Green Bay Professional Packet Radio

Green Bay Professional Packet Radio is our attempt at an advanced wireless communication research team.  Based in Green Bay, Wisconsin, we have banded together a small group of specialized residents who strive for the advancement of modern forms of electromagnetic wave communication.  We specialize in high-speed wireless data (packet), digital voice transmissions, ELINT/EW/ECM, radar, antenna design, bi-phase modulation and also the hardware/software side of all those types of communication.

We are die-hard radio homebrewers and experimenters.  While other people are drooling on nothing more than glorified ice cream truck 2-way radios, we are out using new and efficient modulation techniques and pioneering new developments in modern radio.  We've also homebrewed microwave radio bi-directional amplifiers for the local packet radio links, circular polarized repeater antennas, high quality audio hardware and all types of RF test equipment.

Modeled from the concepts originated by Clarence 'Kelly' Johnson (of Lockheed Martin Skunk Works fame), we attempt to push the boundaries of modern radio and antenna technology.  Using common off-the-shelf components, old VCRs, cellular phones, lots of trips to Radio Shack and, of course, well established theory.  We will always forge on.  Building and testing new designs while quietly ignoring anyone who tells us something is not possible.

Amateur Radio Projects

1. Low-Cost Wireless Network How-To
• Extremely detailed account of a Part 97 point-to-point 2.4 GHz wireless link.
2. Using Part 15 Wireless Ethernet Devices for Amateur Radio
• Hints, tips and rules for using off-the-shelf hardware for amateur radio Part 97 operations.
3. KB9MWR Projects Page
• Ongoing local amateur radio projects.
4. Mirror of the Guerrilla.net Website
• Mirror site of the Guerrilla.net L0pht spin-off project.  Few minor broken links.
5. Low-Cost POCSAG Paging Network How-To
• Homebrew your own amateur radio text or tone paging system.
6. Low-Cost Laser Data Links
• Quit shining laser pointers at people and use them for something useful.
7. Homebrew RF Design Test Equipment & Software
• Simple and useful tools for the RF experimenter.
8. Homebrew Bi-Directional 2.4 GHz Amplifier Designs
• Make your own amplifier for your 2.4 GHz wireless network.
9. Homebrew Bi-Directional 915 MHz Amplifier Designs
• Make your own high-power amplifier for your 900 MHz wireless network.
10. Homebrew 1 Watt 2.4 GHz Power Amplifier
• Increase the RF output power of your wireless network card to 1 Watt.
11. Homebrew 144 MHz to 2.4 GHz Transverter
• Scan and monitor the 2.4 GHz band using a common MMDS downconverter.
12. GBPPR Frequency Transverters for 2.4 GHz Wireless LAN Devices
• Change the frequency of your amateur radio 2.4 GHz network to overcome interference or line-of-sight issues.
13. Family Radio Service (FRS) to 900 MHz Transverter
• I was really bored.  (Unfinished)
14. GBPPR AutoFox
• Keys a transmitter and plays a pre-recorded message at one minute intervals.
15. GBPPR 2.4 GHz / 10 Mbit Wireless Data Link
• Why buy a wireless network card when you can tear your hair out trying to build one?
16. GBPPR POWER 64 kbps Wireless Serial Data Modem
• Experimental ideas for a low-speed, interference overcoming wireless data link.
17. GBPPR 900 MHz High-Speed Packet Radio
• Experimental ideas for a high-speed, interference overcoming wireless data link.
18. Elecraft EC1 Design Contest Entry
• It was a winner.
19. GBPPR 1 GHz RF Spectrum Analyzer
• Homebrew the most useful tool for a RF experimenter, work in progress.
20. Constructing Scotty Sprowls' 1 GHz RF Spectrum Analyzer
• This is a series of notes and videos on constructing the 1 GHz RF spectrum analyzer project by Scotty Sprowls.
21. Tracking Generator for a HP8569 Spectrum Analyzer
• Construction overview of a low-cost tracking generator for a HP8569-series spectrum analyzer.
22. Dataradio Gemini G3 UHF Radio Modem Experiments
• Information and experimental ideas for the Dataradio Gemini G3 UHF radio modem.
23. GBPPR 1 kHz to 16.384 MHz Synthesized Signal Generator
• Simple PLL signal generator for the test bench using a common Maxim IC.
24. GBPPR Divide-by-1000 3.5 GHz Prescaler
• Extend the frequency range on those cheap hamfest frequency counters.
• 13 GHz Frequency Counter Prescaler
25. GBPPR Packet Radio Weather Radio Alert
• Use the National Weather Service's alert tone to send a packet radio message.
26. GBPPR Portable Antenna Mast System
• Portable antenna mast system using PVC conduit.
27. GBPPR 900 MHz Frequency Hopping Spread Spectrum Transverter
• Frequency hopping transverter for amateur radio use.
28. GBPPR Portable 28 VDC Power Supply
• Simple and portable 28 Volt power supply.
29. GBPPR 1.2 GHz (23 cm) Amateur Video Transmitter
• Simple 1.2 GHz FM ATV exciter.
30. Converting Cellular Phones to 900 MHz
• Use old Motorola cellular phones as IF rigs in a 900 MHz transmitter.
31. Simple 2.4 GHz SWR Meter
• Simple way to tune wireless LAN antennas using an oscilloscope.
32. Linux FRS Radio Control
• Easily control a FRS/GMRS radio from a computer.
33. Return Loss Bridge for the Radio Amateur
• Device to quickly check the integrity of a radio antenna system.
34. Using the MC145158 PLL Frequency Synthesizer
• Simple overview and source code for the Motorola MC145158.
35. AeroComm CL4490 Experiments
• Wireless data networking experiments using AeroComm modules and data modems.
36. Metricom Ricochet Radio Experimentation
• Experiments using components from old Metricom 900 MHz and 2.4 GHz RF data modems.
37. 100 Watt RF Power Amplifier for 2 GHz
• Turn an old 1.9 GHz PCS cellular phone basestation into a RF power amplifier.
38. Qualcomm OmniTRACS Experiments
• Using Qualcomm OmniTRACS fleet tracking satellite systems for amateur radio applications.
39. General Electric GEMLINK Information
• Overview of a General Electric GEMLINK K-band video transmitter.
40. Motorola STF2520A 900 MHz Power Amplifier Modifications
• Modifying a surplus Motorola STF2520A cellular-band RF amplifier for 150 watts in the 900 MHz ham band.
41. 73 Magazine Information
• An attempt at a complete back issue and index listing for 73 Magazine.
42. Doodle Labs DL435-30 420-450 MHz OFDM Transceiver Experiments
• Experimenting with high-speec data in the 440 MHz ham band.
43. GBPPR VLF Converter
• Homebrew version Marty Kaiser's VLF59-10 5 to 500 kHz VLF converter.
44. HP4328A Milliohmmeter Overview & Probe Construction
• General overview of the HP4328A operation and how to make your own Kelvin bridge probes.

