This post is cross-posted on my general-purpose blog, jeff.glass/blog
I mentioned in my Field Day post from a few weeks ago that I was hoping to get out to a Parks on the Air activation soon, and this past Saturday, I made it happen!
Parks on the Air is an international program inspired by the ARRL’s 2016 National Parks on the Air event. While that program ended at the beginning of 2017, a group of invested amateurs set about booting up an independent, ongoing program in the style of Summits on the Air, Islands on the Air, World Wide Flora and Fauna, etc. The program engages two (overlapping) sets of radio operators: ‘Activators’ who set up portable, temporary operations in state and national parks and wildlands, and ‘Hunters’ who seek them out on the air from more permanent setups. Of course, you can make ‘park to park’ contacts and be a hunter and an activator at the same time.
The draw of this for me is, as I alluded to in the Field Day post – I love the energy of being in the middle of a pile-up. Even if these contacts have a more lighthearted and friendly feel than a rapid fire contest, being a desirable contact on the air is a really jam.
After attending the South Milwaukee Amateur Radio Club’s swapmeet in the morning, I headed back south to Volo Bog State Natural Area, a wilderness preserve in Northern Illinois.
The park surrounds a large natural mashland, with many miles of a loop hiking path, scenic overlooks and, importantly for radio operations, a picnic area. I did some scouting on Google Maps ahead of time, and guessed that the picnic tables would be far enough apart that I could find a quiet corner to operate in.
And indeed, apart from a few hikers and what looked like a field-trip just departing, the park was pretty quiet. I found a nice picnic table in the shade next to the marsh to set myself up.
My setup for the day was somewhat more powerful than my Field day setup, including:
A Yaesu FT-891 running ~70W SSB on 20m and 15m, with the included microphone.
A Wolf River Coils TIA Mini-Mega antenna – in retrospect, I didn’t need to install the base-loading coil, since the 17′ whip is full size on 15m and 20m.
No tuner, but I did bring my Autek RF-1 to make sure the antenna was adjusted correctly for each band.
A little powerpole Power Analyzer to track power usage from the battery
My classic Hamkey iambic paddle on its little plastic base
A paper logbook
Oh what fun was had! I made 98 QSOs in roughly two hours of operating – all but 4 of which were on 20m, the last few on 15m. The bands were all over the place. I had wild swings of propagation into the eastern seaboard and the Southeast; at one point, I had five consecutive contacts from the same corner of Northwest Georgia. But I also reached some ears out in the Southwest, and even a handful of stations out in Oregon and Washington. I also made 8 (I believe) Park to Park contacts with other operators out the in wild.
All in all, a tremendous day of fun and excitement, and I’m looking forward to getting back on the air in a park soon.
This post is cross-posted to my general-purpose blog, jeff.glass/blog
Despite sunburns, shattered plastic, and a literal tornado warning, sunburns, I had a great time at Field Day 2021 this year.
My intention had been to head out to the northern Chicago suburbs on Saturday morning for some testing of the setup. My wife and I had purchased an annual pass to the Lake County dog parks in anticipation of the Fourth of July weekend, and our plan had been to drop her (and Winnifred, a very good dog) at one of these parks, go around the corner to a quieter, non-dog-filled local park, setup and operate for an hour and change, then pick the two of them up and head home. I’d charge my battery using an inverter in the car, grab some water and lunch at home, then be back out in a closer local park Saturday afternoon for a long operating session. And maybe, if I woke up in time, I’d pop back out in the morning to the park around the corner from my place for some grayline work on Sunday morning.
What Saturday should have looked like.
Chicago weather had other plans.
Tornado Warning including Chicago IL, Cicero IL, Berwyn IL until 12:15 PM CDT pic.twitter.com/v7zLSObdy5
We spent pretty much the entire day on Saturday huddled indoors against a pretty fearsome storm, which including multiple tornado warnings, thunderstorm wanrings, flash flood alerts… it was a wild day. I did make it out once in the afternoon to run to the hardware store to work on an impromptu Magnetic Loop antenna project (more on that soon), but other than that, we were holed up with our poor frightened dog.
At least we have a sense of humor about these things
But like a breath of fresh air, Sunday brought cool(ish) clear skies, dry weather, and a rather perfect operating day by mid-morning. So I pulled the portable-rig back together and headed out to the originally-planned local park to catch the last few hours of Field Day.
