UTARC News
The Official Journal of the University of Texas Amateur Radio Club
April 1997
The Official Journal of the University of Texas Amateur Radio Club
April 1997
The March meeting of the University of Texas Amateur Radio Club will be held on Thursday, April 17 at 7:30 PM in RLM 5.120 on the UT campus. Talk in on the 147.18 MHz repeater.
Elections for the 1997-1998 school year will take place. The current officers are listed on the last page of this newsletter. Please consider accepting an officer position and helping the club to become more active and fun for all of the other members.
Last Meeting
Tim Baggett (AA5DF) gave a great presentation about Digital Signal Processing and Amateur Radio. The Kenwood TS-870, which uses DSP processing in the IF stage, demonstrated some amazing capabilities that cancel out noise and interfering signals.
Thanks to Roberto (KB2CLL) for providing the projection panel for viewing the Kenwood promotional video!
Joe Fisher (K5EJL) briefly spoke to the club about getting involved with other clubs in the Austin area for a combined Field Day effort. By combining efforts Austin area clubs hope to pool resources and create an event that will draw media attention.
Want to get a jump start on joining UTARC for the 1997-1998 school year? You can submit a membership application now and ensure that the club will maintain contact with you next September.
The following people have joined UTARC for the 1996-1997 year (and also 1997-1998):
Name CallsignMichael Evans Pending
Welcome aboard! To join UTARC get in touch with one of the club officers listed later.
de KM5FA
With the donation of a used VGA monitor to the club by Kevin Mandaville KG5KI, the club station now has a PC that can display high resolution color graphics. This enables us to run many more ham radio programs than before, including those running under Windows. One of the experiments I've been pursuing since the donation of the new monitor is attempting to get W5EHM capable of sending and receiving Slow Scan Television (SSTV) transmissions over the HF bands. This experiment has been partially successful.
The most common SSTV interface hardware for the PC is a circuit known commonly as the "Hamcomm Interface," a name that comes from the program Hamcomm program. The club's AEA PK-900 multi-mode data controller has a mode available on port 1 of the box called "analog" mode, that for most purposes does exactly the same thing to an incoming signal as the Hamcomm interface. In fact, after setting the PK-900 in analog mode, I have been able to use a program called JVFax to decode SSTV transmissions on 20M. JVFax is a freeware program that supports all the popular SSTV and facsimile transmission formats and allows you to save them in a variety of common graphics formats on your hard disk.
JVFax is also capable of transmitting graphics files over SSTV, but this is where the PK-900 interface falls a little short. Apparently, the PK-900's analog mode will not transmit until it sees the character 'x' and will not stop transmitting until it sees the character ctrl-D. This is consistent with how the PK-900 handles other HF digital modes, such as RTTY. At least I assume it will transmit, as the two commands will toggle the PTT line on the microphone connector, but the PK-900 manual actually says that transmission under analog mode is "not yet supported." In any event, I have been unable to find an easy way to get JVFax (or any other SSTV program) to prepend and append these control codes to a transmission sequence - the actual Hamcomm interface does not require them.
Further investigations will be made, including possibly writing to the JVFax author to see if there's a simple fix he could write into the program. Several graphics files are already prepared in the JVFax directory for transmit should the hurdles mentioned above be overcome.
de AB5N
The Survival Research Labs (SRL) performance during the weekend of March 29-30 was impressive indeed. I think it was the event of the decade in Austin!
Nothing really could compare with the sheer joules expended there. The sound out of the Ford V8 injected German V2 rocket engine was 150db. The twenty foot acyeteline cannon was being shot at the crowd and knocking people over. The three story Tesla coil's primary was primed with a 25kV 4 amp supply. The oil filled caps were over 1500lbs. The ram-jet go cart's engine glowed red hot as it sped around the track spinning out of control. It took a month to create the show, which included a 85 ft replica of the main building with a robotic Charles Whitman shooting at the crowd. Several VW sized robots fought it out using claw arms and flame throwers. There were piles of white plastic buckets filled with magnesium filings hidden inside displays. An entire cow was on a giant revolving arm, and was "cooked" by a V8 blasting raw gas through a nossle (50 ft. flames). In the end, everything burned to the ground.
