W6IFE Newsletter

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

Vice President: Dick
Bremer, WB6DNX 1664 Holly St. Brea, CA 92621 714-529-2800
[email-masked]

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

Corresponding Sec: Kurt
Geitner, K6RRA 213 Main St. #5 Seal Beach, CA 90740 310-718-4910
[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

ARRL Interface Frank Kelly, WB6CWN 1111 Rancho Conejo Blvd. #501 Newbury
Park, CA 91320

805-499-8047 [email-masked]

FCC Interface Dave Laag, K6OW 11614 Indian St. Moreno Valley, CA 92557
909-924-1517

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

[email-masked]

The 2 August 2001 meeting of the SBMS will
be a planning and work session for the upcoming 10 GHz and Up contest. 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 Dick Kolbly, K6HIJ talked about his experiences constructing a
24 GHz waveguide switch. Drawings of his switch are in this edition of the
newsletter. Dick says the switch is simple in concept but tolerances are the key
to making it work. With 0.002-inch clearances there are leakage and resonance's
to deal with. A number of fixtures had to be built to machine the individual
parts for the switch. Making the rotator with 90-degree rotational positions was
a big problem. The first compete switch had 40 dB isolation and 21 dB return
loss as measured by Chuck, WA6EXV. Dick wants more in the way of 60 dB isolation
and will be trying different chocks and tolerance improvements. Dick plans to
build a power measurement test bench so he can try different machining
techniques without the turn around time of sending the device off to Chuck for
measurement. Super Project and report Dick. Dick's handouts are included here.
Thanks.

Dick, K6HIJ reported visiting the Antique Radio Museum in Bellingham
Washington, which has various aspects of radio history displayed. The museum
owner eventually hopes to have a test bench from the early 1900's time period
for the repair of radios from that time period. Amateur radio is also part of
the display. Dick proposed that the society assemble a group of items and
documentation for an Amateur microwave display in the museum. Dick is to write
up a proposal for membership agreement next month. The plan is to have folks
with the desired pieces of historic hardware and documentation adds to the
collection to be sent. The membership voted to supply $50 for the reproduction
of photographs. Suggested committee members would be K6HIJ, K6JEY, K6MBL, WA6QYR
and others. Chip, N6CA announced that the Western States Weak Signal Society was
looking for microwave articles to be published in the proceedings for the
September convention in Ventura. Articles needed to be received by mid August
for inclusion. There was lots of discussion about the upcoming 10 GHz and Up
culmative contest. Chuck, WA6EXV plans to be on Cory Pk in September for some
long 24 GHz narrow band shots. Welcome to visitors Doug Cabell, KA6CAT of
Huntington Beach and to Dale Cabell, N6AQQ of Santa Ana. 21 people present on a
hot humid July meeting.

The Prez Sez. While you are musing over your microwave rig and getting it
ready for the contest, remember to put a telegraph key on it. More precisely,
put a device on your radio that you can send code with that is unobtrusive, hard
to leave behind and won't be harmed by handling the rig and dish. You would

be surprised at how your code comes back to you when you are struggling with
your best DX QSO. However, if you don't have the connector, some wire and
something to send with, it is very hard to send code. (A show of hands please,
for those who have done a whole QSO with the PTT switch or TR switch).

In my case the poorest choice was a J-38. It was fine on the desk, but ended
up in the box about the time I needed it and was hard to send with. So, instead
of thinking about a key, I began to think about a device that would accomplish
the same thing. Some choices might be: a micro switch with a flow sensor leaf on
it, a relay that you can hand actuate, or a tiny finger key. Be sure to put it
in a place that won't throw the dish off its pointing when you send. You could,
but you would end up sending a kind of weird code. Check out some of the web
pages for keys that feature QRP rigs such as: http://www.frontiernet.net/
~embres/qrp-lionks.htm. Good luck with your rigs and see you at the get ready
session in July as well as on the air during the contest. Doug Millar

