☰ Rogue Valley Amateur Radio Club

January 2, 2020 Club Meeting

Thursday, January 2, 2020 at 7:00 PM Medford Police Department Community Room, 219 S. Ivy St., Medford, OR

Program: Using the GQRX Linux SDR display program on the Raspberry Pi 4. Are we there yet?, John Armstrong, KF7UMK

John will discuss the installation of GQRX on the Raspberry PI 4 computer. GQRX is an SDR interface program that will allow your RPI4 to control, process signals, listen, and display information from various different Software Defined Radios (SDRs). There will also be a demonstration using an RTL dongle as the receiver.

GQRX is an AM, FM and Single Side Band (SSB) software defined receiver implemented using GNU Radio and the Qt4 GUI toolkit. As a result it supports the Ettus USRP devices as well as OSMO SDR compatible radios (quite a few).

Biography: John Armstrong, KF7UMK is club secretary. He was instrumental in bringing HSMM / AREDN to the Rogue Valley, and enjoys computers and ham radio.

Announced in the January 2020 issue of The Repeater.

Meeting Notes

From the February 2020 issue of The Repeater.

2020-01-02 RVARC Meeting Minutes

7:00 pm Vice-president Scott Cummings, NA7OM, called the meeting to order and welcomed everyone. Attendance was about 20 persons.

Treasurer’s report: Mike, WB6FFC, reported bank balance of $4768.19 in checking, along with $150 of petty cash mostly from new club dues payments.

Scott instructed the Secretary & Treasurer to sort out the IRS Form 990 situation, where the local IRS office seems to have misplaced the form submission.

Regarding the Cascade Amateur Radio Enthusiasts (CARE) collaboration, Darrell, N7CZX, needs contacting in connection with the Dual-Membership fees and the 2019 Field Day cost share.

Scott mentioned that there is a world-wide DX contest in March, and he plans to be working it from the Philippines.

There is a general plea for more participation in Governance and Presentations. All are encouraged to run for office, or give talks about their activities and interests.

7:21pm Break for coffee, snacks & visiting.

8pm Presentation: Using the GQRX Linux SDR display program on the Raspberry Pi 4.

John, KF7UMK, showed that it was possible to install and run the SDR software GQRX on a Raspberry Pi 4 computer. The Linux operating system on the rpi was the 2019-07-10 version of raspbian-buster, which was the most recent at the time. Once the rpi was configured for locale, timezone, etc and to boot to the desktop, installation of the SDR software and all dependencies was as simple as running one install command from a terminal window:

sudo apt-get install gqrx-sdr

Installation took up about 600Mb more space on the uSDcard, and included gnuradio libraries and various sdr hardware drivers.

Then to get an optimized data-processing configuration, run

volk_profile

from the terminal window.

Now GQRX can be found as a sub-item in the ‘Internet’ item-list of the main menu. It was tested with a cheap DVB-TV dongle from NooElect, and with a 2048kHz sample rate, the rpi cpu usage was around 75% on all 4 cores, with a memory usage of under 500Mbytes. The cpu temperature remained under 50C with a passive heatsink attached. The setup did not crash or complain during the demonstration.

Success! Hopefully. But, there certainly could be issues with the particular SDR hardware you are using, for instance, the NooElect rtl2832U usb device needed to have a config file named rtlsdr.rules copied to the /etc/udev/rules.d folder so that type of USB dongle would be automatically recognized.

Overall, the system could be claimed to be workable. Perhaps we can try various other SDR hardware with this GQRX software, and share the results.

PS: GQRX author Alexandru Csete has mentioned that he is writing a replacement for GQRX, so we may look to that for future progress. No date for release though. Any current serious issues with GQRX will likely not be fixed.

References:

8:50pm End Presentation

Mention was made that Winter Field Day is coming up, January 25&26 2020

8:55pm meeting adjourned

John, KF7UMK, Secretary

Board Meeting

2020-01-07 RVARC Board Meeting Minutes

Attendance: Scott Cummings, NA7OM, Tom McDermott, N5EG, Pat Cunningham, KD7MPA, Mike Bach, WB6FFC John Armstrong, KF7UMK, Allan Taylor, K7GT.

7:00 pm called to order

Discussion about the apparent non-receipt of the 2019 IRS Form 990-N, that treasurer Mike had hand-delivered to the Medford IRS office.

It was also mentioned that there seems to be a gap in receipt of some prior year’s Form 990-N’s. The board will need to investigate.

Pat remarked that there appears to be a difference in our non-profit corporation type between the state and federal governments. The federal type is public benefit, consistent with our federal 501(c)3 status required by our Sept. 2000 governing Document, but the State of Oregon type is mutual benefit. The practical implications of this may also need to be investigated, but for now, no tax-deduction letters will be offered for donations.

Regarding RVARC’s collaboration with the CARE club, Darrell, N7CZX, needs to be contacted about dealing with their share of 2019 Field Day expenses and also accounting for the dual-membership fees between the clubs.

A point of information was that the RVARC fiscal year runs from Jun 1, through May 31, of the following year. This should be kept in mind regarding various form-filing deadlines.

Suggestions were offered for 2020 meeting program presentations, and the following list was proposed. Individual programs may need to be re-scheduled depending on circumstances.

  1. February – nanoVNA by Mike and Scott. Tom will also make a verbal request for programs during the February meeting– please tell us if you want to talk in the future, we can call you on the phone to discuss…
  2. March – My favorite DX tools & DX clusters – Scott Cummings.
  3. April – detailed N1MM+ - speaker or team needs to be recruited.
  4. May - WSJT-X either Pat Cunningham or John Laybourne
  5. June - SDR update. And Field Day planning.
  6. (6A) Swapmeet - date / time / place TBD. Mike may have a new parking lot available at Ave G & 11th street in White City (near Biomass). (6B) September - Smith Charts, S11/S21, etc. Tom McDermott
  7. October - Antenna measuring workshop VHF/UHF / nanoVNA. Bring your antennas.
  8. November – club elections. Book review of N6BT array of light / antenna physics. Allan Taylor.

— Other topics / backups –

  • Two meter SSB social event, bring latest ’toys’.
  • ESP8266 – Pat Cunningham.
  • Invite Jeff to present about restoring AM Broadcast transmitter.
  • Scott – Contesting / operating / Dxpedition from Palau.
  • Luke Bryan – repeater database / cell phone app. John Armstrong to contact and follow up.
  • Skype ?
  • TangerineSDR update?
  • Satnogs?

————–Final discussion items:

  • E-mail to Bill Anderson declining tax letter. Refer him to JC-ARES?
  • Discussion of folks willing to run for president in 2021.

8:53pm Adjourned .

John, KF7UMK, Secretary.

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