It took years to arrange a performance space for this show. The problem is that the liability insurance is really high for SRL. To make things worse, SRL then called to say that they would need the equivalent of four ISDN lines of Net throughput for the show.
That's normally not a problem, but to get that in two weeks lead-time at a remote site was impossible.(Longhorn Speedway) SW Bell said they just didn't have the switching capability nearby the site, and even if they did, you can't get a "temporary" ISDN line dropped. There isn't even any phone service at the site. I got called from San Francisco by SRL to see what could be done with a microwave setup. I quickly made a list of possible donors of Wireless LAN modems. Of all the people on the list, the local Monster Bit group came across with a set of 2.4 GHz modems and 2.5ft. dish antennas.
The decision was made to use a dual ISDN drop that was at a guy's house across from the KLBJ AM towers on 973 just south of 969 (MLK). A dish was set up on a mast on the top of the grandstand at the raceway. A very large "Cherry Picker" was rented for the ISDN origination point. GPS's were used to determine the bearings between the two antennas.
The modems are 100mW and the dishes are over 20db gain. Cheap and lossy coax patch cables were supplied, but were used because of a proprietary RF connector on the modems. Also supplied were two runs of 9913 type coax. Although preliminary tests from a hill at the 969/973 intersection showed immediate and strong signal data "lock-up" ( a green light goes on in the modem), when the cherry picker was raised at the ISDN source, it was dead. It was two hours before the show and folks were starting to panic...but when I checked the signal path again, it was obvious that the dish at the house was only even with a ridge of trees along 71 near Bergstrom. That spring foliage just eats 2.4 GHz RF. I then got an idea. Cut out all the 9913 on both ends. 75 feet of 9913 at 2.4 GHz is a dummy load. I put the computer up in the cherry picker basket and cut off the strange brass crimp-on connector. I pitched the 9913 and used a small hose clamp to re-secure the braid on the crimp-on's collar. I re-set the dish's position...and just for a second, it locked up! Yes!
I then sped to the raceway, climbed the ladder to the top of the grandstand...people were making way for me..."Are you the Ham guy?-go go go". I did the same thing there. It was almost dark, and I had just a little fuel left in the butane soldering gun. I duct taped the dish in place and two seconds later, someone yelled "Its connecting!". The signal is read out on the screen...level and signal to noise ratio. We had 22% signal and 85% packet acquisition. That gave 90% of the two ISDN lines throughput. Well, needless to say I was a happy camper. The "Ham guy" was treated like royalty for the evening including a rousing applause from the SRL folks. There were scads of computer experts there, but dang if it didn't take some good old RF technology to connect them out to the world.
The purpose of the connection was to make the "event" available real-time on the net. The validity of that is questionable in my mind, but the fun of making a microwave SS data link work with a short deadline....that was definitely fun!
For learning more about Spread Spectrum Data communications, check the TAPR Web site. There you will find a book by Tom McDermott called "Wireless Digital Communications: Design and Theory". Its written exactly at the level a ham can digest, and when you read it, you will be reading the story of radio for the 21st. century.
de KM5FA
1996-1997 saw some significant changes an accomplishments in the University of Texas Amateur Radio Club. Many more projects and experiments will continue into the summer and beyond.
Equipment: The past year has seen a tremendous amount of work on the club's shack. Last April, the club installed a new Rohn tower, replacing the old tower that collapsed in September, 1995. The new tower includes a Force 12 C-4 20-15-10 tribander yagi, a 13-element 2m yagi, a 3-element 6m yagi (a donation from K5TR), and a 2m vertical antenna. Inside the shack, the club's computer system has been upgraded to an 80386DX with a VGA monitor, mouse, and more memory, thanks to donations from N5TR, KG5KI, and AB5N. AA6TY donated an AEA PK-900 multimode data controller to the club to replace our malfunctioning Kantronics KAM. Thanks to AA5BT, the remote VFO on the Kenwood TS-830S HF rig was finally brought back to service with repair to the TS-830S. Finally, a large Motorola FM radio that belongs to the club was "rescued" from the hallways of WRW by AB5N, who is now storing it in his office.
