DIRTY DISHES
and clean signals
the publication of The 50 MHz and UP Group of Northern California.
Now officially The 50MHz and Up Group of Northern California, Inc.


Volume 3 Number 2                  February 1998 (by Jeffrey Pawlan, WA6KBL)



Next Meeting, SUNDAY, Feb. 1st, 1PM sharp at Lockheed Bldg. 202.
PROGRAM:  The final call for nominations and the elections must take place between 1pm and 1:30pm as I must leave at 1:30pm. Please come before 1pm so that we can start on time! After the election, there will be a discussion of changing the meeting dates and also suggestions for Group projects and activities.

DIRECTIONS: The meeting place will be the Lockheed Auditorium in bldg. 202 on Hanover St. in Palo Alto, California. Access Hanover from Page Mill Road (between 280 and El Camino). Follow Hanover as it curves right and up the hill. Watch for the Lockheed sign indicating Bldg. 202 on the left side, about 2/3 of the way up the hill.

Officers until Feb. 1st
 
President  Jeffrey Pawlan  WA6KBL  408-371-0256  jpawlan@pawlan.com 
Vice President  Bill Rausch  AA6PA  408-637-0622  billraus@ix.netcom.com 
Treasurer  Will Jensby  W0EOM  408-296-6071  w0eom@aol.com 
Secretary  Bill Ogilvie  KQ6FY   415-968-3707  wogilvie@best.com 
Board Member  Art Lange  W6RXQ  408-735-1594   art_lange@trimble.com  
Board Member  Jim Moss  N9JIM  408-746-2789  jmoss@rockie.nsc.com 


Contests and Events
21 Feb 98    The Naval Postgraduate School ARC is having its 7th Winterfest on Feb. 21, 1998, in Monterey. Visit http://www.mcktech.com/wf98.htm website for details. It's a free public service event with the flea market paying for the event. Contact Doug McKinney at KC3RL@mcktech.com, or phone at (H) (408) 663-6117 in Prunedale, CA.

The first Foothill swapmeet of the year will return on Sat. Mar. 14

3-4 Apr 98   Southeastern VHF Conference, Atlanta, GA http://www.akorn.net/~ae6e/svhfs

Livermore Swap Meet - 1st Sunday of each month at Las Positas College in Livermore, CA, 7:00 AM to noon, all year. Talk in 147.045 from west, 145.35 from the east. Contact Noel Anklam, KC6QZK, (510) 447- 3857 eves.

VHF+ WeakSignal NETS
 
Sunday  8PM  144.240  Southern California WSWSS 
Sunday  8PM  144.250  Central California WSWSS 
Sunday  8:30PM  432.100  Central California WSWSS 
Tuesday  8PM  144.250  Northern California SWOT 
Tuesday  8PM  144.200  Arizona WSWSS 
Wednesday  8PM  144.240  Southern California WSWSS SWAP 
Thursday  8PM  144.250  Northern California SWOT SWAP 
Thursday  8PM  432.120  SCAL General, Oceanside, DM13 



50 MHz & Up Group Minutes

The 50 MHz & Up Group held their January meeting at the Lockheed-Martin auditorium on Jan. 11, 1998. Group executives and directors present were: Jeffrey Pawlan, WA6KBL, President; Bill Rausch, AA6PA, Vice President; Bill Ogilvie, KQ6FY, Secretary; Will Jensby, W0EOM, Treasurer; and Art Lange, W6RXQ, director. There were 16 members and visitors in attendance. The meeting began with a talk by Lou Dietz, formerly with Trimble, on the technical details of an Inmarsat transceiver.

The first item on the agenda was a discussion of progress to date on incorporation of the 50 MHz and Up Group for tax exempt status. All of the paperwork for the State of California had been completed and would be hand carried to Sacramento. There have been some changes to the Bylaws so that all of the legal requirements for a non-profit, tax exempt corporation can be met. At the close of the meeting, the incorporation documents were examined by all the Group officers and received all the required signatures.

An effort will be undertaken to establish a Group station, for EME activities. It is anticipated that this facility will be remotely controlled (except for contests) and will be available to all licensed members.

A vote of the membership unanimously approved the lowering of the dues to $15.00 a year, or $25.00 for two years. Nominations were opened for Group officers and directors. Will Jensby, W0EOM, was nominated for Treasurer; Bill Ogilvie, KQ6FY, was nominated for Secretary; Jeffrey Pawlan, WA6KBL, and Rex Allers, KK6MK, were nominated as directors. Nominations will continue during the February meeting, along with the elections.

de KQ6FY, Bill Ogilvie



Dues reduced to $15/yr and are payable now
The vote was unanimous to reduce the dues back to $15.00 per year. It was also decided that a special rate of $25 for two years be implemented. So far, only 20 people have sent or given the Treasurer their dues. Most of these were for two years at the special rate.


