W6IFE Newsletter

President Doug Millar,
K6JEY 2791 Cedar Ave Long Beach, CA 90806
562-424-3737 [email-masked]

VP Dave Glawson,
WA6CGR 23437 E Amberwick Pl Diamond Bar CA 91765
909-861-7036 [email-masked]

Recording Sec Mel Swanberg,
WA6JBD 231 E Alessandro Blvd Riverside, CA 92508
909-369-6515 [email-masked]

Corresponding Sec Kurt
Geitner, K6RRA 1077 E Pacific Coast Highway #142
Seal Beach, CA 90740 310-710-7810 [email-masked]

Treasurer Dick Kolbly,
K6HIJ 26335 Community Barstow, CA 92311
760-253-2477 [email-masked]

Editor Bill Burns,
WA6QYR 247 Rebel Rd Ridgecrest, CA 93555
760-375-8566 [email-masked]

Webmaster Chip Angle, N6CA 25309 Andreo Lomita, CA 90717
310-539-5395 [email-masked]

ARRL Interface Frank Kelly, WB6CWN 1111 Rancho Conejo
Blvd. #501 Newbury Park, CA 91320 805-499-8047 [email-masked]

W6IFE License Trustee Ed Munn, W6OYJ 6255 Radcliffe Dr.
San Diego, CA 92122 619-453-4563 [email-masked]

At the 6 March 2003 meeting of the SBMS
Chuck, WA6EXV
will talk about the construction and operation of the 1296 MHz to 2304 MHz
translator and beacon which was installed on Heaps Peak, DM14kf in November.
Nominations will be asked for from the floor prior to the April election of
officers for the 2003-4 period. The SBMS meets at the American Legion Hall 1024
Main Street (south of the 91 freeway) in Corona, CA at 1900 hours local time on
the first Thursday of each month. Check out the SBMS web site at
http://www.ham-radio.com/sbms/.

Last meeting had Doug, K6JEY talk about the
HP-Z3801A GPS receiver and its various revisions along with the software to
allow you to control it. Doug had a handout on the various software available to
work with GPS machines. Thanks Doug. Welcome to visitor Howard Bogen, WA6YGB of
Pasadena and to Bill Davis, K0AWU of Grand Rapids, MN. Welcome to new members
Bill Honeyman, KG6CNL of Huntington Beach; Steve Unger, AD6XQ of San Diego; and
Wayne Yoshida, KH6WZ of Huntington Beach. Welcome. Chuck Swedblom, WA6EXV was
presented with a Life Time Achievement Award from SBMS for his outstanding work
in creating new technology applications for microwave use. Ken, WB6DTA had power
supply kits for the 24 GHz Pcom rigs available. The 2 GHz and up contest was
discussed. Reports from the ARRL 10 GHz contest were discussed as found on the
ARRL web site and in QST. It was nice that a large number of SBMS members
reported their activity from the contest. Chip, N6CA brought us the sad news
that Gary Belda, K6ENS had passed away. It was reported that the Clint, W1LP
ship had been sold to another group and had been scraped. 32 people present.

Pres Sez- Congratulations to those in the 10 GHz
and Up contest. The number of log entries was fantastic. I suspect plans are in
the works for better scores next year. I've been following with interest the
developments on the millimeter wave and up bands done by hams in this and other
parts of the country. Kerry, N6IZW and Chuck, WB6IGP have been working on
coherent light communicators for several years now. Over time their experiments
have produced slow and steady progress.

I'm sure others have had dreams about making equipment for higher bands but
felt frustrated by either equipment or cost. I have some suggestions based upon
what I have seen others do. First is to find a partner that will be someone to
talk to and help with equipment or construction. Then pick a band or work your
way up in frequency. We have stable high power sources at 12 and 24 GHz that are
good building blocks for the higher bands. Form an alliance with other s. Use of
specialized test equipment can be arranged by companies if you ask or know
someone. You can sometimes borrow key pieces of equipment until you get your
own. In some cases companies have donated components. It takes commitment and
progress. When others see you are serious and capable, they will help. Just
wishing or engineering will not do it. You have to get in and start building.
Network with other hams that work on the same bands for advice. So any takers?
What is your favorite band? 75 GHz or 144 GHz? Do you dare to go where no one
has gone before? Doug K6JEY

Scheduling:

4 Apr K6JEY, Deep space Tracking Station in Tidbinbilla video. 2003-4
Elections.

1 May Feeding of TWT's

5 June TBD

"Wants and Gots" for sale

Want HP715 Power Supply, X13 Klystron, and HP 809 and 810 unit- Ed K6ODV
909-689-1339.