My setup’s changed a fair bit in the last couple years (and will likely be changing again soon). Here’s what I was playing with on Field Day this year:
Wolf River Coils “Mega Mini TIA” portable antenna, a stainless steel collapsible whip with a base-loading coil that sits on three removable tripod legs. WRC sells a wide variety of configurationsand sizes of this basic setup – mine is a 17′ whip with the larger (~14″) coil and 24″ tripod legs. It’ll tune around 80m to 10m, though of course on 80m it’s reeeeally short.
The antenna ships with three 10m radials, which attach to the tripod base with ring lugs. I added three 7.5m radials (1/4 wavelength on 30m) and re-used my 5m radials from the QRPGuys Tri-Band Vertical setup I had been using. Each set has a bullet connector on it, and a single ring-lug-to-three-bullet-connector squid attaches to the tripod
The battery for the day was a TalentCell 12V, 6A, 8300mAh battery i picked up from Amazon. We used these batteries all the time in live theatre for their size and weight, and while I doubt that I’m getting the full 8300mAh from it (especially since the X108-G draws around 6A on transmit), it lasted me through a solid afternoon’s operating.
I remounted my iambic paddles from their cast-iron base to a lighter plastic one
I picked up an Autek VA-1 antenna analyzer earlier this year, which makes a great quick tuning method for the antenna. I played around with bringing my Nano NVA H-4 out, but it’s just a little too fiddly for regular field use.
25′ of RG8x from the radio to the antenna
A camp chair and a portable picnic table make from easy ergonomic in the field
Logging is pen-and-paper, for now
The setup in the park
I spent the first couple hours hunting and pouncing, mostly on 20m with a stint up to 15m. 20m was super-densely populated as usual; 15 less so, but still with some decent stations holding the band down. I made roughly 25 contacts in that time with some decent distance – Arizona, Florida, Arkansas, Pennsylvania..
At 1pm local time, Field Day hit 24 hours elapsed, which is the maximum operating time for home, mobile, and emergency operations center stations… but Class A (club) and Class B (1/2 op portable) were permitted to go to 4pm. And with the bands newly clearly of the massive home stations, I figured, why not call CQ for awhile?
WHAT A RIDE.
I held a frequency on 20 meters for roughly 75 minutes, during which I made 90+ contacts. Being the run station was an absolute blast – I’ve done such things at Field Days before, but never as a solo operator and never with my own personal station. Knowing there’s no logger to have your bag, just you and the airwaves and the piles of people calling… a truly great time. I know I won’t set any records for speed or quantity of contacts, but I had a blast.
I’m currently looking for a day to go out and do a Parks on the Air activation to recapture some of the rush of running a station. Really, what a joy. And I’ll have a couple of new toys to play with by then…
There’s lots of Parks on the Air parks in the Chicagoland area – I hope to be activating them soon!
This post is cross-posted to my general blog, jeff.glass/blog
I went to the WCRA Hamfest in St. Charles this weekend in search of test gear (I had been fortunate to find a working Heathkit IM-2420 Frequency Counter there a couple years ago). I didn’t come away with anything of that sort, but I did scoop up this yellow beauty:
This beaut is a CDV-720 3A High Range Radiation Meter. It’s a remnant of the early cold war, the beginning of the atomic age – thousands were produced in the late fifties and early sixties by the Victoreen Company out of Cleveland Ohio. It’s got a cast aluminum case that feels like it’s made to survive a bomb, and maybe it was. The manual notes that:
It is designed to be used by radiological Civil Defense personnel in determining radioactive contamination levels that may result form an enemy attack or other nuclear disaster.
The really staggering thing about this meter is the range it covers: up to 500 Roentgens/hr. At that rate, your goose is cooked in a matter of minutes (first metaphorically, then literally).
Here’s a brief video overview of the meter, its circuitry, and the scary-high levels of radiation that it’s meant to measure:
With the 50W QRP amplifier project coming along nicely, I felt it was time to start thinking about a reproducible case for the project. And for custom, reproducible cases, 3D printing is my current tool of choice.
I ended up designing the case on a YouTube Livestream on Saturday night, to which a few great colleagues stopped by to ask questions and offer advice. The full video is below.
The case is in two parts – a box with standoffs for the PCB and holes for connectors, and a lid with labels. The standoffs and the attachment holes for the lid are meant to connect with M3 threaded-inserts and be held down with M3 machine screws.
This was my first time using Fusion 360’s Eagle Sync function – since Eagle was acquired by AutoDesk in 2016, it makes sense that they’ve been working to integrate PCB design workflows into their other products. The sync was fair straightforward – open Fusion360, select Eagle Sync, select your board file in Eagle, and after a minute or two of importing, up pops your PCB in Fusion360. Neat! I’m still struggling with how to handle board cutouts in eagle, and I’m not sure how well they’ll be supported in Fusion, but that’s a project for another day.
