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Introducing the IQPro

Next Generation, 0-30 MHz VFO Using an AD9854 Direct Digital Synthesizer

By Craig Johnson, AAØZZ

See my article about the IQPro in May/June 2006 QEX magazine above

What is a DDS VFO? Very briefly, in simple terms, a Variable Frequency Oscillator (VFO) is an electronic
mechanism that creates a sine wave at a desired frequency. This VFO is designed to be used as
a "tuner" for a radio transmitter or receiver. In the past, VFOs have been constructed using variable
capacitors or coils that are moved to change the frequency. This VFO uses a newer technology, a
very tiny Direct Digital Synthesis (DDS) chip, controlled by a small computer (microcontroller),
to create the sine wave at the desired frequency.

IQPro Features   (Updated 10/21/2005)

1) The IQPro is a 3" x 6" board, split into two halves. The "control" half contains the two PICs and headers for the pushbuttons, LCD, LEDs, and band-switching. The "RF" half contains the AD9854 DDS and the amplifiers. The intent is to allow the builder to put the RF portion into an "RF-tight" box. This split also opens up the possibility of driving the "RF board" directly from a PC (serial or parallel port) or from another control board.

2) The entire board runs on 5v (12v optional). Has a 3.3v regulator (no heat sink) for the AD9854.

3) No MMIC amplifiers. Instead it has three options for boosting the AD9854's I and Q outputs up to +7 dBm or higher. (Parts are supplied for all three options.)

Option 1: Toroids only. 12v power not needed. I and Q outputs of +7 dBm.

Option 2: Transistor amplifiers only. 12v power is needed. I and Q outputs of +7 dBm.

Option 3: Toroids AND transistor amplifiers. 12v power is needed. I and Q outputs of approximately +17 dBm.

4) No pushbuttons on the board (except a reset button). Instead it has a header to support a 24 pushbutton array (4 rows x 6 columns) which is ready for easy customization and movement to the front panel. The kit includes a PC board for mounting the pushbuttons but it is not required.

5) 12 pushbuttons (3 columns x 4 rows) form a telephone-like keypad for direct frequency entry.

6) 12 additional pushbuttons for UP/DN MHz, UP/DN Band, VFO-A/VFO-B Toggle, VFO-A = VFO-B, Fast-tuning toggle, Mode cycle (LSB, USB, CW-, CW+), Split toggle, Tone set, Backlight toggle, and Calibrate toggle.

7) No LEDs on the board. Instead there is a header to support 9 LEDs to be mounted on the front panel.

8) Nearly all through-hole parts. Exceptions are the AD9854, the 125-MHz clock, and one MOSFET for enabling the LCD backlight.

9) Two 16F877 PICs, an Interface PIC and a Driver PIC. The Interface PIC handles the encoder, the pushbuttons, the LEDs, and the band-switching. The Driver PIC handles the AD9854 and the LCD. The two PICs "communicate" with messages.

10) Output signals are sent to a header when the VFO frequency changes to a different frequency band. These signals can set/reset latching relays on an external board (not supplied) to engage band-specific receiver pre-amps or transmitter output filters (for harmonic suppression).

11) A mode-cycle pushbutton operates a latching relay which reverses the I and Q signals. If the mode is LSB or CW- the relay is latched in the "normal" position. If the mode is USB or CW+, the relay is latched in the "reverse" direction.

12) Sidetone. The frequency is shifted (plus or minus) by a selected amount when running in CW and Receive mode. The amount of offset (tone) is adjusted by pushing a pushbutton and then turning the encoder. The tone value is saved in EEPROM so it is not lost by power-down. The offset value is SUBTRACTED from the base (transmit) frequency if in CW- mode and ADDED to the base (transmit) frequency if in CW+ mode. This allows you to listen to CW signals on either sideband.

13) LCD (16 x 2) with backlight toggled on/off via pushbutton.

14) 12v to 5v switching power supply kit included (about 1" square"). It is meant to be mounted at some convenient location in the case.

15) The manual has MANY design details including the theory of operation, reasons for design decisions, block diagrams, SPICE modeling of the amplifier, schematic, and a complete parts list (almost all DigiKey part numbers).

16) FULL SOURCE CODE FOR THE TWO PICs IS SUPPLIED! This allows the builder to completely understand how it works and to modify the operation to suit individual preferences.

