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. Lean more . . .
For questions about this group or about programs and activities, please contact the new President, Mike Lavelle K6ML: miclevel (at) comcast [dot] net
Renewal and annual dues are due now.
For those who live within the Bay area, the annual dues for 2015 are $10 per year or $15 for 2 years. This must be sent via mail to the new Treasurer, Jerome Peters AF6UX or bring to the meeting and hand it to him. Make the check payable to: 50MHz and Up Group of N. Calif.
19902 Baywood Dr
Cupertino, CA 95014
Those living outside of the Bay area do not pay dues and as Friends, do not vote. Regardless of whether you are a full Member or you are a Friend, we are required to have a current database.
If none of your information has changed since last Feb, then please send Jeffrey Pawlan WA6KBL an email simply stating "nothing changed". If your phone or email or street address has changed, then you will need to fill out a complete new memberform. See the Membership link for instructions.
Our next meeting of the 50MHz and Up Group of N. Calif will be a regular meeting on Thursday Mar. 5, 2015 at 7pm. Our meeting will be at the usual TI conference building, room 2. You get there from Kifer Rd as shown on our meetings page (click on meetings in the selection bar)
We spent a great deal of time in the roundtable in Feb. so Larry did not get to do his technical talk. He will continue with it at this March meeting. Larry, W3LZ, will present the second part of his presentation on phase noise cancellation. After a quick review of the basic concept presented at our Nov meeting, Larry will explain more clearly how use of an FM detector that has no local oscillator will deliver enough signal to be useable, even for very low levels of phase noise. He will also explain the difference between canceling phase noise and other broad band energy and canceling monochromatic features, such as spurs.
2013 Group Project Notes: Building 10 and 24 GHz Radios
In 2013, we launched a club project with two goals:
- help microwave newcomers to build their first 10 GHz radio
- help club members to build a dual band (10/24 GHz) radio
Here is a new project description file:
Please click here to view or download the project overview slides from our March 2013 meeting:
- discussion of project goals
- 10 GHz and 10/24 GHz Rover Rig requirements
- 10 GHz components: LO, LNA, PA, Antenna, T/R, power supply
- Rover Platform (mechanical support) requirements
- Block Diagrams for 10, 24 and 10/24 GHz rigs
Please click here to view or download the project workshop slides from our May 2013 meeting:
- 24 GHz test results for surplus PCOM upconverter and downconverter modules
- 10 GHz surplus brick (from Harris DVM10) retuning to 10224 MHz LO
- 10/24 GHz dual band feed construction workshop
- notes on T/R sequencing requirements
Please click here to view or download a block diagram of the unmodified Harris DVM 10 surplus radios:
- several members have used these as a source of 10 GHz LO, filter, LNA and PA modules
- the diagram includes some useful signal gain and level specs for the modules.
Please click here to view or download W5LUA's paper on using the PCOM modules at 24 GHz.
Please click here to view or download AD6FP and AA6IW's MUD 2001 paper on the 10/24 GHz dual band dish feed horn that we are building.
Please click here to view or download the MUD 2012 paper that describes the 3744 to 144 MHz up/down converter that is shown as the first IF in this project's 10/24 GHz radio design.
Please click here to view or download AD6FP's MUD 2001 paper on the 10/24 GHz "flip switch" radio architecture that is the inspiration for our 10/24 radio.
The 2015 Officers and Board Members were elected in the February 2015 meeting
- President: Mike Lavelle (K6ML)
- Vice President: Bob Kraus (KK6PKL)
- Secretary: Brian Kline (WA6QDP)
- Treasurer: Jerome Peters (AF6UX)
- Board of directors:
Oliver Barrett (KB6BA)
Jim Moss (N9JIM)
Mike Stunes (KC0TQX)
Minutes from the February meeting
Jim Moss called the meeting to order at 7:08 PM.
The first order of business was the election of officers for 2015. The officers and board members are listed above.
That ended the formal portion of the meeting.
The informal meeting was a lengthy round table discussion of current activities and also a show-and-tell of several surplus items including power amplifiers and a small 10GHz patch antenna
Mike Lavelle discussed the possibility of a weekend open house at Allphone surplus.