Here’s the final design as it turned out in Fusion360:
The PowerPole model was provided by Chris Wych, a theatrical propmaster who’s done some really interesting work with Fusion360, including using it to model some 2d-printable geodesic designs which then folded up into geometric shapes. Very cool!
First print of this design coming soon!
73
This post is cross-posted to my more general-purpose nerdery blog, jeff.glass/blog.
The 5W-to-50W QRP HF Amplifier project is rolling along nicely – I received the first PCB draft in the male this week and am 90% of the way through assembling it, with only heatsink-placement left to sort out.
I’ve made a couple of additions to the schematic since the original layout, including a relay-activated indicator (R27 and its LED) and an RF-output sensing LED (from C14 to its associated LED to ground) along the the lines of VK3YE’s recent project. There’s also a space on the PCB now for a low pass filter with the same footprint as Hans Summers’ LPFs over at QRP-Labs. Not that you’d necessarily want to reuse a QRP LPF for a 50W amp, you’d be in danger of putting too much voltage on the caps, but that would be a simple change.
Here’s the schematic as it exists now:
And here’s the current boards (layout, unpopulated, populated):
I’ve already got a little laundry list of things to modify for a second rev of this board, including, in no particular order:
Swap the Diode placements the vertical to preserve board space
Add footprints for alternate relay packages
Add footprints for alternate trim-pot packages
Re-think component designators for clarity
Add bypass jumpers for the 3dB input pad and the LPF.
For some reason, the none of the component values printed on the silkscreen, will need to sort that out
I’m not sure if I screwed up how to designate a cutout or if JLCPCB doesn’t do them for its bare-bones PCB service, but I’d like not to do the next set with a drill press and a nibbler.
Hoping to put this on the air soon for some signal tests. Hear you there!
73
This post is cross-posted to my more general-purpose nerdery blog, jeff.glass/blog.
This past weekend, I started on the process of laying out the 50W QRP Amplifier project as a PCB. Small PCBs can be remarkably inexpensive these days – $10-$15 for 5 pieces of say 4″x4″, shipped in 2-3 weeks. I’m treating this amplifier project as a chance to experiment with different, similar FETs to learn about critical power MOSFET properties, and also as an opportunity to brush up my layout skills that I haven’t used in awhile.
As the first step of PCB design, I captured the schematic of the amplifier as built in AutoDesk Eagle. I did this on a livestream on YouTube, the first time I’ve tried such a thing. It was great fun! Kenneth W6KWF stopped by to lend advice – he deals with prototype PCBs as part of his day job, though he has team members to do most of the actual layouts when needed. We’ve had a great deal of fun over the years, including building a cloud chamber for seeing charged ions in high school.
This post is cross-posted to my more general-purpose nerdery blog, jeff.glass/blog.
As I alluded to last week, I’ve been working on a simple “QRP Amplifier” to kick my power up from 5W to something a little more punchy. Specifically, an amp I can still use when portable. There’s something wonderful about achieving a contact with only 5W, but there’s also the frustration of getting into the field and having band conditions just wreck your day. It’d be nice to have the power to crank up the juice for special occasions.
While I have awhile to go before this project is wrapped up with a bow and ready for field use, here’s a brief video about my first successful test. 5W in, 50-60W out when run off two 13.8V sources in series:
More technical details to come, but for now, I consider this a really successful validation of the idea! Like I say, a few more critical steps to come, including an input 50-ohm pad, a low pass filter, and a case, but this is enough of a proof of concept to move forward.
This post is cross-posted to my more general-purpose nerdery blog, jeff.glass/blog.
Following the Forth of July, I took a few days off of work to recuperate from a grueling work project that we pushed over the finish line on the third. And what better way to relax in the wake of a heatwave than getting out in the beautiful, low-70’s weather and working on a new portable HF antenna.
From eBay listing
The heart of the antenna is an inexpensive ‘7.2m’ telescoping fishing pole, which can be had for less than $30 with Prime shipping or for less than $10 if you don’t mind waiting. The pole weighs about 10 ounces, comes with a small fabric sheath, and collapses down to about 24″. I’ve been wanting to try out something like this since I stumbled across VK3YE and his squid-pole setups awhile back – Peter’s also featured these particular poles in another video. Be aware, a pole called “7.2m” may not actually be 7.2 meters from end to end: check the listings carefully:
Note the difference between the “stretch” column and the “specification” column.
