50 MHz & Up Group

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The 50 MHz and Up Group is an educational and public service amateur radio organization centered in the San Francisco Bay area. The group is interested in developing and utilizing communications on frequencies from 50MHz up through light-waves. The group is open to any related topics that might be of interest to members, such as: technology, design, construction, operation, public service, contesting and antennas.
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Contact

For questions about this group or about programs and activities, please contact the 2020 President, Mike Lavelle (K6ML):  miclevel at comcast.net

In-person meetings are cancelled and replaced with virtual meetings

We've cancelled the usual in person first Tuesday meetings while we're sheltering in place. Instead, we will hold an on-the-air virtual meeting on the first Tuesday:
Our April meeting will be on Tuesday April 7 beginning at 7pm on the Bay-Net FM analog linked repeater system. We will run the meeting as a net, with check ins starting at 7pm.
Round table discussion (everyone can report on their projects and operating activities, ask questions, etc), followed by Tech Talk: "Path Selection - Propagation Prediction for Millimeter Wave Operation", Mike, K6ML.

Here is a link to the repeater system description:
click here for the Bay Net analog FM repeater information

East Bay:
443.975 PL 100.0 +5 MHz offset (448.975 input)
South Bay:
145.390 PL 100.0 -600 Khz offset (144.790 input)
443.225 PL 100.0 +5 MHz offset (448.225 input)


Please download the slides for the tech talk before the meeting so that you can look at them during the talk.
click here to download Mike's PDF of his slides

We also have an on-the-air net on our 10GHz repeater/translator

Please join the 10GHz translator net on the last Tuesday at 8pm. You may also share ideas using our email reflector. (you must be a member to use the email reflector)

Minutes from the March Meeting by Brian Kline

Mike Lavelle (K6ML) called the meeting to order at 7:01PM.

Announcements:
The SBMS 2 GHz and Up Contest will be May 2-3.
The first Electronic Flea Market of the year at the Sunnyvale Frys Electronics parking lot has been canceled. For more information see (www.ElectronicsFleaMarket.com)
Microwave Update 2020 will be in Sterling, Virginia, October 15-18.

There was no old business, and no new business. That ended the formal meeting, which was followed by a presentation by Goran Popovic (AD6IW) on 10 GHz LNA amplifier design.

Then Mike Lavelle gave a presentation on his successful contact from Mt Vaca to Mt Umunhum on 122 GHz, with N9JIM and KB6BA.

The presentations were followed by a brief discussion of current VHF and Microwave related activity.

The meeting was adjourned at 8:50 PM

2020 dues and member information must be updated

If you have changed your address, email, phone, other info, please send a simple email to jpawlan@yahoo.com
If nothing has changed at all, then once a year please send an email saying nothing has changed. Make sure you state whether your email address has been changed or not.
To send a memberform with your updated information or to join, please go to the Membership tab of this website.
Dues are $10 for a year, $15 for two years. This must be sent to the new Treasurer:
Oliver Barrett
1111 Pecos Way
Sunnyvale CA 94089

Make your check payable to 50MHz and Up Group of N. Calif Inc

Goran, AD6IW has provided his lecture "Low noise amplifier design and implementation" for everyone who could not attend. It is available in MS Powerpoint and also in Acrobat PDF formats here:


Please click here to view or download the Powerpoint version.

Please click here to view or download the Acrobat PDF version.

New World Distance Record on 122GHz

On Feb 17, 2020 a new distance record was established on 122GHz: 139km
Mike, K6ML, was on Mt Vaca (CM88WJ75ON, 835m ASL) and Oliver, KB6BA, and Jim, N9JIM, were both on Mt Umunhum (CM97BD18VJ, 1016m ASL)
The antennas were 60 cm satellite TV dishes and the transmit power was less than half a milliwatt of output power on 122 GHz. The complete transceivers were on a chip by Silicon Radar and they were designed as sensors.
The received signal level was very weak: 7 dB above the noise in 22 Hz; -13 in 2500 Hz equivalent with QSB down to the noise floor.
Dish alignment was done on 24GHz where the signal levels were very strong.
This had to be planned according to the weather as the water absorption is very great. The weather the morning of the contacts was Dew Point -11C, Air Temp +15C, path loss ~ 225 dB, atmospheric loss ~0.35 dB/km

Mike posted some video and audio on youtube: click here for youtube



the 2020 Officers

Mike Lavelle (K6ML) president
Pete Mahowald (K6TJ) vice president
Brian Kline (WA6QDP) secretary
Oliver Barrett (KB6BA) treasurer
Paul Zander (AA6PZ), director
David Fifield (AD6A), director
Stuart Neubarth, (WA6SFI), director

Beacons

Microwave Beacons in operation The following beacons are known to be operating as of 06-30-2019:

NameGridCoordsFreqCallPowerAntComments
Mt Vaca CM88wj 38.415, -122.116 10368.325 W6ASL +30dBm 10dBi omni CW ID
Mt Allison CM97bl 37.500, -121.872 10369.000
10369.033
10368.433
24192.010
47088.000
K6MG


N6NU/B
KF6KVG
+21dBm
+29dBm total out

+13dBm
+7dBm
10dBi omni
"
"
12dBi omni
+20 dBi horn 27 deg beamwidth, aimed SW
CW ID, locked, S-meter output
Linear translator: Output is 11-55 kHz above beacon
Input 600 kHz below desired output
CW ID locked
CW ID locked
Mt Leeson CM97ae 37.167, -121.924 10367.990
24191.975
47087.99
79919.92
KF6KVG +20dBm
+20dBm
+5dBm
-5dBm
2.5" horn
1.5" horn
1.25" horn
0.6" horn
FM ID, locked, aimed NW
FM ID, locked, aimed NW
FM ID, unlocked, aimed NW
no ID, locked, aimed NW
Bear Mtn. DM06ir 37.747, -119.281 24191.990 W6BY/B +27dBm 20 slot omni locked, IDs as DM07IC, will fix
Mt Frazier DM04ms 34.775, -118.969 10368.310 N6CA/B +31dBm 14dBi omni CW ID, locked
Heaps Peak DM14kf 34.235, -117.141 10368.370 ? +?? dBm ??dBi omni CW ID
Palos Verdes DM03ts 33.747, -118.336 10368.300 N6CA/B +32dBm 14dBi omni CW ID, locked
Santiago DM13fr 33.712, -117.534 10368.330 KE6JUV +27dBm 10dBi omni CW ID, locked
San Miguel DM12mq 32.697, -116.935 1296.297
3456.360
5760.000
10.368360
K6QPV/B


unknown
unknown
unknown
unknown
unknown
unknown
unknown
unknown
xtal few Hz
CW ID, locked
CW ID, locked
CW ID, locked