Activity reported at the 5 July SBMS meeting; Doug, K6JEY had some 10 GHz
contacts during the June contest; Mel, WA6JBD finished his conversion of an
original MA/COM 10 GHz rig and it is to have a 1 dB LNA and a 2 w amplifier, he
also did some testing of surplus commercial 6 GHz TWTs; Ken, WB6DTA was in DM22
for June with lots of 6 mtr contacts; John, KJ6HZ built a 2 GHz Helix antenna
and did some 10 GHz work; Kurt, K6RRA had some 10 GHz coaxial cable problems
during June contest but did manage to contact N6CA in Mexico; Visitor Dale,
N6AQQ did some 10 GHz gunnplexer work in the 80's; Visitor Doug, KA6CAT has been
doing 800 MHz work; Dave, WA6CGR had contacts with the Mexico crew during the
June contest and did some 10 GHz contacts during Field Day; Chip, N6CA related
some of his experiences in Mexico which had some 38 microwave contacts during
the June contest at ranges from 200 miles to 400 miles. Contacts with WA6MEM
airmobile on 10 GHz. Lots of rovers out now with 900, 1200 and 2300 MHz gear.
Again weather made contacts interesting in that low altitudes seemed to be
better along the coast. Dick, K6HIJ visited Washington State and did his
experiments with the waveguide switch; Chris, N9RIN did some 10 GHz transverter
work; Bob, W6SYA was out in June with lots of contacts and WB6DTA and W6TSK came
over and helped rearrange antennas on his tower so he has 1296 and 2304 MHz on
the air now; Gary, W6KVC did some ATV work; Chuck, N6EQ was out in June with the
WA6CGR group in Diamond Bar and made contacts into Mexico; Frank, WB6CWN was out
in June without liaison radio and was happy to find many contacts just like on
HF by calling CQ; Robin, WA6CDR worked on the antennas of Frazier beacon while
the tower is to be raised. The Beacon is to be back on the air for the contest
one way or another. Dick, WB6DNX was on with the Diamond Bar group in June and
has straightened out a dish bent by the wind; Jeff, KN6VR did some 1296 MHz
work; Chuck, WA6EXV is rebuilding his 24 GHz narrowband RF deck, was on field
Day with 10 and 24 GHz to WA6QYR, and is packaging the 1.2/2.4 GHz Heaps Peak
translator using K6VLM translator and WA6EXV power amplifiers; Bill, WA6QYR
responded to a San Bernardino Sun Newspaper reporter as did several other
members for an article about amateur radio, participated in the Ridgecrest ham
club Field day with 10 and 24 GHz radios; and the oscillator controlled by the
GPS is settling in much better now. Dick, K6HIJ has contacted the San Bernardino
Sun reporter Greg Patton about the article on the Society and will have it
prepared for Chip to put on the web page.

Badges- the following badges are available from Dick, K6HIJ&emdash;AC6RM,
Martin; AD6QL Carl; AL7EB Ed; K0BGL, Dale; K6ENS, Charles; KC6TFS, John; KE6BAA,
Ed; KE6RCI, Eric; KF6HQC, Fred; KN6VR, Jeff; N2LIV, Bruce; N6DN, Paul, N6LL,
Paul; NN6W, Gary; W6KL, Dave; W6ORG, Tom; W6ZKZ, Vince; W7CS, Chuck; W9DHK,
Peter; WA5DJJ, Dave; WA6WAK, Charles; WA6YOJ, Gene; WD4MUO, John; WQ6S,
Steve.

Scheduling

4 August UHF Contest

18-19 August ARRL 10 GHz and Up Cumulative contest 1st half

6 September Program TBD

8 September ARRL September VHF Contest

15-16 September ARRL 10 GHz and Up Cumulative contest 2nd half

Wants and Gots for Sale

For Sale: Un-modified MA/COM units; 10 mtr HTS 100; 2-mtr DEM transverter,
MA/COM dish, tripod Ed K6ODV 909-689-1339

Want info from anyone who knows how to compute power factor from arbitrary
waveforms- dick K6HIJ 760-253-2477

Want sensor head for thermistor head for HP 432 Mel, WA6JBD 909-369-6515.

