On Oct 6, 1:43 pm, "gb" wrote:
wrote in message

ps.com...





Hi
I Have successfully completed a DDS with the following facilities. It
uses Mcrocontroller PIC16F877A and AD 9850/9851 DDS chip. The main
facility in this DDS VFO is any settings including chip type and DDS
clock can be changed even after programming the Microcontroller CHIP.
Please click on the link below for more details.

http://hamradioindia.org/forums/viewtopic.php?=&p=2428

Here is some details.

1) DUAL VFO, that is VFO A, VFO B and A=B facilities.

2) UP to 50 RX frequency storage on MEMORY.

3) The Software allows 2 modes of operation,

a) VFO MODE, where the encoder is used to adjust the frequency.

While in this mode, VFO A or B is displayed on the top line of the
LCD.

b) MEMORY MODE, where the encoder is used to select a previously saved
frequency. While in this mode, MEM is displayed on the top line of the
LCD.

4) KEYPAD Frequency entry and additional 7 Press buttons for other
functions.

The remaining Functions included in the KEYPAD itself.

5) UP/DOWN fast search in three different steps using KEYPAD which is
user selective.

6) SCAN and quick UP/DOWN search in three different steps with auto
Repeat on PTT.

7) Frequencies are entered in MHz, the * is used to enter a decimal
point,

and the # is used to ENTER the completed frequency.

If the first digit entered is the #, the number entered will be
negative.

8) S- Meter reading from S0 to S9+40db in logarithmic db range.

9) Variable rate tuning to use the cheep mechanical encoder.

10) Step size can be changed from 1Hz to MHz range.

11) RIT facility.

12) VFO copy to MEMORY and from MEMORY to any VFO (A/B) facility.

13) AM/LSB/USB/CW modes Operation with PIC pin outputs for switching.

14) Allows -Ve and +Ve IF OFFESTS. Offset frequency = any value from
min RX frequency to Max 999MHz

15) 10 RX BANDPASS filter selection for RX coverage from 1.5MHz to
30MHz. Usefull to set up an All band RX.

16) BAND PASS filter switching selectivity 1Hz and 1ms switching
speed, which allows cross band Operation.

17) CW OFFSET adds to TX Frequency when transmitting thus avoids
modulated CW.

18) Save to MEMORY and Copy from MEMORY functions.

19) Scan VFO frequency and Scan MEMORY facility

20) Time out function for ignoring any wrong entry in system settings.

21) Auto repeat function for respective keys.

22) Display Multiplier Option to use with VHF rigs

23) Menu screen allows user to change any settings in the setup
screen.

24) All settings can be changed in the SETUP screen at any time even
when the DDS is in working mode including DDS chip type and Reference
Clock.

25) LBS/USB/CW Crystal switching (USB is treated as CW).

26) CW OFFSET adds to TX Frequency when transmitting thus avoids
modulated CW.

I will be giving the software FREE along with the PCB. Interested
homebrewers may Email me for Circuit and other details.

I can send the PCB anywhere in the world using Registered INDIA POST.

SHAJI.P.BVU3WIJ
KOZHIKODE, INDIA.
E mail: and (mark copy in both id)

Are you still providing the PCB and PIC chip w/source (as mentioned in
April) ??

Greg
w9gb- Hide quoted text -

- Show quoted text -

The links seem to be broken. I googled and found him posting recently
at http://www.hamradio.in/forums/search..._author=vu3wij .

Tom VE3MEO