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the Tuneup and rig testing July 2016

Our annual picnic was July 9 at Ed Levin Park in Milpitas. Approximately 20 folks attended. Thanks to David and Larry for organizing the BBQ takeout from Armadillo Willy's. Thanks also to David and John for the photos.
tuneup1 2016
Setting up for the 2016 tuneup

tuneup2 2016
Ten rigs on the firing line: KI6CLA, W6DXJ, K6TJ, W6BY, W6TCP, K6ML, AD6FP, K6OJM, KB6BA, WA6QDP

We had 10 rigs in the tuneup (10 on 10 GHz, 2 on 24 GHz), including a number of new rigs. Thanks to Gary and Mike for organizing the tuneup.
We had a little trouble with the MDS test signal generator and we had to improvise a substitute generator using a 2M FM HT and a stack of SMA fixed attenuators (thanks, David!).
As a result, the MDS results are not absolute values and cannot be compared to last year's calibrated results, but they can be used for relative comparisons between the ten rigs.
We also had some trouble again with 24 GHz testing... we will see what can be done over the winter to improve next time.
Brian (WA6QDP) and Pete (W6DXJ) tied for the strongest ERP. Pete had the best MDS. Full results are in the ERP and MDS results files [links to the ERP and MDS files], sorted by decreasing measured effective radiated power (ERP) and increasing minimum detectable signal (MDS).
I suggest that you look at the ERP results file first.

Possible reasons for an ERP shortfall include:
It's helpful to compare yourself to similar rigs. For example, we had three 18" dishes with 1W (+30 dBm) PAs which should all have delivered +60.8 dBm ERP. One was within 0.3 dB, the other two were low by 6 to 8 dB.
Next, look at the MDS results file. These list:
As already mentioned, many MDS impairments are shared with ERP (feed, feedline, pointing, etc), but there are some others unique to MDS: the system noise figure and the effective receive bandwidth.
The noise figure can be degraded by a poor LNA noise figure, additional losses in the T/R switch or between the T/R switch and LNA, or by not having enough LNA gain to swamp the noise levels of subsequent stages (filters, mixer conversion loss, IF noise, etc).
The effective receive bandwidth is a real wildcard... each unit under test probably had a different IF filter bandwidth (from 100's to 1000's of Hz, a 10 dB variation) and different operators. The "grey matter" filtering in the operators' heads can add or subtract on the order of 10 dB MDS... Finally, the definition of "minimum detectable" is subjective... some folks are more aggressive than others.
So, take the results with a grain of salt and try to adjust them up or down based on these factors. Also, recall that due to our testing problems this year, MDS results are relative only, not absolute.
I hope the tests are helpful and that you had fun seeing others' rigs and chatting at the picnic.
Here are the documents to download:
Please click here to view or download 50upTuneup160709-mds
Please click here to view or download 50upTuneup160709-erp
See you on the microwaves!
more photos coming soon

Older Documents and Presentations


David Combs and Regol Instruments
2013 10/24 GHz club project documents
a block diagram of the unmodified Harris DVM 10 surplus radios
W5LUA's paper on using the PCOM modules at 24 GHz
AD6FP and AA6IW's 10/24 GHz dual band dish feed
KK6MK AA6IW 3600 MHz Synthesizer and Mixer
AD6FP 10/24 GHz "flip switch" radio architecture
Brian Yee W6BY on an Introduction to Amateur Radio Microwave Operation
Documentation for Harris 10GHz surplus equipment
Improvement of the Stellex/Endwave YIG Synthesizer
presentation by Goran AD6IW on high efficiency amplifiers
the Ham Radio Social at the 2010 International Microwave Symposium
Spectrum Analyzers by Brian Yee W6BY
Build your own waveguide to coax transitions
Will Jensby Receives Lifetime Achievement Award
Record breaking 10Ghz WeekendM
Global Navigation Satellite Systems Update by W6RXQ (PowerPint preo)
Feb 07 Meeting Presentation
Filter Software Available for Download
24GHz Power Point pres
First QSOs via the Moon on 47 GHz
47GHz WOrld Record (October 30, 2005)
August 2004 Microwave Tune-Up Party Summary


David Combs and Regol Instruments


They demonstrated some test equipment and how to make microwave measurements. Here is a PDF of many of the masurements:
Please click here to view or download Advanced RF Tips and Tricks



2013 10/24 GHz club project documents

Group Project Notes: Building 10 and 24 GHz Radios

In 2013, we launched a Group project with two goals:
- help microwave newcomers to build their first 10 GHz radio
- help Group members to build a dual band (10/24 GHz) radio
Please click here to view or download the Group project presentation/workshops file Roadmap to 10 and 24 GHz.pdf
- 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.