Other Projects

1. GBPPR Miscellaneous Projecmts      (Mirror)
• Other stuff you can blame us for.
2. GBPPR Homebrew Military & Espionage Electronics      (Mirror)
• Electronic projects for professional adventurers, independent contractors, and undocumented border patrol agents.
3. Brown County, Wisconsin Frequency Search
• Frequency search of local frequencies, PL-tones, DTMF codes, repeater offsets, notes, etc.
4. Green Bay / Brown County, Wisconsin 800 MHz Trunked Radio System Information
• Detailed information on the local public service trunked radio system.
• Illegal Activity by the Green Bay Police
5. GBPPR Microwave Oven & EMP Experiments      (Mirror)
• EME, remote power via RF, radar, landmine detection, HERF, EMP, etc.
6. GBPPR Homebrew Radar Experiments      (Mirror)
• FMCW/doppler & pulse-doppler types, battlefield & air surveillance using old parts from motion detectors and microwave ovens.
7. Passive Resonant Cavity & "Spycatcher" Technical Surveillance Devices
• Technical overview of the passive surveillance bug the Soviets used against the U.S. ambassador.
8. GBPPR 'Zine
• The monthly journal of the American hacker.
9. Low-Power FM Transmitter Circuits
• Help fight the liberal media.  Build a low-power FM or TV station.
10. Test Equipment Manuals
• Small collection of old test equipment operating and service manuals.
11. Obama FAIL!
• Helping to organizing communities to protect yourself from the Community Organizer.
12. GBPPR Parts Service
• Parts available for the experimenter for trade or swap.
13. GBPPR Vision
• Video series aimed at experimenters and hackers covering topics related to amateur radio, homebrew electronics, test equipment, etc.