Contesting: W5EHM roared back into life during the 1996 November ARRL Sweepstakes. Scoring 103,500 points in the CW contest and 194,688 points and a "clean sweep" in the phone contest, the best club scores in five years. Additionally, the club earned a strong fourth place finish in the 1996 Collegiate Championships. W5EHM also became active for the first time in seven years in the VHF+ contests, winning the South Texas section in both the Western States Weak Signal Society VHF Sprint and the ARRL September VHF QSO Party.
Awards: In the last year, W5EHM earned both the VHF/UHF Century Club (VUCC) award for 50MHz, and Worked All States (WAS) on HF. W5EHM has also recently applied for 5-band Worked All Continents (WAC) award.
Activities: Bob AB5N, consulting engineer for KVRX and KVR9, gave club members a tour of both the 440MHZ and 1.2GHz repeater site on top of RLM and the KVRX/KOOP 3KW, all solid-state transmitter site in southeast Austin in November. Club members Kourt KB5PRZ and Robert KA5WSS provided communications support for the Austin Rowing Club's "Pumpkin Head" regatta this past fall.
Guest Speakers: UTARC meetings enjoyed the presence of several guest speakers this year. Greg Jones WD5IVD, president of Tucson Amateur Packet Radio (TAPR) spoke to the club in January about Spread Spectrum and TAPR's Special Temporary Authority from the FCC. Tim Baggett AA5DF discussed DSP applications and gave a live demonstration of a Kenwood TS-870, with a Motorola DSP built into the IF stages in March. Last October, George Fremin K5TR, winner of this past IARU HF Championships, spoke to the club about contesting. Ken Harker N1PVB spoke to the club about VHF Weak Signal DX work in November.
Reaching out: In January, UTARC club members voted to join TAPR and petition to be included in the TAPR spread spectrum STA. Last summer, W5EHM became a member station of the Six Meter International Radio Klub (SMIRK). In December, UTARC agreed to serve as host of the 1997 annual meeting of the Texas Packet Radio Society (TPRS) this coming December.
Continuing projects: As a participant station in the TAPR Spread Spectrum STA, club members voted to authorize the club officers to spend up to $500 to participate in a TAPR group purchase of Spread Spectrum radios. A group purchase planned for January fell through, and the current status of the group purchase is in limbo. George K5TR has managed to acquire an amplifier for the club that, after modification, should put 500 or more watts out when driven with the club's 6m radio. The club is also actively looking to become active on 432MHz SSB/CW. Robert KA5WSS has been working on building a second 80386 PC out of spare parts in order to run Linux 2.0 as a platform for spread spectrum networking experiments or other Amateur Radio digital networking projects that the club might decide to pursue.
DX'ing
Derek (AA5BT) reports that the club has received a QSL card for contact made with XZ1N (Burma, a.k.a. Myanmar).
George (K5TR) has been using the club's 30M dipole with great success in making QRP contacts with his homebrew rig.
Awards
Robert (KA5WSS) has gathered up the cards needed for the club to obtain a 5 band Worked All Continents (5BWAC) certificate.
Damage
The storm that blew through Austin on Friday, April 4 did not break any equipment. However it did cause the C-4 beam antenna to twist along its boom such that the elements are no longer horizontal to the ground.
Work To Be Done
If you would like to help with some of these items, contact one of the club officers.
Wish List
Do you have any of this type of equipment that you would like to donate to the club? Actually the club is willing to accept most any type of donation. We'll put it to good use and the donation can be tax deductible!
In addition to helping push up the club's DXCC count Kenneth (KM5FA) has been working toward DXCC himself. On Friday, April 4 Kenneth worked stations in ET (Ethiopia), TJ Cameroon and TU (Ivory Coast) to push his country count to 100. Congratulations Ken!
de WS1A from the Internet
DX station speaks in bold followed by the US DX'er translation. Don't operate this way!