Want ceramic caps 0.005 uf @ 4kv (5kpf@4kv) Mike W6YLZ 881-349-8525

Want HP432A manual Ken WB6DTA 818-848-9059

Want HP8660 2.6 GHz RF plug-in and Siemens RW2135 TWT tube Frank WB6CWN
805-300-2902

Want- I am looking for two manually operated four port WR-90 waveguide
transfer switches, or two waveguide transfer switches with bad motors/coils that
can be removed, leaving the machined switch pieces. I could probably use
switches that are non-functioning, jammed, or have impractical coil voltages, as
long as they come apart. Frank WB6CWN 805-300-2902

Activity reported at the February SBMS meeting-
Mel, WA6JBD worked on a 10 MHz standard frequency distribution amplifier for his
shop; Rick, W6ESS has a 2 cm transverter; John, N6AX rebuilt his 24 GHz rig;
Dick, WB6DNX did some machine work on aluminum blocks; Chuck, WA6EXV is working
on a GPS frequency lock devise for locking his 10 GHz EME rig and is working on
converting his 10 ft dish to a casagrain feed; Bill, WA6QYR brought in his 2 GHz
helix he plans on using with a dish for AO-40 work; Frank, WB6CWN has a new 10
GHz rig and reworked an older Qualcomm front-end to have a 1 dB NF and 35 dB
gain; Ken, WB6DTA has been working on Pcom documentation; Chuck, W7VX has been
involved in some 432 MHz work; Ed, W6OYJ has 12w on 1296 MHz and did some 24 GHz
rig work and put some new items on the San Diego Web site; Joonho, KG6MQS is
working on a synthesizer; Steve, AD6XQ is working on a Qualcomm 10 GHz rig;
Chris, N9RIN has his Qualcomm rig die and built a DN6NT rig; David, KI6FF had
some parts to give away; Pat, N6RMJ has a 10 MHz battery powered oscillator for
portable operation; Howard, , WA6YGB is working on a stressed parabolic dish;
Ed, K6ODV is rebuilding his 1296 MHz loop yagi antenna after being blown down in
the wind; Jeff, KN6VR is house building; Chip, N6CA indicated that the PV beacon
is down and a new site is in the mill; Dick, K6HIJ is working on the
construction of the wooden block for WA6EXV's sub-reflector; Paul, KH6HME is
still visiting the mainland; Bill, K0AWU is a Central States club member and a
Microwave Update attender; Gary, W6KVC working on 10 GHz ATV; Mike, W6YLZ is
working on 24 GHz hardware; Dave, WA6CGR worked on network stuff; Doug, K6JEY
working with schools on ham gear.

Items off the web--

Breaking the 3456 MHz North American DX record one km at a time.

On February 2, 2003 a high-pressure area set up over the Gulf of Mexico. As a
result, we had some spectacular tropo from Texas to Florida with conditions also
being good to Alabama, Georgia and Tennessee. My best microwave DX in the
morning was to W4ZRZ in EM63 in Alabama on 1296 MHz. Later that evening, I
decided to place a telephone call to Ron, WA8TTM/4 who resides in EL98DP. Ron
had sent me numerous emails updating me on his 10 GHz efforts. At nearly
midnight I get his voicemail which was probably better than getting one's wife
at that hour. WA8TTM showed up on 2 meters some time later. WW2R and I proceeded
to work Ron on 222, 432, 902, 1296, 2304 and even 3456 MHz. The distance from
EM13QC to EL98DP is 1508 km based on the 6 digit grid squares. So, when I worked
WA8TTM on 3456 MHz, I broke my old 3456 MHz record of 1507 km to KQ4PI. When
WW2R tail-ended me and worked WA8TTM, Dave broke my record by one km extending
the North American 3456 MHz record to 1509 km! A part of me said I just gave
away my 3456 MHz record! But oh well.... records are made to be broken. I have
had my share. We had no success on 10 GHz. My equipment on 3456 MHz is a 5 ft
dish and 240 watts output. WW2R was running 5 watts output. I guess my 240 watts
was warming up the atmosphere! Best Regards Al, W5LUA EM13QC Allen, Texas