Local Terrain & RF Plots

1. Elevation Plot for Green Bay, Wisconsin and the Surrounding Area
• Lowest elevation is 174 meters, highest is 274 meters.  Plot is 22.5 km square and the contour lines are at 10 meter intervals.
2. Zoomed Out Elevation Plot for Green Bay, Wisconsin and the Surrounding Area
• Lowest elevation is 176 meters, highest is 300 meters.  Plot is 50 km square and the contour lines are at 10 meter intervals.
3. Elevation Plot for the Northeast Wisconsin Area
• Lowest elevation is 176 meters, highest is 340 meters.  Plot is 100 km square and the contour lines are at 10 meter intervals.
4. Larger Elevation Plot for the Northeast Wisconsin Area
• Lowest elevation is 176 meters, highest is 579 meters.  Plot is 250 km square and the contour lines are at 10 meter intervals.

Interactive Wireless / RF Design Utilities

1. Wireless Network Link Analysis
• Calculates approximate received power levels and fade margins for microwave wireless links.
2. Wireless Network Link Analysis - Super Edition    (Mirror)
• Same as above, but generates a PDF file containing Fresnel zone and radio path graphs.
3. Microwave Radio Path Analysis    (Mirror)
• Generates a terrain profile graph and obstruction reports for a microwave radio link between two points.
4. Line-of-Sight Path Analysis    (Mirror)
• Generates a JPEG image showing the line-of-sight path for a given transmitter location.
5. Longley-Rice Path Loss Analysis    (Mirror)
• Generates a JPEG image showing the estimated Longley-Rice path loss for a given transmitter location.
6. Fresnel Zone Calculator    (Mirror)
• Calculates and graphs the required Fresnel zone clearances for a point-to-point link.
7. United States Elevation Retriever    (Mirror)
• Get the ground elevation at (almost) any location in the continental United States.
8. 3D Local Ground Elevation Map    (Mirror)
• Get a graphic 3D representation of the local ground elevations surrounding a transmitter site.
9. Parabolic Reflector Gain and Focal Point Calculator
• Calculates the gain, focal point, and radiation distances for parabolic dishes.
10. Urban Area Path Loss
• Calculates the approximate path loss through an urban area.
11. Antenna Up/Down Tilt Calculator
• Calculates the required antenna tilt to compensate for Earth curvature.
12. Distance & Bearing Calculator
• Calculates the distance and bearing between two geographic points.
13. Omnidirectional Antenna Beamwidth Analysis
• Estimates the coverage of a vertical antenna pattern.
14. Return Loss Calculator
• Calculates return loss given forward/reverse power or SWR.
15. Knife Edge Diffraction Loss Calculator
• Calculates knife edge obstruction attenuation.
16. Decibel Conversion Calculator
• Converts various values referenced to/from decibels.
17. Scattering Parameters Are Fun!
• Calculates gamma in/out from S-parameters, experimental.
18. Lumped Component Wilkinson Splitter / Combiner Designer
• Design Wilkinson splitters/combiners for use under 400 MHz.
19. Pi & Tee Network Resistive Attenuation Calculator
• Design resistive attenuators.
20. United States Frequency Allocations 30 - 3000 MHz
• Retrieve the FCC band allocation for any frequency.
21. Voltage To Power Conversion Calculator
• Convert AC voltages to power.
22. RF Safety Compliance Calculator
• Determines if your ERP will kill people.
23. Approximate Air Coil Inductance Calculator
• Calculates the approximate value of an air coil inductor.
24. Microstripline Analysis & Design
• Calculates the required width for making microstrip transmission lines.
25. Calculating Phase Line Length
• Calculates coaxial phase line lengths.
26. 3-Pole Butterworth Characteristic Bandpass Filter Calculator
• Designs simple 3-pole bandpass filters.
• Charles Toth has created an excellent Butterworth Filter Calculation Program for Windows.  (Help Files)
27. RF Pi Network Designer
• Designs Pi-type networks for transforming impedances.
28. PLL 3rd Order Passive Loop Filter Calculator
• Designs passive loop filters for phase lock loops.
29. Antenna Isolation Calculator
• Calculates isolation for horizontal & vertical antennas.
30. Mixer IMD Calculator
• Calculates potential IMD products in subtractive mode mixers.