The Whiskey-One something only, call again.
Everyone call again.
Is this frequency in use?
Thanks for holding the frequency for me. You can QSY now."
CQ Contest.
Unless you're from Wyoming or Nevada, don't call.
My power is 300W.
How do you like my new parallel Alphas?
Frequency is occupied!
Oh, there you are. We've been holding the frequency for you.
Please move [up/down] a little.
Oh, there you are. We've been holding the frequency for you.
QSL QRZ?
Bet you can't guess my call!
de ???
Here's an easy game to play.
Here's an easy thing to say:
If a packet hits a pocket on a socket on a port,
And the bus is interrupted as a very last resort,
And the address of the memory makes your floppy disk abort,
Then the socket packet pocket has an error to report!
If your cursor finds a menu item followed by a dash,
And the double-clicking icon puts your window in the trash,
And your data is corrupted 'cause the index doesn't hash,
Then your situation's hopeless, and your system's gonna crash!
You can't say this?
What a shame sir!
We'll find you
Another game sir.
If the label on the cable on the table at your house,
Says the network is connected to the button on your mouse,
But your packets want to tunnel on another protocol,
That's repeatedly rejected by the printer down the hall,
And your screen is all distorted by the side effects of gauss
So your icons in the window are as wavy as a souse,
Then you may as well reboot and go out with a bang,
'Cause as sure as I'm a poet, the sucker's gonna hang!
When the copy of your floppy's getting sloppy on the disk,
And the micro code instructions cause unnecessary risk
Then you have to flash your memory and you'll want to RAM your ROM.
Quickly turn off the computer and be sure to tell your mom!
"Computers in the future may weigh no more than 1.5 tons." --Popular Mechanics, forecasting the relentless march of science, 1949
"I think there is a world market for maybe five computers." --Thomas Watson, chairman of IBM, 1943
"I have traveled the length and breadth of this country and talked with the best people, and I can assure you that data processing is a fad that won't last out the year." --The editor in charge of business books for Prentice Hall, 1957
"But what ... is it good for?" --Engineer at the Advanced Computing Systems Division of IBM, 1968, commenting on the microchip.
"There is no reason anyone would want a computer in their home." --Ken Olson, president, chairman and founder of Digital Equipment Corp., 1977
"This 'telephone' has too many shortcomings to be seriously considered as a means of communication. The device is inherently of no value to us." --Western Union internal memo, 1876.
"The wireless music box has no imaginable commercial value. Who would pay for a message sent to nobody in particular?" --David Sarnoff's associates in response to his urgings for investment in the radio in the 1920s.
"The concept is interesting and well-formed, but in order to earn better than a 'C,' the idea must be feasible." --A Yale University management professor in response to Fred Smith's paper proposing reliable overnight delivery service. (Smith went on to found Federal Express Corp.)
President: Tom Orzechowski SQ9DDZVice President: Kenneth Harker KM5FA 467-8724 kharker@cs.utexas.edu
Secretary/Treasurer: Kourt de Haas KB5PRZ 445-4759 kourt@mail.utexas.edu
Newsletter Editor: Robert Barron KA5WSS 837-4051 barron@liant.com
UTARC Web Page URL: http://www.utexas.edu/students/utarc/
Mail Reflector: utarc-l@mcfeeley.cc.utexas.edu
UTARC News is published by the UT Amateur Radio Club, a registered student organization. UTARC News is not an official publication of The University of Texas at Austin and does not represent the views of The University or its officers. This newsletter was not printed with state-appropriated funds.
Newsletter Contributors: AA5BT, AB5N, KM5FA
Roaming on or near campus? Take your 2M radio with you and listen for other UTARC members on the 147.18 MHz repeater!
Got a project idea for the club? Let the officers know!
The University of Texas ARC
Box 170, Texas Union
Austin, TX 78713