The DDS VFO 2 is designed as a companion VFO for the MST3 transceiver, although it may be used with many other rigs.
This is a full kit containing all on-board parts including blue backlit LCD and the DDS chip comes pre-installed on the PCB.
See the Shop page for pricing and availability.
Construction manual: DDS VFO 2 manual
Features: 1. Stable frequency – no more drift!
2. Simple to operate using a single rotary encoder control with press button switch.
3. Bright 16 character by 2 line LCD display. Can also be used with a non-backlight display to reduce current consumption if needed.
4. Output frequency range of 10KHz to 10MHz. Frequency range can be extended by ‘overclocking’ (see text).
5. Selectable 10KHz, 1KHz, 100Hz or 10Hz frequency steps.
6. RIT control allows fine adjustment of receive frequency without affecting the transmit frequency.
7. Display of power supply voltage.
8. Display state of USB/LSB and TX/RX inputs.
9. Programmable IF frequencies. Separate high and low side IF frequencies ensure the displayed frequency is the same as the transmitted frequency when changing sidebands.
10. Programmable option to save the current frequency and step value into memory. These are re-loaded at power up.
11. Fine adjustment of frequency in configuration to allow for master clock tolerances.
12. Voltage display can be trimmed in configuration to allow for voltage reference tolerance.
13. Can be configured without an IF Offset to allow use as a signal generator or with Direct Conversion transceivers.
14. Draws only around 50mA at 13.8V DC (with LCD backlight).
15. Spurious outputs at least -45dB.
16. Typically 300mV pk-pk sine wave output (200 ohms).
17. High quality double sided PCB with ground plane, plated through holes, solder mask and silk screen. v 18. Simple and easy to build using through hole components apart from one SMD chip. To assist constructors the PCB comes shipped with the SMD chip valready installed.