• Perl CGI Sources for the Wireless Design Utilities: wireless.tar.gz
• Perl CGI Sources for the RF Design Utilities: rf_design.tar.gz
• Mirror website for the Wireless Design Utilities.

GBPPR Microwave Radio Path Analysis Tools

A Perl CGI program to graphically show the radio path profile between two points.  It will plot the 0.6 Fresnel zone and the true radio path for a given value of K (the effective Earth radius factor).  This is all displayed in reference to the path's elevation data taken at intervals along the link path.  This will let you see if you have a clear radio line-of-sight path.  Currently, the elevation data is only available for most of North America.  It is also extremely CPU intensive, so please be patient for the output PDF file to complete, or try again at a different time.

• Microwave Radio Path Analysis    (Mirror)
• Line-of-Sight Path Analysis    (Mirror)
• Longley-Rice Path Loss Analysis  (Mirror)
• 3D Local Ground Elevation Map  (Mirror)

All the plotting utilities are based around a slightly modified version of the SPLAT! program by KD2BD.

GBPPR Microwave Radio Path Analysis Tools  Source code for the above scripts.  (758k Gzipped TAR)

Advanced Wireless Communications Research Links

• AirHive Link Repository on Wireless, Mesh & Community Networks  Also, check out their videos
• High-Speed CSMA Digital Networking for HF
• The Utah T1-Rate Modem
• Optically Transparent Patch Antennas
• Weak Signal Communications, by K1JT (WSJT)  A software package designed for amateur weak-signal radio communication at VHF
• Microstrip Patch Rectenna With High Output Voltage
• Philips RF Semiconductor Application Notes
• High-Speed Networking Project
• Higher Speeds with the G3RUH 9600 Baud Packet Radio Modem
• The KD2BD 9600 Baud Modem
• 23cm High-Speed Link Receiver from F1BIU
• 23cm Wide-Band FM Data-Transceiver
• KE5FX's Homebrew 10 Mbit, 10 GHz Wireless Ethernet Project
• KE5FX Notes
• N6GN's Higher Speed Packet Web Pages
• DIY 10Mbps Optical Data Link
• DUAL - A Packet Format for a New Amateur Radio Link Layer
• The W1GHZ Online Microwave Antenna Book
• The PIN Diode Circuit Designers Handbook  (1.3M PDF)
• Papers by Hari Balakrishnan  Wireless TCP/IP god.
• Lucent Technologies Wireless Research Laboratory
• Antenna Visualization
• Electrical Engineering Training Series
• Online Lectures about Digital Communication
• XTP Overview  Alternative transport protocol.
• Time Domain  New ultra wideband modulation techniques.
• Communication Devices Using Ultra-Wideband, Nonsinusoidal Communication Technology  Cool stuff.
• Æther Wire Notes and Documents
• Ultra-Wideband Working Group
• UltRa Lab at USC
• Unofficial NEC Archive  Antenna modeling software.
• Decentralized Channel Management in Scalable Multihop Spread-Spectrum Packet Radio Networks  (780k PDF)
• A Channel Access Scheme for Large Dense Packet Radio Networks  (350k PDF)
• Design and Implemenation of a Wire Array Antenna Analyzer  (150k PDF)
• High Power, Broadband, Linear, Solid-State Amplifier Design
• SIGSALY Secure Digital Voice Communications in World War II
• Slot Antenna Design  by Stephen Bell, KB7TRZ
• A Transmission Line Calculator, Version 0.3  by Kevin Schmidt, W9CF
• Some Skin Effect Notes
• Tale of the Radioactive Boy Scout
• Lots of Good Weak Signal RF Links
• GNU Radio Project
• Temporary Telecommunications Infrastructure in Lower Manhattan
• SP-419 SETI: The Search for Extraterrestrial Intelligence
• Low-Cost, Long-Range Wireless Network How-To
• Low-Cost 2.4 GHz Digital Communications
• Chris's Wireless High-Speed Connect
• Another WAP11 Enclosure
• BAWUG - Outdoor Access Point Encloseure v1
• Notes on G-Lines (Goubau Transmission Lines)
• Free RF Schematics from Yordan Strundzhev
• Spread Spectrum - It's not Just for Breakfast Anymore!  by Harold E. Price, NK6K  (PDF)

Fractal Antennas / Fractal Geometry

If you think stringing wire between two trees is an antenna, you can skip this section.