Kit Options:

Three options are being offered:

    1) Full kit - $195 plus $5 s/h

    2) Bare board set (no parts - boards only) - $25 plus $2.50 s/h ($5 via Priority Mail)

    2) Pre-programmed PICs (pair) - $25 plus $2.50 s/h ($5 via Priority Mail)

Please note that full kit includes the PC boards, printed manual, parts for the boards including pre-programed PIC's, pre-mounted AD9854 chip, and a very high quality Clarostat optical (not mechanical) encoder.

The IQPro kits are being handled by Bill Kelsey, N8ET, at Kanga US (www.kangaus.com)

Pictures, Block Diagrams and Schematics:

    IQPro running

    IQPro main board

    Block Diagram of IQPro

    Block Diagram of IQPro in Receiver

    Block Diagram of IQPro in CW Transmitter

    Block Diagram of IQPro in SSB Transmitter

    IQPro Schematic (page 1 of 2)

    IQPro Schematic (page 2 of 2)

    IQPro Operations Manual (PDF format)

    IQPro PIC microcode

Hint: Save the schematics on your hard drive and then open them with a picture viewer to see details.

Multi-band LNA/LPF Board for IQPro (NEW!)

    WHAT IS IT? Multi-band LNA-LPF Explained

    Multi-band LNA-LPF Schematic

    Multi-band LNA-LPF Board Picture

    Multi-band LNA-LPF Parts List (Excel Format)

IQPro Performance Reports / Measurements

    IQPro Phase Noise Measurements (Rev-1 8/5/2006) - by Gary Johnson, WB9JPS

    Wes Hayward, W7ZOI, comments regarding WB9JPS analysis of IQPro

IQPro User Pages

    WB9JPS - Gary Johnson (8/7/2006)

    W6JL - Don Huff (1/11/2007)

    K5EMI - Bill Stewart (5/27/2007)

    KA8RIZ - Steve Geary (3/25/2007)

    KD5BYB - Ben Hall (2/24/2007)

    G3UGR - Clem Tabor (3/4/2007)

    AB7O - Wayne Thurston (6/12/2007)

    AA3SJ - Ed Kessler (link to Ed's page 3/24/2007)

    WB9JPS - Gary Johnson (link to Gary's page 11/12/2007)

Support

See my YAHOO Group: DDS-VFO  for Support / Discussion / Files / Pictures / Documentation

Subscribe to dds-vfo
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PIC-EL Version 2   

A PIC Prgramming/Demonstration board for the

PIC ELMER 160 PROJECT

By Craig Johnson, AAØZZ

See my article about the PIC-EL in May, June 2007 QST magazines above

(See details on how this project originated below)

Download Page

PIC-EL II Features:

  PIC Programmer for 18-pin PICs via PC Serial Port

  Test your PIC program with these hardware components:

        - 2x16 line LCD (with backlight)

        - Rotary encoder

        - Three general purpose pushbuttons

        - Three LEDs

        - Speaker with driver

        - Stereo jack for paddle input

        - Stereo jack with transistor driver to key a transmitter

        - Transistor conditioner for converting low-level signals for PIC input (counter) detection

  16F628 PIC - preprogrammed with PIC-EL diagnostics - included   (source code available)

  Use with PIC Programming lessons - www.amqrp.org/elmer160/

  Adapter kit for programming 40-pin PICs (16F877) also available.   (NOTE: The PIC in the adapter does NOT operate the PIC-EL hardware.)

Kit Options:

Full kit: $55     ($60 with ZIF socket)
Bare Board: $20

16F877 Programming Adapter Kit: $15
(Requires ZIF socket on PIC-EL board)

PIC swap offer (by AA0ZZ)     6/16/2007

PIC-EL II kits are being handled by Bill Kelsey, N8ET, at Kanga US (www.kangaus.com)

Documentation and Schematic:

    Latest PIC-EL II Manual

    PIC-EL II schematic

    PIC-EL II - 16F628 Diagnostic - Source code

    PIC-EL II - 16F628 Diagnostic - Hex code

    PIC-EL II Flyer

    16F877 Adapter Instructions

    PIC-EL II Board vB4 Minor Rework Instructions

Hint: Save the schematic on your hard drive and then open it with a picture viewer to see details.