Non-profit Incorporation and Exemption from State Tax is Done!

It took more than two weeks of working at the Bylaws and Incorporation paperwork and also took two roundtrip drives to Sacramento. We now have official status as a California Non-profit corporation and Calif. tax exemption. I have also finished the paperwork for the IRS for 501c(3) Federal status. This was mailed on Jan. 22 to the IRS and may take up to 2 months, but hopefully less.

Photo of the finished incorporation filing and review in Sacramento

 

de Jeffrey, WA6KBL photo by Rex Allers, KK6MK


Presidentís Message
 
We have been in existence for 2 years now and I will be stepping down as President. I feel a sense of fulfillment from seeing the vision that I had take real form. This group of VHF/UHF and microwave radio amateurs is probably the finest in the country. We have real talent and expertise that will contribute to scientific knowledge and to the welfare of Northern California. The resourcefulness of our members and some non-members has turned some of the once empty microwave bands into crowded spectrum. The discarded broken and abandoned used materials, a.k.a. "junk", from local industry have been repaired, reworked, and often seriously modified to become parts of ingenious amateur communications systems. Other hams experiment with new circuit design from scratch, often finding very inexpensive solutions to otherwise difficult and costly problems.

Per the announcement in this Newsletter, we have obtained non-profit incorporation status from California and are waiting for our 501c(3) IRS determination. This will enable us to ask companies to directly donate their "junk" and decommissioned equipment rather than selling it to surplus dealers who then take a huge markup before we can buy it. Who knows, perhaps companies like H-P, Wiltron, EIP and others in our area might even find some second-hand or obsolete versions of otherwise working test equipment to donate to us.

The response in our survey that was mailed with the last Newsletter indicated that the idea of a remotely controlled Group operated microwave EME station was enthusiastically received. I would like to help design and build a state-of-the-art system that combines super quality RF stages with digital signal processing at baseband to provide audio and data communications via the moon in addition to standard cw. The antenna can be driven with interchangeable feeds and RF systems so that we can operate on several bands. This presents the opportunity to optimize the feed design for each band. I have been in contact with a scientist at JPL who has specialized in a technique to measure the surface defects in the large dishes. This technique, called Microwave Holography, is very exciting and I believe that we can do it. The scientist at JPL has agreed to process our raw data for us and produce images. I will print an excerpt of one of his articles from their website later in this Newsletter.

The 50MHz and Up Group will be having its election during the beginning of the Feb. 1st meeting. It is essential that you are there and vote if we are to survive. We especially need candidates for President and Vice-President as both positions will be vacant. The current Secretary and Treasurer have agreed to run for re-election but they do not need to run unopposed. Several people have agreed to run for a Board Member position. The Group has agreed to present a public technical conference in January 1999. We will need leadership to make this a success.

There are several very experienced engineers who are, or were, active hams. Some of these people have a great deal to teach others and should come out of hiding and join our Group and participate. Some of the surveys asked for more technical help and specifically for lectures by Bob Magnani, Bill Troechel, and Glenn Elmore. Bob Sutherland Sr., Ron Hopkins, Dave Leeson, Bruce Erickson, Mike Staal, and Steve Mieth should be contacted by members and persuaded to talk.

Several people have inquired whether we could build equipment at a meeting. If we were to have the meeting at a home lab where there is sufficient room, and if the people signed releases for liability, I think this is possible and encourage the next President and Vice-President to consider this.

I have read the surveys that have been returned and found that there were the same number of respondents asking for meetings to be moved to a weekday evening as there were who preferred Sunday meetings. Those that preferred Sundays often asked for the meeting to be moved to a Sunday other than the 1st one of the month. The number of respondents was too small to be representative of the Group as a whole.

There are more than 110 known VHF/UHF/microwave hams in Northern California on our list. Of these, only 20 so far have paid the dues for 1998. Get your dues in; come to the Feb. 1st meeting for at least ½ hour to vote; and call your friends. If you are one of those people who would prefer that the meeting day be changed, ask for it during the meeting. Remember, only votes at the meetings will make the difference, so if you donít show up, there will never be a change.

de Jeffrey, WA6KBL



A New U.S. 78 GHz Record

After about one year of preparation, AA6IW Lars Karlsson and W0EOM Will Jensby, made their first formal contact on 78.000 GHz at 2 PM on Nov. 28, 1997. W0EOM was located at the QTH of AA6IW and AA6IW was at the Stanford Radio Group, approximately 4.6 Km apart. With Lars was NV6KVG, Bob Johnson, who also has a 47/78 GHz rig using a harmonic multiplier as both transmitter and receiving
mixer. (Another Story). Margins were over 10 dB at both ends, so Lars and Bob Proceeded to move to the Canada College parking lot, which has a good view of the Bay area from NE to South. Lars was heard by Will soon after setup, but Lars' receiver failed so no two-way contact was made. Bob was not heard by Will, so the record was not extended.