• Fractal Antennas  by KB7QHC
• Fractal Antenna Systems
• Fractus
• The Koch Curve and its Variants
• Fractal Antennas
• Good Fractal Antenna Overviews by Peter Song
• Fractal Antenna Research at UCLA
• Fractal Tutorials
• What is a Fractal?
• What is a Fractal? #2
• What is a Fractal? #3
• Fractal World
• Fractal FAQ
• A Fractals Lesson for Elementary and Middle School Students
• Fractal Dimension
• Recursion and Making a Koch Snowflake with Maple
• Triangle Grid Paper  Print it out, and use it to make triangles.
• Sierpinski Fractal Triangle PostScript Code
• Introduction to the Mandelbrot Set

RF Design Notes & Links

• DatasheetDir  Really good datasheet directory listing.
• Datasheet Zone  One stop to find datasheets, IC pinouts, and application circuits.
• Circuit Sage  Excellent RF/analog circuit design website
• Greek Microwave Group  The Greek Microwave Group is a recently established group of telecommunication engineers and radio amateurs who are interested in the area of microwaves.
• Microsemi UM9601 PIN Diode Datasheet  (470k PDF)
• NEC UPG152TA GaAs MMIC SPDT RF Switch Datasheet  (26k PDF)
• Application of PIN Diodes  (258k PDF)
• Fast Switching PIN Diodes  (92k PDF)
• Applications for the HSMP-3890 Surface Mount Switching PIN Diode  (70k PDF)
• Intersil HFA3925 2.4 GHz Power Amplifier  Contains a good TX/RX switching idea (99k PDF)
• Mitsubishi Hybrid RF Power Amplifier Modules
• JavaScript Conjugate Match  by Nigel Martin
• Scattering Parameters
• Rob Frohne's Class Notes
• WA1RHP's Electronic Parts Inventory  Parts intended to support ham radio and electronic students
• Smith Chart Tools
• Microwave Group of San Diego Technical Articles and Projects
• American Technical Ceramics (ATC) Technical Notes
• Analog Computer Basics
• Radio Propagation Models
• General Soldering Information
• Desoldering THM and SMT
• Surface Mount Technology (SMT) Terminology
• Dielectric Constants of Commercial PCB Material
• Finesse Voltage Regulator Noise!
• Wavelet Resources from Mathsoft
• 2.4 GHz & 900 MHz Antenna Models
• Texas Instruments Technical Brief SWRA029 - Fractional / Integer-N PLL Basics  (6M PDF)
• Passive Repeaters in Wireless Data link Usage  From Microflect
• Utilizing Directional Antennas for Ad-Hoc Networking (UDAAN)
• VHF Narrowband FM Receiver Design Using the MC3362 and the MC3363 Dual Conversion Receivers  Motorola AN980 - Contains a good PLL loop filter overview for the MC14515x-series.  (630k PDF)
• Watkins-Johnson Company Tech Notes  Amazing technical notes from the 1970-1980s.
• Magnetic Properties of Ferrite Core Materials
• The Secret Life of Pots
• Hardware/Software Interface Description for PRISM Radio Design  Intersil Application Note AN9617  (70k PDF)
• PRISM1KIT-EVAL DSSS PC Card Wireless LAN Description  Intersil Application Note AN9624  (140k PDF)
• Processing Gain for DSSS Communication Systems and PRISM  Intersil Application Note AN9633  (32k PDF)
• Tutorial on Basic Link Budget Analysis  Intersil Application Note AN9804  (81k PDF)
• 2.4 GHz Direct Sequence Wireless LAN Cascade Analysis  Intersil Application Note AN9810  (71k PDF)
• Filters in the PRISM Radio Reference Design  Intersil Application Note AN9817  (80k PDF)
• A Condensed Review of Spread Spectrum Techniques for ISM Band Systems  Intersil Application Note AN9820  (164k PDF)
• Brief Tutorial on IEEE 802.11 Wireless LANs  Intersil Application Note AN9829  (72k PDF)
• HWB3163-EVAL PRISM II 11 Mbps PCMCIA Wireless LAN Evaluation Kit User's Guide  Intersil Application Note AN9864  (396k PDF)
• Obtaining the Best PRISM II Chip Set Receiver Sensitivity  Intersil Application Note AN9902  (23k PDF)
• Measurement of WLAN Receiver Sensitivity  Intersil Technical Bulletin TB382  (28k PDF)
• A Brief Tutorial on Spread Spectrum and Packet Radio  Intersil Technical Bulletin TB337  (58k PDF)
• Using the PRISM Chip Set for Timing Measurements  Intersil Technical Bulletin TB338  (20k PDF)
• XMIT_ID Version 2.61  Richard Rager's (KB8RLN), DOS program to "fingerprint" radios.
• Icom D-STAR ID-1 Evaluation  by KC0ARF, KB9MWR, KB9AMM, and N9PAV.  (Notes)
• Wisconsin Amateur Packet Radio Association
• MotoTRBO Out-of-Band Modification for 900 MHz Radios
• GaAsFET Pre-Amplifier Cookbook #3  by Kent Britain, WA5VJB  (2M PDF)
• MAX260 Filter Design Software  Microprocessor programmable filter design software (MS-DOS) for the Maxim MAX260/MAX261/MAX262.  (190k ZIP)
• MAX274 Filter Design Software  Filter design software (MS-DOS) for the Maxim MAX274.  (498k ZIP)