The length of the pole is enough for a quarter-wave vertical for 20m with some room to spare on either end. To allow for multi-band operation, I added a QRPGuys Tri-Band Vertical accessory to the bottom of the antenna. The piece is essentially just two loading-coils (in this case, iron-powder toroids) with slide-switches to short them out. The 20m configuration is a true quarter-wave vertical; one of the toroids is switched in series for 30m, and both are placed in series for 40m. Ultimately, not a complicated setup. While it would be easy enough to homebrew, the ergonomics of the switches, the hardware to attach the antenna wire and radials, and the clever PCB setup are enough to make it worth the $15 to just buy the darn thing. It even has little notches on the edges of the PCB for straps/ties/rubberbands to attach it to the vertical.
From QRPGuys.com
Tuning the antenna is straightforward: you cut a piece of wire (a bit long) for a 20m quarter-wave, and lay out four 10′ radials. Then, you bit-by-bit trim down the vertical element to resonate at the desired point in the 20m band. Then you switch in the 30m coil and compress/expand its turns without changing the antenna length to resonate on 30m. Finally, switch in both coils and adjust the second coil to resonate on 40m without changing either the antenna length or the first coil. Voila, a tri-band, base-loaded antenna.
Unfortunately, my antenna analyzer is old school, and doesn’t have a frequency readout. It’s an old MFJ-207 that I scooped up at the SMCC Hamfest in 2016, and while it does have a port to attach a portable frequency counter, I couldn’t find my cheapie one on the day. But I do have a nice Heathkit IM-2420 Frequency Counter with an internal OXCO that I scored an amazing deal on at a hamfest last year (it had an intermittent power switch). So, I attached the MFJ to the antenna, tuned its analog VFO for lowest SWR, walked inside without touching the dail and hooked it up to the frequency counter to see where the center frequency was. Repeat for say the upper and lower 2:1 SWR ranges. Trim the antenna a little, and repeat measurements. Once 20m is tuned, repeat with adjusting the coils for 30m and 40m. A fairly cumbersome process, but for three frequency ranges on one antenna, it was a half-hour project at most.
In the end, the antenna is less than 2:1 SWR across all of the 20m band, all of the 30m band, and all but the top 50 Khz of the 40m band.
I’ve glossed over the mechanical details of the antenna to this point – the base of the telescoping pole fits snugly-yet-easily into the a piece of 1″ schedule-40 PVC pipe. I bought a 5′ section from the local big-box store and cut off a ~10″ section to hold the antenna. I strapped two ground-stakes that I got at Hamvention this year to the bottom with a couple zip-ties and a couple rubber-bands. Finally, I threaded a long 3/8″ eye-bolt though a matching hole about 2″ from the bottom of the pipe and secured it with a nut on either side – this acts as both a stop for the pole so it doesn’t fall out the bottom, and provides an easy hand- or foot-hold for pressing the stakes into the ground.
The finished antenna mount. It may be getting a coat of high-vis paint in the near future.
The setup for the radials was something I stumbled across by chance while buying the PVC pipe. Our local big-box hardware store was having a sale on these RECOIL Brand cable winders that are meant for headphones or charging cables or similar. I’ve found that they can almost hold four 10′, 24-guage speaker wire radials. This is solving the problem of wires-getting-tangled-in-a-bag that I’ve had with all my antennas to date. Thank goodness!
A few loose ends are worth it for the assurance that the wires won’t get tangled in transit.
It takes about 6 minutes to setup or tear down the antenna:
The stakes are driven into the ground with a firm foot.
The telescoping pole is unwrapped and placed in the base
The antenna wire is unwound from the QRPGuys winder and tied to the tip of the telescoping pole with a small bit of cotton-wrapped nylon line (what we’d call tie line). The top section the pole is very flimsy, so I add a second tie to the next-largest section.
The pole is pushed up to full height, taking the antenna wire with it, which leaves the QRPGuys rig hanging about 2′ off the ground.
The QRPGuys rig is tied to the pole with another bit of tieline.
The radials are unstrung from their winder, pinched to the ground terminal on the QRPGuys rig, and spread out.
Run coax to a nearby table/seat/rock.
Set up radio, battery, key, antenna, and logbook.
The antenna fully set up and freestanding.
Of course, my very first time away from home with the antenna… I forgot the radial wires. D’oh! I was way out in the suburbs, too. I wasn’t about to drive an hour home and an hour back for 4 bits of wire, so I first tried out the antenna with no radials (just the coax as a counterpoise). This worked alright – I picked up K2D in CT in the 13 Colonies event on the second call (this at 5W QRP with the ATS-4), but was having trouble with other contacts.