A slide presentation by Brian Yee W6BY on an Introduction to Amateur Radio Microwave Operation is available for download as a PDF

Click here to download it

Documentation for Harris 10GHz surplus equipment


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.

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

A slide presentation on Spectrum Analyzers by Brian Yee W6BY. click here to download this PDF

Build your own Waveguide to Coax Transitions We have received written permission to post a published article from Applied Microwaves & Wireless Magazine (long-gone and is now High Frequency Electronics) that appeared in the Feb 2001 issue. The article is by Richard Kurzrok and gives you all the machining dimensions you will need to make a transition for a ny waveguide band from WR229 through WR42. These include the exact tuning screw placements. Click here to get the article as a PDF

Will Jensby Will Jensby Receives Lifetime Achievement Award During the September 2007 meeting, Will Jensby (W0EOM) was presented the 50Mhz and Up Lifetime Achievement Award by Brian Yee (W6BY) and Goran Popovic (AD6IW) for his achievements on the microwave bands.

Some of these achievements include records on 47, 75, 120 and 122Ghz bands. He has helped other Hams get onto higher frequencies, especially 24 and 47Ghz.

Congratulations Will!

Photo. From left to right: Goran, Will and Brian.

Record Breaking 10GHz Weekend This weekend Miguel W6YLZ, Dan K6NKC, and Bernardo XE2HWB and I participated in the ARRL 10GHz and Up Cumulative contest from Baja California, Mexico, operating at two spots along the Baja Sur (south) coast. Miguel, Dan and Bernardo set-up on the Vizcaino Peninsula in DL27, while I continued another 430km down the Baja coast to the small town of Puerto San Carlos in DL34wt.

San Carlos sits at the tip of a western bulge in the Baja Peninsula and has been visited by hams before, including Jack N6XQ and Chip N6CA who reported the reception of both two meter amateur and commercial FM stations during their visits there back in the mid 90s. Jack later returned with 10GHz gear and attempted to work an 800 mile path up the coast to Chip N6CA, Dave K6OW and myself set-up near Santa Barbara. 10GHz signals were not heard that day, but Jack worked Santa Barbara on 2meters which sparked this ham's interest in the path.

Now, more than ten years later, I visited San Carlos during the August microwave contest weekend hoping we could connect with one of the dozens of stations out in the field. It turned out to be a record breaking day and a half on 10GHz.

I made 53 10GHz contacts from DL34wt this weekend. The longest contacts were with Gary AD6FP at 1460km, then with N6CA and KH6WZ who were just a little closer in at 1448km. In fact, the NA 10GHz DX record was broken five times during the weekend, first by W6QIW at 1315km; then by N6CA and KH6WZ at 1320km, 1426km and again at 1448km; and finally on 8/19/2007 at 0845 with Gary AD6FP operating at CM96wa at 1460km (907mi) which should be the new NA 10GHz record. The AVERAGE contact distance for all 53 contacts was 1178km and the accumulated score on just two log pages is over 65k points!

I want to thank everyone who supported this effort, including the San Bernardino Microwave Society members who went out to the coast and into the hills, the fellows from the 50MHz and Up group in Northern California who came down and added to the success, to the hams who checked in with Miguel and myself on the hour on 40meters during the long trip down and back, and to our Mexican compadres Bernardo, Antonio and Dr. Levy of the FMRE. This was a group effort with shared rewards. My greatest pleasure comes from the participation and support we received from so many. Thank you all.

I encourage those who participated in this fun weekend to share here on the reflectors their recollections of these long contacts we made and see that your longer contacts get into the record book with sufficient details.