GBPPR - Facts Not Drivel

• Channel Capacity vs. Signal-to-Noise Ratio  (20k JPEG)
• A Discussion of Antenna Theory  by Paul Graham, K9ERG (One of the better antenna explainations out there)
• Maxwell's Equations  (18k GIF)
• PolyPhaser Technical Information  Trust these people
• Directive Gain, Salesmanship and Ham Radio!  How to determine the real gain of an antenna
• The Perils of Cheap Hamfest RF Adapters  More proof to avoid cheap hamfest connectors like the plague
• The UHF Type Connector Under Network Analysis  RF network analysis of a PL-259/SO-239 connection
• Electrochemical Potential Chart
• Conductivity and Dielectric Constants for Common Types of Earth  Parameters for use in Radio Mobile Deluxe
• Applying Modern Communication Technologies to Weak Signal Amateur Operations  Very good overview on using 1980's technology and math equations from 1948 to improve weak signal performance in the 21st century.  (657k PDF)
• Ufer Ground System  Grounding rods in concrete
• GBPPR Magazine Collection  In-print ham radio or electronics related magazine collection.  If you need an article scanned, just ask us.

GBPPR Technical Bulletins

• Waterproofing RF Connectors
• Advantages of Circular Polarized FM Repeater Antennas
• Why Silver Plate RF Components?
• How to Choose Inductors at RF
• Receiver Noise, Sensitivity and Dynamic Range Relationships
• Transmitter Site Rules
• How to Make RF Cables
• Nuclear Electromagnetic Pulse (NEMP) Survival
• Communication Channel Capacity

GBPPR Open Hardware License

• GBPPR Open Hardware License v1.0

FCC Compliance

Part 97.309 & 97.311 compliance specifiations and source codes to the programs used in our amateur radio networks.

Don't be stupid.

Passwords on all amateur radio nodes are either the user's callsign or disabled.

• gzip  Compresses and Decompresses Files
• mod_gzip  For Apache Web Servers
• OpenSSH  OpenSSH is used in compression mode only
• Brutalcopy  Pushes data using UDP protocol through rotten, overloaded and otherwise disgusting lines
• Vtun  The easiest way to create Virtual Tunnels over TCP/IP networks with traffic shaping, compression and encryption
• Amateur Radio ID'ing via ICMP Echo Request Packets  ID using ping packets and MAC manipulation.