47 GHz record bump. On Monday, Feb. 9 Bob, KF6KVG, and I made a contact on 47
GHz extending our previous best of 176 km to 246 km. Bob was east of Fresno near
Grants Grove (DM06MS) and I was east of San Jose on Mt. Hamilton (CM97EI). We
first acquired on 10 GHz as an aid in pointing (my compass was not working). We
then went to 47 GHz and acquired in short order, about noon. Signals peaked at
20 db out of the noise with rapid fades up to 10 db. Equipment was the same as
last year except I added a one-watt amp. It was really not needed for the
contact but aided in acquiring. Information was exchanged by slow-speed cw.
Weather was great, about 60 degrees, no wind, and low humidity. Monday was the
last day of about a week of this weather. We had tried this path last summer
without success. We did not try 76 GHz as we had converted those rigs to 144
GHz. Last Friday, Feb 7. We extended our range on that band to 25 km. Likely our
best but a long ways from what the East coast crew did. Will W0EOM

Here is some back-up information on an item that was presented at our last
meeting by Ed Munn.

---------------------------------------------------------

Gentleman:

On my recent trip to SoCal, there was some discussion of a 10GHz beacon
re-installation possibility on Mt. Potosi. There was a beacon there for 1.5-2
yrs, about 8 yrs ago. At that time, the beacon transmitter, under 100mW &
wide band mode, fed an antenna on the roof of a one-story bldg. with waveguide.
The ant. was a small dish, not over 24-inch dia. It was pointed somewhere over
towards Blue Ridge in the San Gabriel Mountains. There was uncertainty about the
frequency. The local sponsor wasn't sure if anyone other than some hilltop
portables had heard the signal in SoCal. There was speculation that it may have
been heard on the Palos Verde's Peninsula. The local sponsor said that he used a
wideband mode rcvr connected to a small dish to confirm continued reception of
the signal locally, off the back of the antenna. There were times during these
receiving periods that the signal was undetectable on the 30 plus mile path to
Las Vegas.

To further this, I contacted a local ham that has extensive interests on Mt.
Potosi. He can provide 2 rack units (2 X 1.75 inches), Rohn 25 tower space &
12VDC with a maximum primary demand of 120W. He indicated that antennas should
be able to stand 100 MPH wind loading & about 1 inch of ice loading under
infrequent condx. There may be other requirements, but I understand that this
would be no ongoing cost to the beacon providers, but all of the equipment for
the beacon and ant. System would have to be furnished. It would probably require
a trip to/from Mt. Potosi for installation & a meeting with the local
sponsor. Perhaps the actual site would have to be analyzed for affectivity.
There are several of us locally in addition to the local sponsor who could be
trained in the necessary procedures in case of problems. A means of detecting
the signal here in Las Vegas would probably be necessary for periodic
monitoring. The I.D. on the beacon would be that of the local sponsor per his
request. The possibility of other frequency beacons may be possible, but 1296
& 2304 won't be welcomed because of other equipment on those bands on
site.

These are mainly amateur ATV applications. A suggestion that an Omni antenna
be used might be OK for local use, but not suitable for the relatively long
distance to SoCal. Also, the previous installation used a limited run of
flexible waveguide, which had enough loss as to make the under 100mW output
levels compromised somewhat. After looking over the portable setups in SoCal, it
was obvious that the xmtr to ant. Connection had to be very short, with the TX
unit mtd right on the antenna. A 2W brick incorporated in the beacon package
might be necessary for coverage. The low Potosi site is 32 mi. L.O.S. from my
house, located in S.W. Las Vegas. In this matter, I am only a facilitator to the
point of helping make this happen if the will is there. Pass the word if there
is interest. 73, Al Olcott--K7ICW (702) 897-8410 [email-masked]

