Category Archives: Homebrew

Field Reports, Homebrew, News, Portable, POTA, QRP, QRP Radios

Dave’s Minimalist Adventure: Homebrew POTA Activation in Dodge Brook State Forest

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Many thanks to Dave (K1SWL) who shares the following field report:

A Bare-bones POTA Outing

by Dave Benson (K1SWL)

It started with a one-of-a-kind homebrew project and mushroomed from there.  I was returning to my roots with a Direct-conversion rig and it hooked me in our recent ARRL Field Day event in June.

It acquitted itself well on 40M with a total of 81 contacts.

I’ve been enjoying operating various flavors of this design since then, and the bulk of it on 20M.  It finally occurred to me to take this project to the Field.   An impromptu POTA outing was born.

Dodge Brook State Forest (US-4897), is 25 minutes from here and features a clearing about 250 feet across surrounded by tall pines.  This ‘log yard’ was the collection point for logged timber some time ago.

I was able to select an operating location with an open shot to the Southwest from here in New Hampshire.

A homebrew pneumatic launcher put a support line up at 60 feet. [My throwing arm is only a fond memory at this point.]  The antenna followed- a PAR End-fed Half-wave.  The top wound up at the 45 foot level- limited by my coax length. The antenna was set up as a sloper favoring the Eastern US.

The choice of the operating position itself was more difficult.  A fine early Autumn day meant 80F and cloudless weather. Do-able, but toasty after a while.

I had a table and chair in the truck, but they’re a bit unwieldy.  A peek into the tree line yielded another possibility: rocks.   We have an abundance of those here in New England- souvenirs of recent glaciation.   I’ve also bushwhacked to SOTA locations in the past, and sometimes a downed log serves as an operating position.  I’m not proud.

I set the station up on a computer mouse pad to protect it and away I went- about a half-hour behind schedule.  I knocked off the requisite 10 contacts on 20M  in 13 minutes.

I had about 30 minutes available and finished the POTA session with 20 contacts.

This corresponded with the start of the Wednesday CW Ops Sprint activity and its high-speed cacophony.  Five more quick contacts there and I needed to break down the setup and head for home.  I was happy- something of a milestone!

The closeup shows the rig- it runs a generous 5 watts, and the 40M version is pictured.  This was shot in overcast daylight to avoid shadows.  This is board-only at present.

George-N2APB- is currently designing a companion enclosure for it. It’ll appear imminently on his website:

http://midnightdesignsolutions.com

Equipment Lineup:

  • ‘Old Friend’ Direct Conversion transceiver
  • Bienno 4.5 A-H LiFePO4 battery
  • Panasonic ‘over the ear’ headphones
  • Begali ‘Expedition’ model
  • PAR EF-20 half-wave antenna
  • RG8X Coax, 25 feet
  • Pneumatic Launcher, homebrew and 12V compressor.
  • ARRL ‘Minilog’ Logbook
  • Rocks
Field Reports, Homebrew, Morse Code, News, Portable, POTA, QRP, QRP Radios, Videos

QRP POTA: Pairing N3CZ’s Homebrew Transceiver with the TennTennas 49:1 EFHW!

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On Monday, September 2, 2024, my good friend Vlado (N3CZ) and I spent Labor Day morning playing POTA.

Our first activation was at Lake James State Park, using the new CFT1 QRP transceiver. It was a lot of fun–you can read the field report and watch the video by clicking here.

For the second activation, I wanted to take Vlado to a site I’ve activated numerous times—one of my favorites—that he had yet to visit:

Table Rock State Fish Hatchery (US-8012)

We arrived on-site around 11:00 AM and, no surprise, had the place to ourselves. Honestly, I was hoping we’d see the three dogs that often pop by for a visit, but I believe they were on vacation with everyone else!

We both figured 20 meters would be our bread-and-butter band for this activation. More importantly, our transceiver was a 20-meter monoband (more on that below), so I deployed my new 20-meter end-fed half-wave antenna.

This particular EFHW is built on a  transformer by Walter (NE4TN) at TennTennas.

TennTennas 49:1 QRP Transformer

I may have mentioned before that Walter gave me this little 49:1 transformer at Hamvention this year when I met him in person. Walter is one of my top hunters in POTA, and I can often count on hearing his call when I’m on 40 meters.

Walter handed me this little transformer as a thank you, with no obligation to promote it—in fact, he didn’t even tell me where they could be purchased.

But I’m a sucker for home-grown mom-and-pop ham radio businesses, so of course, I’m going to plug it! He sells these on eBay (partnership link) for $39 each as a small side business. Not a bad price for a solid little 49:1!

As I mentioned, I trimmed this one for 20 meters, but I’ll likely make it a linked antenna with 30 and/or 40 meters as well someday.

Vlado’s Homebrew Transceiver

I was also excited that Vlado brought along his homebrew 20-meter QRP transceiver.