Toward New Link-Layer Protocols for Amateur Packet Radio

• by Phil Karn, KA9Q
• Slides & Notes
• Take the Next Step with the Next Generation Protocol  by Naoto Shimazaki

Spread Spectrum Rule Recommendations

• by Phil Karn, KA9Q

Ideas for HF Modulation and Coding

• by Phil Karn, KA9Q

Proposed Coded AO-40 Telemetry Format

• by Phil Karn, KA9Q

Amateur Radio, Wireless Networks and the Information Age

• by Glenn Elmore, N6GN

Physical Layer Considerations in Building a High-Speed Amateur Radio Network

• by Glenn Elmore, N6GN

A Technological Rationale to Use Higher Wireless Frequencies

• by J.M. Vanderau, R.J. Matheson, and E.J. Haakinson  (1998 - U.S. Department of Commerence)

A Mathematical Theory of Communication

• by Claude E. Shannon  (1948)

An Overview of the Application of CDMA to Digital Cellular Systems and Personal Cellular Networks

• by Qualcomm  (1992)

A Method of Reducing Disturbances in Radio Signaling by a System of Frequency Modulation

• by Edwin H. Armstrong  (1936)

Shannon, Coding and the Radio Amateur

• by James R. Miller, G3RUH  (1995)

TAPR Packet Status Register Archives

• TAPR Packet Status Register Archives  Attempting to put all the TAPR Packet Status Register issues in one place.

The Shape of Bits to Come

• by James R. Miller, G3RUH  (1995)

Various TAPR Digital Communications Conference Speeches

• TAPR FHSS Radio Update - 2001  by John Ackermann, N8UR  (2.1M MP3)
• Spread Spectrum in the Amateur Radio Service: Current Status and Historical Notes  by Dewayne Hendricks, WA8DZP and Barry McLarnon, VE3JF  (3.5M MP3)
• Optimized Channel Access Mechanisms for Decentralized Spread Spectrum Packet Networks  by Matthew Ettus, N2MJI  (5.3M MP3)
• Status Report on TAPR 900 MHz Spread Spectrum Radio Project  by Tom McDermott, N5EG  (4.9M MP3)  (Slides)
• TAPR DCC '98: Introduction to Spread Spectrum  by Steve Bible, N7HPR  (YouTube)
• Infrastructureless Packet Radio Networks  by Don Lemke, WB9MJN  (Slides)  (YouTube)
• Introduction to Software Defined Radios  by Steve Bible, N7HPR  (10.7M MP3)  (Slides)
• TAPR DCC '97: Spread Spectrum Design and Theory  by Phil Karn, KA9Q  (Slides)  (YouTube)
• TAPR DCC '97: TAPR's 900 MHz Frequency Hopping Spread Spectrum Radio Project  by Tom McDermott, N5EG  (Slides)  (YouTube)
• TAPR DCC '97: Spread Spectrum Regulation and the Future of Ham Radio  by Dewayne Hendircks, WA8DZP  (Slides)  (YouTube)

Microwave Associates (M/A-Com) Gunnplexer Notes

• MA87127 Series 10 GHz Gunnplexer  Bulletin 7624A  (1M PDF)
• MA87728 Series 10 GHz Gunnplexer  (150k PDF)
• MA87729 Series 24 GHz Gunnplexer  (115k PDF)
• 10 GHz Ham Operation with the MA-87127 Gunnplexer  by Klaus Hirschelman, DJ7OO
• W2IOG Gunnplexer Notes  Simple FM radio modification
• The Gunnplexer Cookbook  by Robert M. Richardson, W4UCH.  (12.7M PDF)

10 GHz Path Loss Notes

1. Free Space Attenuation
2. Path Performance Calculations for 15 kHz IF Bandwidth
3. Distance vs. Carrier-to-Noise Ratio
4. Microwave Beams Behave Much Like Light Beams
5. Fresnel Zone Radius
6. K Factors
7. Surface Ducting
8. Elevated Duct

MMDS Downconverter Notes & Applications

• California Amplifier 31732 Information and Modifications  by Adam, G0ORY
• Gardiner MMDS Downconverter LO2398  by Adam, G0ORY
• California Amplifier 31732 Modifications for 2401 MHz Reception  by Ward, WC0Y
• California Amplifier MMDS Downconverter Partial Schematic  (97k PNG)
• Fujitsu FHX35LG Super Low-Noise HEMT  Pre-amplifier often used in California Amplifier downconverters.  (244k PDF)  (S-parameters)