PIC-EL II Application Software (PIC 16F628)

    1) CW Keyer (K8-PE-V4) Source Code    HEX Code    Documentation

    2) DDS Signal Generator (PICELgen 6.0b) Source Code    HEX Code

    3) Frequency Counter (PECntr 2.7) Source Code    HEX Code    Calculations

Questions?

See my YAHOO Group: PIC-EL  for Support / Discussion / Files / Pictures / Documentation

Subscribe to pic-el
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Join us there and ask questions! Or E-mail me. (Address below.)

Start of "Retired" kits/projects

IQ-VFO

A 0-30 MHz VFO Using an AD9854 Direct Digital Synthesizer

Designed by Craig, AAØZZ and Bruce, AAØED

See my YAHOO Group: DDS-VFO  for Support / Discussion / Files / Pictures / Documentation

Complete Manual: Manual Ver 1.0f  (in PDF format)  Updated 01/31/05

Schematic: Page 1 of 2   (drawn with CircuitMaker)

                    Page 2 of 2

PIC16F877 Symbolics v5.19b     HEX    (Main Control)

PIC16F628 Symbolics v1.1c     HEX    (Encoder)

Parts List (updated 11/13/2004 - with prices)

Perfect quadrature output!   (0 - 30 MHz)

Performance Analysis  (PDF) New 01/31/05

Don Huff, W6JL, uses a HFVFO prototype with R2Pro

PowerPoint slides from my FDIM Presentation on May 15, 2003

Sorry, but the IQ-VFO kits are sold out and no longer available from AmQRP.

The "next generation", called the IQPro, is NOW AVAILABLE from Kanga. (www.kangaus.com).   See description above.

PIC ELMER 160 PROJECT

What is the PIC Elmer 160 Project? See: ELMER 160 Home Page

My contribution to the project -- to design the Programmer/Project board. (I call it the PIC-EL Board.)

Here's how it works!  PIC-EL Design Description

Pictures:

- My first conceptual schematic

- My first prototype (Manhattan style) - Getting the first bugs out. At least the programmer works.

- My second prototype - Now it's a signal generator (with my SIGGEN3+ code driving a DDS Daughtercard)

- 2-layer circuit board - The circuit board (created with WinBoard)

- Final Prototype - The final prototype

APPLICATION CODE FOR THE PIC-EL

    - PICELgen v1.4 source code- Signal Generator using PIC-EL and DDS-30 DDS Daughtercard

    - PICELgen v5.2 source code- Signal Generator using PIC-EL and DDS-30/DDS-60 DDS Daughtercard

    - K8-PE-Ver2-Keyer source code- K8 Keyer (16F84) for PIC-EL  (Original by Steven Elliott, K1EL)

    - K8-PE-Ver2-Keyer documentation- Documentation for K8 Keyer (16F84) for PIC-EL

    - K8-PE-Ver4-Keyer source code- K8 Keyer (16F628) for PIC-EL  (Original by Steven Elliott, K1EL)

    - K8-PE-Ver4-Keyer documentation- Documentation for K8 Keyer (16F628) for PIC-EL

PIC-EL (Rev A) Modifications

    - PIC-EL 16F628 Mods - PIC-EL (Rev A) modifications required to use a 16F628 PIC

My presentation at ATLANTICON 2004 (March 27, 2004)

    - The PIC-EL and Beyond - My paper for the Atlanticon Proceedings

    - PowerPoint Slides - My presentation

The PIC-EL Version 1 kits were only available from AmQRP for a short time. (Approximately 800 were sold.)

The "next generation", called the PIC-EL II, is NOW AVAILABLE from Kanga. (www.kangaus.com).   See description above.

2N2-40   (40 Meter transceiver - designed by Jim Kortge, K8IQY)

Design details at Jim Kortge's home page: K8IQY's 2N2 Homepage

Schematic   (drawn with CircuitMaker)

My 2N2-40 Layout   (PowerPoint format - to download and print - actual size)

SW-30+   (30 Meter transceiver - by Dave Benson, K1SWL)

Schematic in PDF format

My MH101 ("manhattan" style) version of the SW 30+    Picture 1   Picture 2

      - Pad layout in PowerPoint format (actual size): MH101 Pad Layout

      - All parts layout: All Parts

Next Project