Since I planned to swing by the local Fry’s Electronics on this adventure, I decided to pause operating for a while and make that run. Mostly I was picking up parts for an amplifier project (more on that to come), but while I was there, I looked for solutions to my radial problem. I found a 10′ section of RJ11 phone cord with 4 wires for $1.69 – perfect! Back out in a new park, I stripped the wires out of their jacket, spread them on the ground, and tied them to the antenna’s ground terminal. Instant radials!
And such colorful radials too!
With the antenna back to spec, things really picked up – surely, being on 20m at sundown didn’t hurt either. I scooped K2A (NY), K2B (VA), K2H (MA), K2L (SC), and K2M (PA), as well as the 13-cols bonus station WM3PEN in Philly. Many of these I got on the first or second call, though K2L was a real struggle. There was a very patient operator on the other end though.
The 13 Colonies special operating event runs each year for a week around the 4th of July in the US.
I picked up a couple of other interesting stations along the way: PJ2/KB7Q out of Curacao (though the license gives away that he’s either an ex-pat or visiting), and CQ918FWC from Madeira Island (!) off the coast of Portugal. There were a number of these World Cup special stations on the bands this week as we close in on the finals. At 3800+ miles away, this was my best DX of the day, and a great proof of concept for the new antenna.
At QRP wattage ,this 3800 mile contact was made at 760 miles/watt.
This post is cross-posted to my more general-purpose nerdery blog, jeff.glass/blog.
While I’m still exhausted from the travel and the good times, I wanted to put up a little note from this year’s Hamvention, the largest annual gathering of ham radio operators in North America. I only decided a week ago that I was going – I left Friday after work, drove 5 hours to Dayton OH (well, Xenia), and crashed at a hotel. Up bright and early, spent the day at the convention and checked out some local beer and grub in Dayton. Sunday, caught an early breakfest with some friends new and old, then got on the road back to Chicago. What a ride!
Hamvention is a great place for meeting the hams you’ve yet to meet, and seeing again those you already know. I spent most of Saturday hanging out with the Workbench crew, but I also ran into hams that I knew from elsewhere. Plus this guy, who falls into both categories:
It’s wild that 15 years after I accidentally introduced the future W6KWF to ham radio we hung out together at giant swapmeet in the middle of Ohio. Totally wild.
The flea market was certainly the biggest radio swapmeet I’ve ever been to – it’s probably bigger than that De Anza flea market by a good 300% – but it wasn’t all that special. I would say there was the usual assortment of used radios, test year, bits and parts, old tools… nothing super intriguing. Of course, I did get there on Saturday, so perhaps all the interesting things were just scooped on Friday.
It was neat to see a lot of the vendor products in person that I’d only heard about, but since I wasn’t in the market for anything in particular, I didn’t linger too long at any of the booths. Except Elecraft – those are some very, very attractive radios. I chatted with Wayne N6KR (one of Elecraft’s founders) for about 15 minutes about the KX2 and its SDR structure, which, not to be a fanboy, was pretty exciting.
In the end, I don’t know if I would go back the very next year – it was a really neat experience, and I’d go to see the people, but in this age of eBay, Amazon, and vendor websites, seeing everything in person and picking through the fleamarket feel just a little bit like a relic of the days when everything had to be done in person.
That said, I did find a few treasures… here’s this year’s haul:
Roughly from left to right:
Some panel-mount SMA connectors
An old automatic shutter trigger/timer
A tube of TFM-2LH Level 10 2Mhz-1000Mhz mixers from Minicircuits ($15 for 20, a steal!)
Six interesting potentiometers (dual with concentric controls or dual with concentric switch)
A bag of assorted HF/VHF H49 Crystals
An old Collins 250Khz crystal filter
A ZUMspot DMR hotspot/raspberry pi kit
A pair of QRP-Labs filters, both a low-pass and a bandpass filter for 40 meters.
Sometimes, you get back from a big trip or conference or meetup thinking Boy, am I worn out, I don’t need to do any more of that thing for awhile. This time, I came how itching to get back to work, revive some projects that had been dormant for awhile, and make things. So for that, at least, Hamvention 2018 was worth it.
As I’ve alluded to previously, I’m currently working on a BITX-style transceiver, using bi-directional termination insensitive amplifiers in the vein of N6QWs ZIA rig and N2CQR’s BITX DIGI-TIA, with the added challenge of implementing a variable-bandwidth crystal filter. In the process of putting this thing together, I’ve been learning about and experimenting with these so-called termination insensitive amplifiers, and I’ve put together a little video about their characteristics and uses:
This is my first foray into video-making, and I had a great time putting it together. Looking forward to making a few more down the road.
kk9jef 