Archived Down East Microwave Inc. Design & Library Notes

• Eliminate Low Frequency Intermod of LNA's  by Steve Kostro, N2CEI
• Intermod Resistant Preamplifiers  by Steve Kostro, N2CEI
• "My Pre-Amp Doesn't Work!"  A design, troubleshooting, and repair guide for all modern day low-noise amplifiers.  By Steve Kostro, N2CEI
• Building Enclosures for Microwave Circuits  by Rus Healy, NJ2L

Amateur Radio Repeater Notes

• Coaxial Resonators
• Articles by K7PP
• Homebrew Cavities and Duplexer
• The Repeater Builder's Technical Information Page
• SouthEast Iowa Technical Society
• 6 Meter Heliax Duplexers
• The KI7DX 6 Meter Repeater

Radar & Military Communications

Communication is the key to success.

• Electronic Warfare and Radar Systems Engineering Handbook  A must read
• Association of Old Crows Electronic Warfare Tutorial
• The Radar Pages
• Tactical Radio Jammers
• TRW Digital Processing and Antennas Boost Battlefield Capability of Milstar II Satellites
• Military Abbreviations & Acronyms
• Russian Electronic Warfare Equipment
• Electronic Warfare Programs by AN Nomenclature
• International Electronic Countermeasures Handbook
• EW Reference & Source Guide
• Rockwell Collins Defense Electronics
• Raytheon Defense Electronics
• Principles of the Meteorological Doppler Radar  Good overview of radar operations
• WSR-88D Technical Information
• WSR-88D Technical Information from Lockheed Martin  (250k PDF)
• WSR-88D System Specifications  (823k PDF)
• National Weather Service WSR-88D Transmit/Receive Status
• ITU Radar Bands
• Traffic Radar Handbook
• AN/TRC-170(V)2 Tropospheric Scatter Microwave Radio Terminal
• How to Use APRS for Direction Finding
• Doppler Direction Finder Design Notes
• Doppler Direction Finder Design Notes #2
• Epsilon Nought  Radar remote sensing
• MX Missile Command, Control & Communication  (850k PDF)

Hardware & Parts Suppliers

• Online Cables  Custom and pre-made RF cables at low prices.
• Coilcraft  Free sample inductors.
• Maxim IC  Free sample RF and analog ICs.
• Rogers Corporation  Free sample Teflon PC board.
• RF Micro Devices  Best assortment of RF ICs.
• Hittite Microwave Corporation  Sells RF ICs and evaluation boards directly to the public.
• Dan's Small Parts and Kits  Low-cost parts for the homebrewer.
• Down East Microwave  New & surplus RF parts/kits for the experimenter.
• Fair Radio  New & surplus RF parts and military surplus.
• FindChips.com  Fastest, most complete distributor search available.
• Radio Works  Ham radio supplies and RF connectors.
• Cable X-perts  Coax & RF connectors.
• The Toroid King  Best source for ferrite and powered-iron torroids from Dieter Gentzow, W8DIZ.
• Mendelson Electronics  Good surplus electronics deals.
• Richardson Electronics  Sells many hard-to-find RF parts in single quantities.
• INSTOCK Wireless Components  RF/microwave power dividers and power combiners for all wireless-band frequencies from 0.7-2.7 GHz.
• Radiodan  New and used Bird wattmeters and slugs.
• AIR802  Manufacturer of WiFi antennas, cable and connectors.
• PartSelect  Source of parts for repairing and modifying appliance and consumer electronics.
• Oems Cart  Search engine for electronic parts.

GBPPR Contact Information

• Will be back soon. Thanks to all supporters!
• Email #1:  contact [at] gbppr.org
• Email #2:  gbppr1 [at] gmail.com
• PGP Public Key
• Twitter:  GBPPR Twitter
• Facebook:  N9ZIA Facebook
• YouTube:  GBPPR YouTube Channel
• TruTube:  GBPPR TruTube Channel
• Bitcoin:  1EtFEY5Rq9NJLcEG7bvB8AsfYiaSvQMo4

List of website Recent Changes.

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The mailing list covers wireless networking, homebrew electronic projects, amateur radio projects, scanning radio projects, antennas, computers and everything else covered on this website.

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