On Dec. 11, 1997, a very clear, sunny day, temp. 70 degrees, F., W0EOM and KV6NVG proceeded to set up at Canada College, while AA6IW set up at his QTH. Also present was Jeffrey, WA6KBL, who witnessed this record event. Rifle scopes were used to boresite the antennas, and a two-way contact of 12.7 Km was soon completed. CW was used to exchange information, along with 440 Fm simplex as liaison. Signals were about 5 dB above the noise floor. Mirrors used to reflect the sunlight were also an aid in pointing. Bob was also able to hear Lars, but having about 15 dB less power than Will was not
heard by Lars.
 
Lars and Will both use independent transmit and receive chains. Turning on both allows the receiver to be zerobeat to the Xmtr. There is no danger of burning out the mixer with one milliwatt of power.
AA6IW's rig:
Antenna - 18" cast reflector using cassegrain sub-reflector.
Xmtr - X2 harmonic multiplier, about 2 milliwatts output, driver chain locked to rubidium standard.
Receiver - Harmonic mixer to 435 MHz all-mode transceiver. Receive L.O. is also locked to rubidium standard.
 
W0EOM's Rig:
12" cast reflector using polished dime as splash-plate feed (to be improved before next try).
Xmtr - X3 harmonic multiplier built by DB6NT.
Power output is - 3dBm at 78.000, plus 2dBm at 76 GHz.
Driver at 78GHz / 3 is about +17dBm.
The driver chain is locked to a Vectron model 71BY2828 10mhz standard. This is a miniature unit with very good stability and repeatability. Warm-up time is about 15 min.
Receiver - X2 Harmonic mixer using a DB6NT mixer board modified for waveguide input from an Avantek x2 doubler, 19.390 to 38.78 GHz, providing a 440 MHz IF to an R-7000 receiver. The L.O. is a 19GHz DMC phase-locked DRO. An oven was added for the crystal in the DRO, but it takes almost an hour before drift becomes tolerable. Another approach is planned, along with an upgrade to an 18" cast reflector with subreflector and an improved mixer.



JPL Article on:  Microwave Holographic Images of the Beam-Waveguide Antenna at the Venus Research and Development Site     click here:  http://heidi.jpl.nasa.gov/djr/holography.html

Tee Shirts

The members at the January meeting approved the logo designed by Rex Allers. It is now time to find out how many of which styles of shirts we want to order. The cost will depend on the style and quantity and will probably be between $10 and $14. Please come to the Feb. 1st meeting and let the new officers know what you prefer. We will then get a quote.


Microwave and millimeter wave charts and tools

The Group may wish to purchase or to make charts and handy tools for measuring waveguide. Here is a chart and a tool that Hughes made many years ago:

This is enlarged. It was made of very thin plastic and was very fragile. We could make it of heavier plastic or of metal.

Rex Allers made a lucite tool with only the larger sizes of WR90, WR75, WR62. We could do this as well.


DB6NT / Kuhne Electric finished products available now

If you want to get on any microwave band from 1296MHz all the way up to 121GHz but feel either queasy about construction at these frequencies or are just plain in a hurry, you can order completely finished ready to use amplifiers, downconverters, transverters, and multipliers. You can also order boards. Here are some examples:

 
     24GHz LNA board                         10GHz power amplifiers

Prices start at $200 and are around $350 - $500 for transverters. 10 watt power amplifiers at 10GHz are over $1000.

You can view many of these at the DB6NT webpage provided by Eric Bertrem in France: http://web.aurecvideo.fr/infracom/indexg.html Note that this is not a typo; this is really his address. It is not always up, however so try during the week and during the European daytime.

They can be ordered from Eric by email at infracom@avo.net or from Gerry Rodski (K3MKZ) at SSB Electronics (717) 868-5643 in Pennsylvania between 6:30pm and 9:30pm EST.



Free transmission line calculator

This program does microstrip, coplanar waveguide, and other planar transmission line synthesis for you. It is absolutely free. You will need to download it from the internet at http://www.appwave.com/page14.html Click on TXLINE.ZIP After you unzip it in its own sub-directory that you will probably name txline, you install it by running it. You will need to fill out a 4 page questionnaire and email that file to appwave. They then send you a registration number by email that permanently unlocks it.



Do you have a webpage relevant to our members? Let us know and we will put it here. (you must be a member)
 

ARRL Pacific Division Web page:  http://www.pdarrl.org/
Ham RF Exposure Guidelines Effective Jan. 1, 1998: http://www.arrl.org/news/rfsafety
Vanity Call Sign Gate 4 to Open Dec. 2, 1997

Rex's Place - KK6MK: http://www.dnai.com/~rexa/ Microwave stuff

Laser Communications Home Page! http://www.qsl.net/wb9ajz/laser/laser.htm Lots of bright stuff.