I had seen this radio in his shack during various stages of development, but I had never had an opportunity to use it in the field.

I’m not sure if Vlado had used it for a POTA activation yet, in fact.

His little transceiver is super simple but sports proper filtering, an OLED display, and, despite the large battery he connected to it, has modest power requirements.

He built it into an old Kenwood VHF radio chassis he found at a hamfest. I’ve been with Vlado before when he’s hunted for chassis for his various homebrew projects. The OM is always building or repairing something in his shack.

We were really looking forward to putting this little transceiver on the air!

Gear

Note: All Amazon, CW Morse, ABR, Chelegance, eBay, and Radioddity links are affiliate links that support QRPer.com at no cost to you.

On The Air

As with our first activation that day, we decided to take turns with one radio instead of setting up two stations. Vlado was the first op to start calling CQ POTA! Continue reading QRP POTA: Pairing N3CZ’s Homebrew Transceiver with the TennTennas 49:1 EFHW! →

Field Reports, Guest Posts, Homebrew, News, Portable, POTA, QRP, QRP Radios, Travel

WN5C: Notes from a homebrew POTA adventure

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Many thanks to Sam (WN5C) who shares the following guest post:

Notes from a homebrew POTA adventure

Sam (WN5C)

I recently wrote about the homebrew transceiver I built to operate on a month-long trip through the American Southwest. Upon arriving back in Oklahoma here’s the final outcome: 27 days, 40 parks, and 669 QSOs. I honestly can’t believe that the rig went the distance, or that I made so many contacts on 2 watts or less!

The priority of this trip wasn’t radio, though. I’m an archaeologist and I’m starting a new research project that marries my historical interests with my love of two-way communication. In short, I’m studying the effects of how communication technology aided the American colonization and transformation of the western United States around the turn of the twentieth century. This means I walked and mapped single-wire telephone lines strung up in pine trees in northern New Mexico (used to connect fire lookouts with Forest Service ranger stations), a fascinating story of dramatic changes in land management. I also visited heliograph (sun-mirror signaling) stations established in southeastern Arizona by the U.S. Army Signal Corps in 1886 to assist in apprehending Geronimo.

Working Fort Bowie NHS (US-0815) in Arizona. The peak in the distance, Helen’s Dome, had a heliograph station on top. From the fort telegraph lines would have connected remote operations to the rest of the Army’s 1880s communication network. Next time I’m climbing up on top!

I look forward to relocating and studying the artifacts from more of these heliograph sites (mostly on remote peaks) to reconstruct this communication network and understand the lives of both the soldiers and the Apache, and how this novel surveillance system altered the battlefield. Based on the artifacts I’ve seen so far there are many cans of Army-issued proto-Spam and beer bottles surrounding the signaling station where American Morse Code would have been sent and received via flashes of sunlight. The original Field Day?

But back to radio. I covered a lot of ground and activated parks in Oklahoma, Texas, New Mexico, Arizona, Utah, Colorado, and Kansas.

The POTA sites that I activated (click image to enlarge).

At some locations I was camping so I was able to do multiple long activations and work the lower bands well into the evening. These were some of my favorite moments of the trip, being the only spot on the POTA app and leisurely working with no time or weather-based worries. It also gave me a chance to hear callsigns I was unfamiliar with, essentially exploring a new area of the country.

Working closer states after hours on 30 and 40 meters at Colorado NM (US-0918).

For other times, due to time constraints or weather (thunderstorms or that it was unbearably hot), I got my 10 contacts and moved on. Sometimes I packed the equipment for a long hike, often carried it from the car to a picnic table, and a few times deployed my antenna and operated from my vehicle.

Not every activation was a grand adventure. Sometimes, like here at Rocky Mountain Arsenal NWR (US-0226) in Colorado, I worked from the passenger seat in the car.

Every activation was memorable in its own way. I worked folks from 44 states, five Canadian provinces, and an unforgettable contact from Italy.

A map of the contacts I made (not including those in northern British Columbia, Alaska, and Italy).

The radio held up surprisingly well. Aside from it looking like a Dalí painting as the 3D printed box continued to deform in the heat, and some hot glue remelting, the electronic components worked as they should. I look forward to printing a stronger case and making some upgrades going into the fall. I do now have a real respect for the engineering that goes into designing field radios, especially those that are thrown into a pack!

Setting up a portable shack on Vail Pass in the White River NF in Colorado (US-4410). This was near the end of the trip, the plastic case was looking pretty bad.

After I began feeling less anxious about the homebrew radio (it kept turning on!) I could start focusing on the trip itself: an amazing POTA adventure with an often-uncooperative sun. Here’s a few themes I noted. Continue reading WN5C: Notes from a homebrew POTA adventure →

Field Radio Kits, Guest Posts, Homebrew, How To, Kits, News, Portable, QRP, QRP Radios

Field Radio Kit Gallery: KD0FNR’s Rockmite 20 and Tuna Topper

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Many thanks to Hamilton (KD0FNR) who shares the following article about his portable field radio kit which will be featured on our Field Kit Gallery page. If you would like to share your field kit with the QRPer community, read this post.