This was to be followed by the second portion of Larry Zuckerman, K3LZ presentation on his recently patented novel "Post Generator Phase Noise Cancellation Technique" but we ran out of time so Larry will give this talk in the March meeting.
New! Documentation for Harris 10GHz surplus equipment
Mike Lavelle, K6ML and Oliver Barrett, KB6BA have provided us with much of the documentation for the surplus Harris DVM10 Digital Versitility Microwave radio links. Please log into the Members Only page to obtain two PDF files.
Improvement of the Stellex/Endwave YIG Synthesizer
by Jeffrey Pawlan, WA6KBL
The Stellex/Endwave mini-YIGs along with their phase locked synthesizer board are able to provide you with a stable and relatively low noise X-band signal source. However, they designed it incorrectly and most of the output power of the YIG is needlessly lost.
I have redesigned the sampling circuits so that you will now obtain +12dBm to +13.5dBm output power. It is an easy and inexpensive modification.
Because John Miles, KE5FX did the original work on using these surplus items and there are many links to his webpage, I have put my article along with nine photographs and figures on his webpage. Please click here to go to this page and then scroll down to nearly the bottom of that webpage.
Current Updated Rosters Available to Members
Members may obtain the rosters in several sort orders by logging into the Members Only webpage. These have not been updated because we did not receive updated memberforms or emails stating that your information has not changed. Also we need the dues from local members.
The presentation by Goran AD6IW on high efficiency amplifiers.
He gave at the 2010 EME conference and also at the 50MHz and Up meeting in Sept. Click here to download it
Report on the Ham Radio Social at the International Microwave Symposium on May 25, 2010 in Anaheim
The report and all photos are now located on a separate page. Please click here to view
Two presentations by Brian Yee W6BY are available for download
A slide presentation on an Introduction to Amateur Radio Microwave Operation is available as a PDF. Click here to download it
The second presentation is located on the Events tab page.
Microwave Beacons in operation UPDATED The following beacons are known to be operating as of 02-06-2015:
|Mt Vaca||CM88WJ||38 24.51, -122 06.50||10368.325||W6ASL||+?? dBm||??dBi omni||CW ID|
|Mt Allison||CM97BL||37 29.905, -121 52.206||10369.192||AD6FP||+17dBm||10 dBi omni||CW ID, drifts ~10 kHz|
|Mt Allison||CM97BL||37 29.905, -121 52.206||10369.225||AD6FP||+17dBm||10 dBi omni||Linear translator output is 11-55 kHz above beacon|
|Mt Allison||CM97BL||37 29.905, -121 52.206||10368.625||AD6FP||+17dBm||10 dBi omni||Linear translator input 600 kHz below desired output|
|Mt Allison||CM97BL||37 29.905, -121 52.206||24192.01||AD6FP||+?? dBm||??dBi omni||CW ID|
|Mt Allison||CM97BL||37 29.905, -121 52.206||47061.017||WA6QDP||+?? dBm||??dBi omni||CW ID|
|Mt Leeson||CM97AE||37 10.034, -121 55.500||10367.990||KF6KVG||+?? dBm||??dBi omni||FM ID, locked?|
|Mt Leeson||CM97AE||37 10.034, -121 55.500||24191.975||KF6KVG||+?? dBm||??dBi omni||FM ID, locked?|
|Mt Leeson||CM97AE||37 10.034, -121 55.500||47087.99||KF6KVG||+?? dBm||??dBi omni||FM ID, locked?|
|Mt Leeson||CM97AE||37 10.034, -121 55.500||79920||KF6KVG||+?? dBm||??dBi omni||FM ID, locked? antenna aimed towrds Portola Valley|
|Heaps Peak||DM14KF||?,?||10368.370||?||+?? dBm||??dBi omni||FM ID|
|Mt Frazier||DM04MS||?,?||10368.310||?||+?? dBm||??dBi omni||FM ID|
|Palos Verdes||DM03TS||?,?||10368.300||?||+?? dBm||??dBi omni||FM ID|
|Santiago||DM13FR||?,?||10368.330||?||+?? dBm||??dBi omni||FM ID|
|San Miguel||DM12MQ||?,?||10368.360||?||+?? dBm||??dBi omni||FM ID|