Gary @N8DMT
n8dmt.mastodon.radio.ap.brid.gy
Gary @N8DMT
@n8dmt.mastodon.radio.ap.brid.gy
Amateur Radio Extra, Maker, Product developer, Wireless/RF/Antenna guru / electronics consultant, LabVIEW, RTL-SDR, ADALM Pluto, GNU Radio, FCC testing. Location […]

🌉 bridged from https://mastodon.radio/@n8dmt on the fediverse by https://fed.brid.gy/
Cold WX stay-home activity: Successfully repaired my Chameleon F-Loop3 tuning capacitor (to remove intermittent shorts) and restoring TX operation on 40 meters. More evening CW fun ahead! Details and more photos at the QSL.net blog.
#hamradio #antennarepair […]

[Original post on mastodon.radio]
January 23, 2026 at 8:31 PM
Review of the Fluke 1953A counter/timer shows it is fully working as hoped (operating under local and remote control.) Verified all inputs and operations via GPIB remote control with a simple LabVIEW program. Have a few more esoteric tests to run in near […]

[Original post on mastodon.radio]
January 7, 2026 at 8:00 PM
What to do with an old Ubiquiti AirView2 USB spectrum analyzer when the software won’t run on Win10 or later PC? Answer: Write a LabVIEW program to read/display the raw serial data to keep using it for 2.4 GHz spectral occupancy and channel power info. Plan to […]

[Original post on mastodon.radio]
January 7, 2026 at 3:56 PM
Slow work day = A few moments to work on 2026 goal to make the lab a little better everyday. Today’s task is to add crimped connector shrink sleeving and a length marker to this Pasternack RG-58 C/U cable. Luckily it has a SMA on one end to slip the shrink […]

[Original post on mastodon.radio]
January 6, 2026 at 2:37 PM
Was able to measure the output 1 dB compression point for the QB-150 RF amplifier (with 12V supply). Kept it simple and just measured at 100 MHz as approximation for full frequency range from HF up to VHF band. Have been looking into how to measure across […]

[Original post on mastodon.radio]
January 5, 2026 at 8:06 PM
Have you noticed that some types of test equipment have gotten much smaller than the rack or half rack width instruments of the past? I am transitioning towards tiny-instruments and downsizing my home lab (having moved multiple times recently). Latest acquisition is a TinyGTC GPSDO timer counter […]
Original post on mastodon.radio
mastodon.radio
December 29, 2025 at 5:34 PM
Get going with FreeDV on HF, without fears or tears - The time has come for digital voice on the HF bands by Peter Marks VK3TP. (Found this linked from Peter’s blog on blogs.radio.)
#hamradio

https://www.wia.org.au/members/armag/2025/november/documents/AR%20Issue%206-2026_pp42-48_2.pdf
December 28, 2025 at 2:37 PM
December 27, 2025 at 2:26 PM
First (easy) test of the QB-150 Amps: Does the one with the top installed work? Answer: Yes! Measured 12.6 K Ohm on the power pin to GND. Applied 12.2VDC, measured ~120 mA current draw. Tested with NanoVNA-H4 with 40 dB pad on input side and found it has ~ +24 […]

[Original post on mastodon.radio]
December 21, 2025 at 9:34 PM
Reposted by Gary @N8DMT
I'm reading a 1974 issue of _Electronics Design_, and I'm amazed by all the cool new stuff. There are a bunch of things I want to order, but unfortunately they don't give any URLs.
December 21, 2025 at 8:49 AM
Repair RF Amplifier Project: With some time off ahead, dug out the box of Q-Bit QB-150 RF amplifiers. Likely these are all toast, but will test and troubleshoot to confirm. (These were pulls from a field HF antenna system that occasionally had lightning […]

[Original post on mastodon.radio]
December 20, 2025 at 8:46 PM
Slow work day = time for RF fun! Remeasured the Copper Mountain Technologies R54 vector impedance probe output signal characteristics to understand if it always used a fundamental output (or if it relies on harmonics like the NanoVNA-H4). TLDR: the much more […]

[Original post on mastodon.radio]
December 19, 2025 at 4:12 PM
Home Handyperson: Had a complaint from a family member that they were not feeling well when the dryer was running. Found multiple issues with the vent: 1) clamp was loose, vent pipe had two large slits cut into it that were leaking. Cut off the hack-job, fixed […]

[Original post on mastodon.radio]
December 13, 2025 at 5:14 PM
Ten Meters is just opening up here in EN52 Chicagoland, and seeing some single and double hop skip to the southeast. Going to be an interesting day!
#hamradio #10meters #magneticloop
December 12, 2025 at 2:34 PM
Made some progress on the low-cost noise figure & gain measurement setup, and have it running pretty well at 440 MHz. Have pages of notes and pictures to put together a how-to post or web page. Still need to check calibration at other frequencies, but […]

[Original post on mastodon.radio]
December 11, 2025 at 8:55 PM
#patchtuesday yields #waitwedneday: Started a “how long will it run” test with the BougeRV cooler powered by a new Anker Solix C300X DC power pack. With 12V @ 50W consumed during cool down, the run time estimate is almost 6 hours. With cool down completed, the […]

[Original post on mastodon.radio]
December 10, 2025 at 1:22 PM
Finished a first draft for my qsl.net web page documenting a low-cost DIY RF Noise Source suitable for making noise figure measurements under automatic program control (with SATSAGEN software). Still have a few more updates to the web page, but completed […]

[Original post on mastodon.radio]
December 8, 2025 at 1:13 AM
US Coast Guard aircraft executing a search just south of Key West Florida. Additional assets joining in now.
December 6, 2025 at 1:22 PM
What is inside a Mini-Circuits ZFL-2000 RF Amplifier? Had a few minutes to take a quick look inside one of these RF Amps. Didn’t learn much, and was surprised to see a fully-cased (pins) amplifier module inside. Would take a lot more effort to disassemble […]

[Original post on mastodon.radio]
December 5, 2025 at 1:59 PM
Reposted by Gary @N8DMT
4 General upgrades and 3 new Technicians. Not bad for an after Thanksgiving session. #HamRadio.
November 29, 2025 at 7:57 PM
Looking over Black Friday announcements from HRO and DX Engineering yields an interesting takeaway: today’s “super-specials” look a lot like last year’s everyday prices for many items. Anyone else seeing this too? #hamradio #blackfriday
November 28, 2025 at 4:12 PM