-----------------------------------------------------------------

RF Hazards by K2RIW. 19 Feb 2003 "Richard
T. Knadle" <[email-masked]>

Dear High Power Microwavers,

INTRODUCTION -- The high power Radars of the Marshal Island experience of
Dave, K4TO, and the Trinidad experience of Jim, W4RX are good for illuminating
many of the principles of RF Bio-hazard Assessment. Dave's situation is
calculated here, and I suspect the conclusions could be equally applied to Jim's
situation (repeated below). The aircraft that flew in front of Jim's radar were
probably also at a safe distance. High Power Microwave (HPM) energy is something
to treat with a healthy respect. When in doubt, please err on the side of being
conservative. However, the subject is often misunderstood, and many people
respond in a way that is more emotional than factual. As you will see, the most
dangerous conditions that are possible are quite different from those you would
consider by using "good common sense".

CALCULATION METHOD -- You will notice that calculations are performed in a
step-by-step signal flow manner, so that the RF principles are illuminated. To
many readers this methodology improves the memorization, and it increases the
understanding, compared to simply plugging in numbers to a large equation with
many variables.

K4TO's SITUATION -- Dave, K4TO gave us a "war story" (repeated below)
concerning his experience in the Marshal Islands with one of the world's highest
powered Radar systems. The 10 and 20 Megawatt Radars that fed a 150-foot dish
sound like very dangerous pieces of hardware. As you will see by the following
calculation, they probably were quite safe, particularly considering the way in
which they were being used.

NON-IONIZING RADIATION -- The wavelengths that are far longer (lower in
frequency) than the optical wavelengths are often called "non-ionizing". This
means that the smallest unit of transmission (a photon) at this wavelength
doesn't have enough energy to disrupt the molecules of your DNA. Thus, their
only documented effect seems to be RF heating.

REFERENCE STANDARDS -- Arguably, one of the most authoritative documents on
this subject is the ANSI IEEE C95.1-1991 Standard, published by the US American
National Standards Institute. It has the title "IEEE Standard for Safety Levels
with Respect to Human Exposure to RF Electromagnetic Fields, 3 kHz to 300 GHz".
This document contains 450 references from many of the world's best research
institutes, and it describes the compendium of opinions on this subject that
have been gathered over the last 50 years. The RSGB uses a similar document that
is recommended for the UK by the National Radiological Protection Board
(NRPB).

MPEs -- The latest version of these documents describes the Maximum
Permissible Exposure (MPE) levels that are allowed at various frequencies. It is
interesting to note that the most stringent MPE is for the VHF frequency region
of about 30 to 300 MHz. In this frequency region human tissue absorbs a majority
of the RF energy that impinges on it, and converts it into heat. The most
vulnerable organs are the eyes (possible cataract genesis) and the reproductive
organs (possible temporary or permanent sterility), due to the fact that these
organs have a low heat tolerance, and a restricted ability to dissipate
excessive heat.

OTHER FREQUENCIES -- At lower RF frequencies a majority of the RF energy
passes through human tissue and is not absorbed. At higher RF frequencies a
majority of the RF energy is reflected at the skin surface. The so-called
Microwave region above 1,500 MHz has an MPE that is 5 times higher than the 30
to 300 MHz region. To repeat, Microwaves are pound-for-pound 5 times safer than
VHF frequencies.

SAFER MICROWAVES -- Although this is well documented, try to convince your
local Zoning Board of this fact, and they are likely to think your are crazy. In
the last 10 years I have given testimony before 12 Zoning Boards while defending
amateur radio towers on Long Island, New York. The task is very challenging.

THE ALTAIR RADAR -- Dave's (K4TO) Marshal Island "Altair" Radar had a peak
pulse power of 10 MW (at 155 MHz) and 20 MW (at 422 MHZ). Believe it or not, the
most dangerous condition would occur if that RF power was radiated directly by
the transmission line to that Radar dish. If the 422 MHz wave guide flange was
simply "open circuited" to the air, that would constitute an "antenna" that has
about 6 dB of gain and a VSWR of about 1.4:1. A person standing near that open
circuited WG flange could absorb the average power of the RF transmitter (that
hits him) and is converted into heat. If the vulnerable organs experienced a
significant rise in temperature, than possible damage could occur.

