4.4 GHz RF Synthesizer Signal Generator with built in RF Power Detector

Description

The Windfreak SynthNV is a 138MHz to 4.4GHz software tuneable RF signal generator controlled and powered by a PC running Windows XP or Windows 7 via its USB port. It includes an on board RF power detector which can be used with the sweep function as a basic RF network analyzer. It can also run as a CW generator stand alone on a battery.
Use this device as a generic RF signal generator in your test setup, or use it as a high quality local oscillator in your RF / microwave communication system. Simultaneously measure and graph RF power in real time.
The software is easy to install and use. It can control multiple devices, do an RF CW frequency, run an RF sweep, save to EEPROM, register real time power measurements and fine tune the PLL registers for experienced users. Control is very similar to a bench top signal generator. It is also touch panel friendly.
This software was written in Labview and the open source code is included so that you can modify and enhance any way you see fit. If you don't own Labview, you will also get an executable that will install stand-alone and run on a PC. If you want to write your own software, it is best to get Labview and reverse engineer the Windfreak Labview source code. If not, the device is easy to talk to via 1 simple command byte followed by PLL program data, a power setting byte or return responses from the power detector.
RF power (max) into a 50 ohm load is similar to this: 17.0dBm @ 137.5MHz, 19.0dBm @500MHz, 19.0dBm @ 1GHz, 18.0dBm @ 2GHz, 17.0dBm @ 3GHz, 11.0dBm @ 4GHz (note: amplitude is adjustable via software over 2 amplitude ranges of 30dB in 1/2 dB steps for more than 60dB of adjustment.)
RF generator accuracy is based on an onboard 2.5ppm 10MHz crystal oscillator which is also routed to the outside world via the reference SMA connector.  This connector can also be used to input a higher precision reference if so desired.
Even when used without the aluminum extruded case, no sideband spurs can be found in a typical lab EMI environment. 4 mounting holes are provided on the PCB.
The synthesizer will run off of USB power. It will also run standalone via its DC power connector and low dropout linear regulator. The required voltage is a range from 6-9 volts DC, with the center pin being positive and the outer conductor being ground. 12 volts is possible with enhanced heat sinking on the regulator.
There is also a 1MHz - 4GHz broadband RF power detector enabled by an Analog Devices ADL5513. This RF detector has up to 70dB of dynamic range and can measure up to +10dBm of RF power. The software will report real time power measurements or can be calibrated to show gain over frequency between the input and output connectors which will give a basic ability to measure the performance of filters and other RF devices. The display will show RF power vs frequency, or gain vs frequency much like a lab quality network analyzer. By using an external circulator or coupler, there will also be the ability to measure the return loss / VSWR of RF devices such as antennas in possible future versions of the software.  All new versions of software will be free to anyone that has proof of purchase for the SynthNV.
The onboard microcontroller is an ATmega32U4 and comes programmed with Windfreak Technologies proprietary firmware to allow basic control of the whole device. In conjunction with that, it also has the Atmel boot loader so that custom firmware can be loaded through USB by the end user. Many of the pins from the microcontroller go to .100" inch headers spread throughout the PCB. These pins can be custom configured by the end user as generic digital I/O, A/D convertors, or PWM outputs. All the headers are on .100" inch centers so perf board can be used for prototyping of special function daughter cards. Other functions that go to these headers are: SPI port, ISP (In System Programming) port, reset, boot load, and a basic FM analog connection to VCOs vtune port.
USB communication is done via a virtual comm port directly to the microcontroller. Drivers are included with the software.
Included with all of this is a hardcopy of the PC board schematics and a PCB reference designator map. This way you can see what bus wires are used to control the synthesizer chip and PA. You will also see what microcontoller pins are routed to headers. This helps with custom firmware development.
On board the PCB are 4 troubleshooting LEDs: one that shows USB power, two generic LEDs [3] from the microcontroller, and one that shows phase lock on the programmed frequency. The generic LEDs will blink differently with different commands. They will also show errors when the command is not understood. This helps with custom software development.
Compare this unit to other solutions worth thousands of dollars.
All ebay sold units are latest version hardware, firmware, and software.
Some applications include: wireless communications systems, software defined radio (SDR), radar, automated test equipment, computer controlled sweeping and hopping, Phase Lock Loop Synthesizer Design, Local Oscillator replacement, and hobbiest radio development.