Ham Radio 101 – How a Crystal Radio Works

How a Crystal Radio WorksFor many of us older guys, our first experience with home brew was building a crystal radio. Incredibly simple, yet also incredibly magical, some wire a paper tube and a piece of rock suddenly sent Tiger Baseball into our headphones.

From our friends at CrystalRadio.net, some accessible and fun radio theory in practice.

Jean Shepherd on Amateur Radio

ShepBroadcaster and raconteur Jean Shepherd, K2ORS was an avid amateur radio enthusiast. He spoke often of the hobby on his WOR broadcasts. With thanks to Joe Levine, W8JRK, here is a link to an archive. Included in the collection is his 1985 Dayton HamVention speech where a number of MSUARC members were in attendance.  It’s still as funny as it was back in 1985. And anyone who has been in the Armed Forces will surely appreciate “Code School”. Some fun listening.

Echolink Connectivity Returns to W8MSU

EchoLinkIconGood News !  Andrew Temme and I finished installing the new windows 7 computer up in the repeater cabinet this afternoon. After a bit of reconfiguring we were able to bring up Echolink and connect to both W8UM and another repeater in Dayton.  We may not have EVERYTHING configured properly, but it looks as though all of the main tone access functions are working.  So enjoy the use of the Echo Link System folks.  We’re back on line!  If any users out there encounter problems , please e-mail me to discuss it, it may just need a bit of TLC. (and a bit of reconfig)

A special word of thanks to the good people in DECS, who graciously helped us with both computers and software to revive our linked system. 73 Gregg WB8LZG

Minutes of the 3/19/15 MSUARC Meeting

Here are the meeting minutes for 3/19/15:

The meeting came to order at 7:05p.

Present were:  Scott KB8VWM, Forest  KD8NKI, Reece  KD8VNY, Teng (no license yet), Andrew  KE7ESD, Gregg  WB8LZG, Ed W8EO, Bob W8RSJ, Dennis  KB8ZQZ, Steve WB8WSF, John KD8BQX, Dave, K8GVK.

Reece accepted the role of Club President for the following academic year.  Teng and Scott are also willing to be on the Executive Board in other positions as needed.  Forrest said that he might be able to be on the Executive Board.  Nick was not present, but we can also ask him.

Steve recommended checking student directory names against the FCC database to identify licensed amateur radio operators, and to invite them to join the club.  The student leadership can decide if they want to try this, and the benefits and drawbacks of this approach.

We will want to be present at Sparticipation.

If we are able to get an advertisement into the student welcome packets, that could also help promote the club.

The Michigan QSO party is on Saturday 4/18 from noon-midnight.  The club will be participating in that contest.

Reece put together a wish list of computer equipment for the club shack.  Gregg said that he will filter down the list to the most essential items, and talk to his contacts among the university administration and alumni to try to make this happen.  Reece said that he specially chose the hardware for optimal software-designed radio performance.  A discussion ensued over how much computer performance was needed, and whether or not used computers could work.  John and Steve work with computers and suggested that they could obtain used computers relatively inexpensively.  Reece said that some SDR applications on his i7 quad core laptop struggle, so a faster computer may be needed for some possible club projects/applications.  Reece’s cost estimate for the high performance machines is around $3,000, with some variability depending on specific components used.

Setting up a regular meeting time was discussed.  This discussion was adjourned until the next club meeting, scheduled for Thursday 4/16 at 7:00p.

The 6 meter antenna on the mast is currently not being used much.  We discussed the pros and cons of taking down that antenna to free up mast space for another antenna.

Topics to discuss at the next meeting:  Open Shack Night, MSUARC website, Antennas.

The meeting ended at 8:30p.  Gregg had an informal post-meeting presentation about how to operate the Orion 2 radio and the antenna selector/tuner in the shack.

Scott KB8VWM

The Voice of Victory – 1944

A film about radio use at the end of the Second World War. There is an interesting simulation of an AM ham radio contact at 3:08.