THE DUTY FACTOR -- I'm assuming that the Altair Radar was a Long Range Search
Radar, or an Over-the Horizon Radar. It is likely that the Radar had a pulse
duty factor of 0.25% (0.0025) or less. Thus, the average transmitted power was
probably about 50 kW. The ANSI C-95 specification says that the most stringent
MPE for a "controlled environment" in the VHF frequency region is 1.0 milliwatt
per square centimeter, averaged over a 6-minute period (360 seconds). The
standard assumes that the vulnerable organs have a thermal time constant of 6
minutes.

SAFE DISTANCE -- Let's calculate how close you would have to stand to that
open-ended WG flange to experience that MPE. This is done by assuming that the
signal source radiates isotopic ally on the inside of a uniform sphere, and we
must calculate how big a sphere is required for the Power Flux Density (PFD) to
go down to 1.0 mW/(square cm). Remember that 1.0 mW/(sq. cm) equals 10
watts/(square meter).

The transmitter's 50 kW average with a WG flange gain of 6 dB equals an
Effective Isotropic Radiated power (EIRP) of 200 kW average. A sphere that has
an area of 200,000/10 = 20,000 square meters would be just right. The sphere's
area is equal to 4*Pi*R^2 = 20,000 m^2. Solving for R equals 39.9 meters (131
feet). Therefore, a safe distance to the opened WG flange is 131 feet.

THE COMPLETE RADAR -- When the Altair Radar is operating, the feed horn tries
to evenly distribute the 50 kW of average power over the surface of the 150-foot
dish. That would give the dish the maximum possible gain of 46.1 dBi at 422 MHz.
The best the horn can do is to create a 10 dB amplitude taper, which lowers the
dish efficiency to about 60%, and the gain will be about 43.9 dBi (1.2 degrees
of beamwidth).

THE PFD AT THE REFLECTOR -- The 150 foot dish has a projected surface area of
17,671 square feet (1,642 square meters), if it is a round dish. If the horn
could evenly distribute the 50 kW of RF energy on the dish surface, that would
equal a PFD of 30.5 watts/(square meter). Because of the amplitude taper and
edge spillover the PFD at the center of the dish is probably about 4 times
greater, or about 122 watts/(sq. meter). This PFD is 12.2 times the current MPE.
Because the ANSI Standard has a 10:1 safety factor built into it, that might
actually be almost a safe exposure level. In other words, you could lie at the
center of the dish while the Radar is operating for 360/12.2 = 29.5 seconds, and
be safe by the most stringent portion of the current ANSI standard.

COLLIMATION -- The parabolic surface of the dish takes the spherical
wavefront from the feed horn and collimates it into a nearly parallel beam. As
you stand at some distance in front of the dish, the spread of the energy will
cause the PFD to drop below the 122 watts/(sq meter) level.

NEAR FIELD RANGE -- Let's see what happens if you stand at the best distance
in front of the dish. A 150 foot dish at 422 MHz has a Near Field Range of
2^D^2/Lambda = 19,294 feet (3.65 miles or 5.9 km). At that distance (or greater)
the dish achieves about the best performance of Gain and Pattern. 50 kW
(average) into a dish with a gain of 43.9 dBi yields an EIRP of 1.23 GW, or 121
dBm (average power). At 3.65 miles at 422 MHz the Free Space Loss is equal to
-100.3 dB. An Isotropic antenna in the boresight of that Radar at a distance of
3.65 miles would receive an average signal of 121 -100.3 = +20.7 dBm. An
Isotropic antenna has an Effective Area of Lambda^2/(4*Pi) = 0.04 meter^2.
Therefore an Isotropic signal of +20.7 dBm (117 mW) equals a PFD of 0.117/0.04 =
2.9 watts/(square meter). This is an MPE that is 3.4:1 below the current ANSI
Standard of 10 watts/meter^2, and it is actually a safe PFD for continuous
exposure.