See you on the air,
Frank WB6CWN / 4C2WH

W6RXQ - Power Point "Global Navigation Satellite Systems Update" The power point presentation from our September 2007 meeting is available on the members only site here.

Power Point Presentation from February Meeting The power point presentation from our February 2007 meeting is available here.

Filter Software available for Download Dionysus a program that synthesizes, edits, analyzes, and joins filter circuits from audio to microwave frequencies. DIONYSUS is capable of designing from many different transfer functions, including Bessel, Gaussian, Butterworth, Tchebychev, Elliptic, and Pole Placed. ComNav Engineering has given us the right to distribute copies of the filter development software on this site for free! The version here has been updated to the latest one. Download it Here.... Submitted by: Jeffrey WA6KBL

24 Ghz Power Point Presentation available for download To download the 24Ghz Power Point Presentation, click here.

Announcement of the first QSOs via the moon on 47 GHz April 16, 2005 - The team of RW3BP, AD6FP, W5LUA, and VE4MA would like to announce that the first 47 GHz contacts via the moon have been completed. As you may recall, RW3BP heard the first lunar echoes on 47 GHz back in August of 2004. At that time he was heard by AD6FP, W5LUA, VE4MA and VE7CLD. Since the receipt of the first 47 GHz echoes via the moon, numerous tests between RW3BP and AD6FP led to improvements by RW3BP allowing him to copy calls from the lower power signal of AD6FP in January of 2005.

As of April 16, 2005 the team of AD6FP, W5LUA and VE4MA have each completed a CW QSO via the moon with RW3BP.

The station at RW3BP consists of a 2.4M offset fed dish and 100 plus watts while the station at AD6FP consists of a 1.8M offset fed dish and 30 watts. At W5LUA and VE4MA 2.4M offset fed dishes and 30 watt TWTs were used. Noise figures of all stations are in the 3.5 to 4.7 dB range.

Since the doppler shift can be as much as 100 + kHz at 47 GHz, one must continuously adjust the receive frequency to keep the station centered in the passband. Precision frequency control was obtained by using GPS controlled, Rubidium locked, or TV sync controlled phase locked local oscillators. Various techniques were in use to keep the Doppler shifted frequency in the passband of the receivers.

Submitted by RW3BP, AD6FP, W5LUA and VE4MA

47GHz World Record (October 30, 2005) On the evening of October 30 W6QI and AD6FP completed a 47 GHz contact over a 343 Km path, 30 Km farther than the current record. W6QI operated from Frazier Mountain DM04ms North of Los Angeles. AD6FP operated from Pilot Peak DM07bs near the northern entrance to Yosemite. The path is near line-of-sight with an obstructing peak about 20 Km south of Pilot Peak.

Signal levels were easy copy with some slow fading, 30+db margin on the Frazier end and 6+ db on the Pilot end.

Weather conditions were seasonal normal for California, temperatures in the mid 40 fahrenheit range with ~ 60% relative humidity. Both Frank and Gary were returning from the Microwave Update 2005 conference that was held in Los Angeles and hosted by the San Bernardino Microwave Society. The stations used were the same as last time:

AA6IW had another 47 GHz radio on the Frazier end with W6QI but due to local oscillator problems was not able to participate in the record breaking contact. N2MJI accompanied AD6FP to the Pilot end and assisted in the navigation to the site and the radio setup which were both done after sunset thanks to a flat tire on the way to Pilot. It took several hours to finally make the QSO due to problems at both ends: failing power inverter, failing local oscillator, aiming in the dark etc.

QSOs were also completed on 10 and 24 GHz with very strong signal levels and 10 GHz was used as the liaison frequency. To assist aiming W6QI played back his 47 GHz audio to AD6FP over the 10 GHz liaison allowing AD6FP to do the final peaking of the dish. Signal margins indicate longer paths are possible but further attempts will have to wait for spring .

August 2004 Microwave Tune-Up Party Summary

Check out the pictures from the microwave tune-up party we held on August 7, 2004. We had a very nice day out in the warm summer sunshine, testing radios and ragchewing. We had a whopping 19 group members show up for the event!
click on this photo to view all. Tune-up Party Pictures