cannot export the receiver to certain prohibited countries. We also need proof of customer identity. Payments by PayPal with a confirmed address meet the identity proof requirement.
The SDR-4+ receiver set-up FAQ sheet can be downloaded as a PDF file here .
The SDR-4+ receiver Quick Start Guide v1.6 can be downloaded as a PDF file here .
The SDR-4+ setup program can be downloaded as a zip file here . This installer program stores the USB drivers in a folder C:/SDR-4+ and places the ExtIO files in the HDSDR and Winrad folders in Program Files and Program Files (x86). When the SDR-4+ receiver is plugged in for the first time direct the driver installation wizard to C:/SDR-4+/Driver and the USB driver will load automatically if the PC is in Administrator mode.
The SDR program we recommend for first time users of SDR receivers is HDSDR which can be downloaded here .
A block diagram of the SDR-4+ receiver can be downloaded here .
A SDR-4+ receiver running on the WebSDR system can be accessed here .
Existing users of SDR-4 receivers can return them for upgrade to the SDR-4+ specification for £20.00 ($31.40 or 24.00 Euro) plus the cost of return shipping.
This offer also applies even if you didn't buy the receiver direct from Cross Country Wireless.
Contact Chris Moulding, G4HYG via info@
Please note that we have no connection with the eBay seller Pandatron or Pandatroncz based in the Czech republic. They are selling a receiver called the SDR-5+. It's in a similar case to our SDR-4+ and even has yellow antenna sockets. Unfortunately it appears to be a blatant case of plagiarism. If there is any doubt please check their eBay feedback!
Contact Chris Moulding, G4HYG via info@
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