DECREASING DISTANCE -- If you were at 3.65 miles in the boresight of the
Altair Radar and you began walking toward the dish, the PFD would increase by
less than 15 dB and peak at a distance of 1/5 the NFR, than it would decrease by
3 dB and continue to oscillate between two levels that are less than 3 dB apart.
As you get closer two things happen: (1) the Free Space Loss decreases; (2) the
apparent dish gain begins to decrease because portions of the reflecting surface
becomes out-of-phase at your range. Experience with most dishes has shown that
rarely does the PFD become more than 15 dB stronger than it is at the Near Field
Range, and it almost never exceeds the PFD that exists at the apex of the dish
reflector, unless the dish was intentionally made "nearsighted" by translating
the horn beyond the normal focal distance.

The maximum PFD would occur at 1/5 of the NFR, or 0.73 miles. At that
distance the 15 dB increase in PFD (from 2.9 Watts/meter^2) would be 92.4
watts/meter^2, which is below the estimated PFD at the apex of the dish
reflector -- that was about 122 Watts/(sq meter). These worse case PFD's are
very close to the old MPE, which didn't have the recently added 10:1 safety
factor.

At a 1.0 mile range (0.27 of the NFR of 3.65 miles), where Jim's living
quarters were, the calculated PFD will increase by 10.9 dB, and increase from
2.9 W/m^2 to 35.7 W/m^2. That's 3.6 times the current ANSI Standard, but
considerably below the standard that existed at that time (100 W/m^2). Thus, it
was prudent that his living quarters were RF shielded structures.

All of these calculations assume that the dish is continuously staring in a
particular direction -- that's the worse case condition. If the dish was
continuously rotating, then the Biohazard assessments become many times safer,
as long as it doesn't dwell for 6 minutes in a particular direction that
contains biological material.

CONCLUSIONS -- The surprise of a real-world Radar situation is that the RF
Biohazard actually decreases when you use a higher gain dish antenna. This is
because it distributes the transmitted energy over a large surface area, and the
PFD always decreases from that point as the range is increased. A bird that
lands on the feed horn while the Radar is operating will probably not survive
for more than a couple of minutes. Birds like to do this when the dish is not
rotating. Under these conditions Radar operators will sometimes find dead birds
lying below a Radar dish.

A naive technologist will sometimes use the peak power of a Radar instead of
the average power. Then they will simply add the antenna gain (in dB's) to the
peak transmitter power (in dBm) to calculate the EIRP. This methodology can give
results that are doubly pessimistic in assessing the near-by RF Safety. They
failed to realize that RF primarily creates a heating effect, and the heating is
proportional to the average power, not the peak power. Also, the full antenna
gain is only realized in the Far Field. When you're up close, portions of the
antenna are out of phase, and do not fully contribute to the resultant PFD.

I hope this material is helpful in increasing the understanding of RF
Bio-hazards. Feel free to correct the math errors. 73 es Good VHF/UHF/SHF DX,
Dick, K2RIW. Grid: FN30HT84DC27.

Web: http://consult-li.com/listings/Rknadle.htm

Good morning,

As long as we are swapping "war stories" I might as well put my hat in the
ring. For five and a half years I worked In the Marshall Islands. Some of you
may even have worked me as KX6DS. I was employed by the folks who ran the ALTAIR
radar site. ALTAIR is a dual band VHF/UHF radar using a 150-foot dish. The
transmitted power on VHF is 10 Megawatts and on UHF 20 Megawatts, peak. This is
BEFORE it gets to the 150-foot dish. You make the calculations on ERP.

We had safety limit switches that would disable the transmitters below a
certain elevation and within certain azimuth limits that pointed at the living
quarters, which were a mile away. Also on the island was another radar called
the millimeter wavelength radar. I don't know the power or frequency of that
one, but before it was fired up, a truck with a red light and siren was sent all
around the island (The island was about 1 mile in diameter.). Nobody was allowed
outside while this radar was on. All of the building on the island were RF
shielded. BTW, the ALTAIR frequencies were 155 and 422 MHz. I was the receiver
engineer and my "receiver" consisted of 60 six-foot racks of electronics. There
were eight feeds coming from the dish, LC, RC, Az, and El for each radar. All
signal paths had to be phase matched to within less than a degree. I am trying
to remember what sort of test equipment we used, but I believe my present bench
setup with a 22 GHz spectrum analyzer and 18 GHz counter exceeds the capability
that I had on the island :-) Thanks for allowing my to reminisce a bit. 73,
Dave, K4TO

-----------------------------------------------------------------------------------------------

During the February SBMS meeting Chuck
Swedblom, WA6EXV was presented a Life
Time Achievement Award for his efforts to promote amateur radio
microwave activity and technology. This is the text from that presentation.

