The HF-DDS is a complete high performance AD99954 DDS and Micro controller with software that can be used to construct a Radio Receiver or Transvceiver. The software emulates the Yaesu FT817 transceiver, and the microcontroller can be controlled using Ham Radio Deluxe software vie the RS232 connection. The hardware allows for vaious interfacing to circuitry that is commonly used in Radio design. Most of the functionality is dependant on the standard software that Mini-Kits supplies with the Kit.
The complete HF-DDS consists of a number of Kits and components that are available from Mini-Kits. The design consists of three PC board Kits using the Basic AD9954 DDS-VFO Kit, EME165 KIT, PIC18F4520 PIC Controller Kit, EME150 KIT, and EME159 KIT, PIC Control Board. There is an optional output expander Kit, EME169 KIT available to expand the EME150 PIC Controller.
The HF-DDS Kit is for experience constructors that already have experience in soldering SMD components, with many of the conventional sized SMD components being easily fitted. This Kit may be a challenge for some with soldering the AD9954 and interface chips to the DDS board, so Mini-Kits does offer a service at extra cost to fit just the chips. Some wiring is needed for the header connections between the boards, LCD and Keypad. It is suggested that a suitable crimping tool for 2.5mm header pins be used for reliability and to save time.
The maximum frequency that can be used is 175MHz, as this is gives acceptable output for the maximum 400MHz DDS clock frequency for the AD9954 chip. The software allows for a VFO for RX, and a separate VFO for TX that can have the VFO frequencies offset from the displayed frequency. This is useful for receivers or transmitters with an Intermediate Frequency, I/F. So yes it can be used on a receiver that has an e.g. 9MHz I/F by setting the RX display offset by 9MHz. A number of memories frequencies are also available for programming.
There is currently a final version of the software available to suit the PIC18F4520 PIC controller board.
Please refer to the HF-DDS Software documentation for further information.
All Software settings can be changed in the menu setting screens that are displayed on the LCD module. The keypad connected to the EME150 controller board along with the rotary encoder are used to change and memorize the menu settings into the PIC. No reprogramming of the PIC with a computer is required.
Below are the standard specifications for the software supplied by Mini-Kits. The HF-DDS Source code is available for download on the website for a nominal price to cover the development, and for future software updates.
How To Update The Software Download
AN851 Microchip Quick Programmer Software Download
Latest Firmware Update UPDATE_HF_DDS_VER_X_X.hex Download >There are currently no software updates after v1.J2 4/12/2009
PLease note: that if you try & update the software using a PIC programmer then you will erase the bootloader software that is pre-programmed into the PIC. The bootloaded is used to protect Mini-Kits from software piracy, & if you accidentaly do this then you will have to return your EME150 Microcontroller board to Mini-Kits to be reprogrammed.
1/ There are no current alerts for this Kit.
1/ A problem occured when the HF-DDS software when first powered up could not recognise the AD9954 chip. The fault was traced to a faulty TXB0108PWR level converter chip on the EME165 DDS board.
2/ No or low RF output from the AD9854 can be due to poor soldering of the chip to the board. Sometimes pressing down on the chip can increase the RF output indicating a poor solder joint on one of the pins.
3/ When turning the Rotary Encoder it either does not tune, or only tunes in one direction. Check that the diodes are correctly fitted on the EME159 control board. This can also be a problem with a faulty rotary encoder.
4/ LCD display has no characters, or only shows square blocks on the display top half. Please check that you have the wiring correct from the EME159 board to the LCD module. Many have incorrectly wired the LCD modules & damaged them.