Ham Radio 101 – Antenna Tuners

If you’ve ever sung in the shower and hit a note where the sound seemed to amplify, you’ve experienced resonance. Every antenna has a particular frequency on which it is “resonant”. When we transmit on a radio frequency that is resonant with the antenna, very little power is lost and you are efficiently sending the most energy over the airwaves. Resonance is typically measured as the Standing Wave Ratio or SWR.

In the world of RF, any time you connect a transmitter to a circuit that’s not resonant, power is reflected back from the antenna into the transmitter.  Worst case, this situation can damage your equipment, so you want to avoid a bad match at all costs.

Enter the antenna tuner. This is a device that uses capacitors and an inductor to match an antenna (or load) to a transmitter, even if the antenna is not resonant at the transmitted frequency.

Here’s a video that shows how to use an antenna tuner to create a good match with a minimal SWR.

MSUARC Meeting Tonight!

Join us March 19 at 7PM, 2121 Engineering Building for the MSU Amateur Radio Club March Meeting. We’ll review W8SH’s current equipment compliment and hold a maker-space build-it-yourself session on “Building an Audio Oscillator.”
See you there!

Amateur Radio Broadband

D-RatsCan radio amateurs connect their computers across a wireless network? You bet. Firing data between ham stations is as old as the Morse Code. With the advent of Packet Radio Two popular ways to do it are D-RATS and HSMM-MESH. D-RATS is a lot like what Internet Relay Chat used to be. In its current iteration it is primarily a tool for exchanging text message, one to one, or one to many. D-RATS was designed to take advantage of D-STAR‘s low speed data capabilities, but many hams are connecting to D-RATS servers over the Internet, using them to practice exchange of messages to prepare for disaster communications scenarios. There are a number of D-RATS devotees around, but the favored client software has not been updated in over two years.

High Speed Multimedia (HSMM) is the ham radio version of WiFi. Channels 1-6 in the WiFi spectrum fall within the amateur bands. If you have a Technician or higher license, you can operate under Part 97 of the FCC rules, using higher gain antennas and more power than typical WiFi access points use under Part 15.

Mesh Network DiagramThere is growing interest in using HSMM to create a Mesh Network, where wireless nodes are interconnected to exchange data at high speeds. The concept began as a solution for developing countries who don’t have robust wireline Internet connectivity. Installation of a number of Mesh Nodes in a neighborhood, with one linked to an Internet connection can provide access for everyone on the Mesh network.

Ubiquity M2 BullettIn the amateur radio world, it’s possible for hams to create an HSMM go-kit, containing several Mesh Nodes and create a fully functioning high speed data network at a disaster site. In communities where HSMM-Mesh has become popular, dozens of nodes may be in peer to peer communication with one another, and hams may connect servers to the network to provide special services. Connecting to the Internet can be one of these services, but if you do it, you are responsible for making sure that all content that flows to and from your node falls within the guidelines of Part 97.

BBHN, who formerly called their organization HSMM-MESH, will kick-off a new project this weekend, focused on taking this technology to the next level. Comprised of the project manager, developers, and several of the testers who brought BBHN to the Ubiquiti line of wifi hardware, this team is geared to pick up where BBHN leaves off.

The Amateur Radio Emergency Data Network, or AREDN (“r-den”) has been chartered to provide the Amateur Radio Community with a quality solution for supporting the needs of high speed data in the Amateur Radio Emergency Communications field.

You can download the latest AREDN software release (3.0.2) from their website to explore an EMCOMM mesh implementation in your community.

There are a growing number of HSMM-Mesh resources out there.My Rocky Mountain Ham buddies maintain an HSMM Yahoo group with information about the latest developments. And here’s a good place to start your exploration.

Why You Should Learn to Love Ham Radio

Icom IC71000

An appreciation by Jason Feifer in Popular Mechanics.

The latest flavor of the Raspberry Pi tastes really, really good.

The latest Raspberry Pi900MHz quad-core system-on-chip,  1GB of RAM, and still just $35.00. I use the Pi to interface with my D-Star DVAP dongle and it’s been darn near bulletproof. Eager to put this baby through her paces.  Here’s more from Gizmodo.