Chuck was born in Montana on February 19, 1926. The family moved to Idaho
when Chuck was 6 years old. They had a small ranch near McCall, Idaho. Chuck
learned many tasks while ranching. His father ran a pack train for the U.S.
Forest Service and did guide and pack trips for private hunting groups. Later
Chuck would work as a Forest Guard putting in lookouts and running phone lines
into the back country. He would also be a fire fighter when that was needed.
Skiing was also part of Chuck's life in High School. Chuck joined the Navy and
went through electronics and radio schools. He was stationed on Hawaii from 1943
to the end of the war, where he took care of transmitters for the pacific
operations. He became a licensed amateur some time during 1943. His call was
W7JHX.

He married Jean in 1946 and moved to Moscow, Idaho where he attended the
University of Idaho, and later to Kansas, where he went to Central Radio &
Television School, in Kansas City, MO. His call while in Kansas was W0OZH.

After returning to Idaho he worked for a Radio Supply Company in Boise.
Having joined a Naval Reserve Unit while at the University of Idaho, he was
active in a reserve unit in Boise. He was called to active duty during the
Korean conflict and was stationed at the Tongue Point Naval Base in Astoria
Oregon. Following discharge, he moved his family to Port Orchard, Washington
where he managed a radio and TV service shop. During this time he played with HF
and VHF radios and experimented with ATV over 10 GHz.

Chuck worked for Philco Corporation Technical Representative Division and was
stationed at Edwards Air Force Base Rocket test site in the late 1950's. Since
then his call sign has been WA6EXV. He was transferred to the Navy Lab at Corona
California and was assigned to the naval base at China Lake in 1960. In 1966 he
became an employee of the government at China Lake where he retired in 1987.

Chuck and Jean moved to Ridgecrest in the 1960's and eventually to their
present location between Ridgecrest and Inyokern because it had better VHF path
to Southern California and he could put up bigger antennas than in the city.

When Bill, WA6QYR moved to China Lake in 1969, he met Chuck. Chuck became a
member of SBMS that Bill had joined a couple of years before. The two have been
driving to monthly meetings ever since.

During the period from 1972 to 1974 Chuck was instrumental in designing a 2.3
GHz beacon to go on board Oscar 7. Working along with Chuck were Gordon Lowery,
WA6ZKY, Dick Kolbly, K6HIJ and Frank Adams, W6BPK.

In 1973 Chuck took the five foot rack full of vacuum tubes ROCKLOC design and
turned it into a Solid State ROCKLOC design when running transistors at several
hundred volts was still a novel idea. Klystrons took little current but three
hundred volts for the repeller and negative 600 volts for the cathode.

In 1977 Chuck built a ROCKLOC system with a solid state 10 GHz Gunnplexer
instead of a klystron. This wideband fm XCVR design was published by Microwave
Associates in an Application Note that appeared in May 1977. An updated version
using the RCA CA-3089 fm if amplifier/detector is still published in the ARRL
Handbook.

In the spring of 1978 Chuck had taken an old telemetry transmitter and
converted into a beacon with ID'er and it was installed as the First 2.3 GHz
Beacon on Heaps Peak.

Antennas were another area of interest to Chuck. He built his own antenna
range in order to test his designs and projects of other amateurs.

Solid-state oscillators were coming on line in the late 1970's and by
mid-80's they had grown in power capability. In 1987 Chuck designed and built
two high-power 100-milliwatt Gunn 10 GHz sources. He gave one to Ed Munn W6OYJ
who used it to take top score in the next ARRL 10 GHz Contest, outscoring Chuck
by only 300 pts out of 10,500.

As technology progressed, so did Chuck's projects. In the 1990 time period a
commercial surplus of Microwave Associates 12 GHz data transmission units became
available through some surplus dealers. Chuck took some of the hardware and
converted them to the amateur 10 GHz band use and provided documentation to the
amateur microwave community.