Want service manual for Systron Donner 1502 Signal Generator Sam K6VLM.

Want HP 1 MHz/ 10 MHz 101A manual or circuit, Dick WB6DNX 714-529-2800.

Hi Bill, Your SBMS July Newsletter reminded me to upload the DX Site List to
the SBMS Web Pages, San Diego Technical papers section. As suggested by K6HIJ I
have added elevation data to the sites when available. The list is in Adobe
(.pdf) format so users will need an Adobe Acrobat Reader program to download and
recover it. 73s from Ed, W6OYJ (858) 453-4563

Hi Bill, More activity on 24 GHz. On 28 June 2001, we set a Colorado record
for 24 GHz. Don, N0UGY went to Pikes Pk. DM78LU. The first contact was to my
home QTH DN70LT. This is a distance of 135 miles. Signals were S9. I then
traveled to DN70OX on Rt 85 near the Colorado/Wyoming border. Signals were also
S9. This is a distance of 147 miles. I was accompanied by Phil, AA0BR, who also
made the contacts. Don is running 1 watt to a 12 in. dish. I am running 60 mw to
a 24 in Macom dish. Phil also runs 60 mw and uses a 20 in dish. We used 10 GHz
to establish pointing. Don has a dual band feed and I can put my 30 in x-band
dish on the same mount as the 24 GHz dish. 73, Phil, W6HCC

Hola, go to: http://www.ham-radio.com/wa6mem/ for the pictures and story of
Gary's aeronautical mobile X-band operations in the June contest. 73 Chip
N6CA

Hello Microwavers, Using a search engine I accidentally discovered web pages
by Brian Yee that describe some of the 21-23 GHz LO Bricks made by DMC, that can
be useful in building a 24 GHz xvrtr. The URL is:
http://reality.sgi.com/byee_mti/dmc.html. Info includes color-coding of wire
leads, voltages, and frequency ranges versus model numbers of some of the
bricks. 73s from Ed, W6OYJ (858) 453-4563

Here is the simplest 432 MHz IF t/r switch. None! I have used this on my
latest 24 GHz rig and it works fine. This scheme will not work on 144 MHz. Too
much reverse loss. Start with a bias tap to extract the +12 volts which ICOM
radios provide at their antenna output terminal. This is present during receive
and goes to OPEN circuit during transmit. This voltage is used as a logic signal
to control T/R functions in the transceiver. Next is a 20 dB power attenuator
from the IF radio to the transverter. I am assuming 5 watts or less out of the
radio. This reduces the power from 5 watts to 50 mill watts. (+37 dBm
&endash; 20 dB=+17 dBm). Next in the line is an IF preamp using a
Mini-Circuits MAR-8. This amplifier is rated for 100 mill watts at the input or
output with no damage. At 432 MHz it typically provides 26 dB gain. The MAR-8 is
between the power attenuator and the microwave mixer. Its 26 dB forward gain
provides 6 dB net gain with the 20 dB power attenuator. (The noise figure of the
ICOM 820 is degraded by about 1 dB.) The reverse loss of the MAR-8 is
&endash;27 dB. This reduces the +17 dBm from the attenuator to
&endash;10 dBm at the mixer. NO Switching! Power is left on the MAR-8 for
both transmit and receive. Reverse linearity is good and no distortion is noted
on the transmit signal.

Transmit +37 dBm +17 dBm -10 dBm to mixer

Receive 6 dB net gain -20 dB 26 dB gain

IF Radio bias tap power attenuator MAR-8 IF post amp Microwave mixer

(ICOM 820) 12 v 20 dB post-amp +26/-27 dB RX/TX

Control Hope this is useful. 73's Phil W6HCC/0

Here is founder Tommy, W6IFE and Don, W6RNA with their 1950's microwave rigs
in Don's back yard. Photo from K6MBL files. 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. 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

73's Bill