Over the years, Chuck has produced several excellent LNA designs for 10
GHz.

Also in the 1990 time period Chuck designed and built a Kilowatt Transmitter
for 13 cm EME using a Microwave Oven Magnetron. His excellent article was
published in the Jan 1991 Communications Quarterly Magazine. In May 1992 the
first California 10 GHz EME QSO was from Chuck, WA6EXV Ridgecrest to Jim, WA7CJO
in Phoenix.

In July 1993 Chuck and Phil Lee, W6HCC set the North American 10 GHz
Terrestrial DX record from Mt Pinos to Mt Ashland Oregon; 537 miles/865 Km. This
was the 2nd attempt over the long path.

Between 1991-93 Chuck and Phil teamed up to see how many grids they could
work on 10 GHz from Heap's Peak, and later from Keller Peak. As of 1994 they
reached 31 Grids for Chuck and 34 for Phil.

In 1994 Chuck and Phil made the first California-to-California 10 GHz EME
QSO. This was from Chuck's QTH in Ridgecrest to Phil in Beaumont.

In Dave Laag, K6OW's outstanding 1994 article on SBMS History, he stated he
wanted to choose one SBMS figure from the last 25 years who had had the most
influence on local and general Amateur Microwave progress. Paraphrasing Dave's
article---- Chuck Swedblom, WA6EXV brought the rest of us from the older
technologies like klystrons..... to rapid deployment of newer technologies,
first to Gunnplexers, then "Narrowband" and finally PHEMTs and the moon. Dave
then repeated a statement made by Frank, WB6CWN, that efforts such as those by
Chuck "allowed the rest of us to look great while standing on the shoulders of
giants".

By 1996 Chuck had continued to push our boundaries by moving up to the 24 GHz
band, first with Gunn wideband systems. That year the ARRL added "and UP" to the
10 GHz Contest, and Chuck finished in third place with a combined band score of
over 12,000 points and best DX of 178 Km. on the higher band. He experimented
with higher power Gunn sources but was unhappy with their drift problems. This
drove him to work toward 24 GHz narrowband capability, including the need for
decent LNAs and stable LOs. By 2000 he was operating with a "thoroughly modern",
all homebrew 24 GHz rig and urging the rest of us to join him.

A major SBMS effort began in 2001 to replace the twenty year old 2.3 GHz
Heap's Peak Beacon. Chuck, working with hardware from Sam K6VLM along with some
of his own designs built the new 1.2 to 2.3 GHz beacon- translator and antennas
that were installed in November of 2002. As part of this effort a main antenna
goal was to have omnidirectional horizontal polarization with significant gain.
Chuck discovered major problems with widely accepted Slot Antenna design
formulas and software, produced an excellent antenna, and disseminated the
results to other microwavers. This is a good example of the thoroughness he
exhibits in every project, and in his desire to share his findings with
others.

Chuck has been there for us, and has been pushing us to have better equipment
and make longer distance contacts.

On behalf of the San Bernardino Microwave Society it is my privilege to
present Chuck Swedblom with the Society's Lifetime Achievement Award.

73's Bill

Chuck Swedblom, WA6EXV (left) was presented the
SBMS Life Time Achievement Award at the February meeting by President Doug
Millar, K6JEY

The San Bernardino Microwave Society is a technical amateur radio club
affiliated with the ARRL having a membership of over 90 amateurs from Hawaii and
Alaska to the east coast and beyond. Dues are $15 per year, which includes a
badge and monthly newsletter. Your mail label indicates your call followed by
when your dues are due. Dues can be sent to the treasurer as listed under the
banner on the front page. If you have material you would like in the newsletter
please send it to Bill WA6QYR at 247 Rebel Road Ridgecrest, CA 93555,
[email-masked], or phone 760-375-8566. The newsletter is generated
about the 15th of the month and put into the mail at least the week prior to the
meeting. This is your newsletter. SBMS Newsletter material can be copied as long
as SBMS is identified as source.

San Bernardino Microwave Society newsletter

247 Rebel Road

Ridgecrest, CA

93555

USA