Rockmite 20 and Tuna Topper Pack QRP Punch

by Hamilton (KD0FNR)

Our ham radio field kit—in my mind—revolves around simplicity. I’ll walk you through a lot of details, because we have a blast with the field kit and I love talking about it. At the end of the day, it’s a kit radio and amplifier housed in a couple of cans with lengths of wire we bought at a hardware store for an antenna, a cell phone power brick, and a keyer glued together out of video game switches and an old battery case. We’ve thrown the kit into cloth shopping bags and backpacks with equal measures of success. We once patched an antenna connection using washi tape.

OK, I said ‘our’ and ‘we’, but who are we? I’m the dad of three kids—one of whom recently passed her Technician radio exam, KO6BTY—who are 12, 11, and 8 years old. Right now, they’re rarely on the radio—of course, that’s about to change—they help with most aspects of our radio outings.

Which brings up the question, what do our radio outings look like? Our outings are pretty equally divided between, camping and day trips. Our entire family has enjoyed camping—and done a lot of it—since long before I got back into ham radio. Each of the kids went on their first camping trip when they were a few weeks old.  Our camping trips range from local, public transit enabled outings—we take the bus to Pantol Campground, across the Golden Gate Bridge from San Francisco where there are two POTAs readily available: Mt. Tamalpais State Park and  Muir Woods. We also take multi-day/week trips: I grew up in New Mexico, so the kids and I frequently find ourselves back there activating or attempting to activate sites like Villa Nueva State Park, Organ Mountains National Monument, and Cibola National Forest, among others. These are the outings that have led to large-ish battery selections you’ll see below.

Our day trips are quick runs along various local bus, train, and ferry lines with a hike tacked on the end. Within the peninsula that encloses San Francisco, we have several POTA locations and two easily reachable SOTA locations. We pretty frequently bus to a spot, and then spend a few hours hanging out in a nice park getting some radio time.

Having said all of that, you might have guessed that our kit would be optimized for easy travel. You’d be right. Now, finally, let’s talk about the kit!

Radio Details:

All of our equipment is home-built. It’s evolved over the last year-and-a-half into he tidy kit you see above. Finally having a ‘typical’ kit picture is actually what inspired this article.

Equipment List:

[Please note: All Amazon links are affiliate and support QRPer.com.]

  • Rockmite 20
  • Tuna Topper
  • One 20 ounce can Dole Pineapple Slices (emptied—see support crew; and cleaned)
  • Two RJ-45 breakout boards
  • One spool butcher’s twine (two if you’re feeling bougie)
  • One Imuto power brick that supplies 15 V when funneled through:
  • One Adafruit USB Type C Power Delivery Dummy Breakout – I2C or Fixed – HUSB238
  • Two banana jack sockets (plus a few more for spares)
  • Forty feet 12 gauge insulated/stranded wire
  • Twenty-five feet (or so) RJ-45 Ethernet cable (scavenged from the parts bin at our local maker space)
  • One antenna launcher (scavenged from available fallen tree limbs onsite)
  • One donut Bag from your favorite donut store
  • One roll of washi tape

The Rockmite is a rock-locked radio with two available frequencies that are 500 Hz apart from each other. That makes our antenna design really simple; we’ve got a dipole that’s trimmed to be resonant at 14057.5 kHz. Project TouCans puts out a QRP maximum 5 Watts. Our field kit has evolved to that 5 Watts though. We started out with the Flying Rockmite at 250 mW, then we made a power bump to 750 mW, and then with the addition of a Tuna Topper amplifier and a lot of experimenting we finally achieved a QRP maximum 5 Watts output power.

The QRPp Rockmites–having so little power combined with lots of somewhat confusing reading about antenna matchers and coaxial cable and baluns–led to the original Flying Rockmite. “Do you know what makes you not have to discuss feed lines?” I reasoned, “Not having a feedline.” And so, the RockMite was inserted into the dipole. I brought the keyer controls down to me and sent the power up along an Ethernet cable. Continue reading Field Radio Kit Gallery: KD0FNR’s Rockmite 20 and Tuna Topper →

Antenna Tuners, Antennas, Homebrew, How To, News, Portable, QRP

BD4LB’s Simple Homemade L-Match for Field Operating

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Many thanks to HUAQIANG Gu (BD4LB) who shares the following information about his homemade L-Match. Note that BD4LB doesn’t speak English, and I don’t speak Chinese, so the following was machine-translated via Google Translate:

Homemade L-Match for Field Operating

by HUAQIANG Gu (BD4LB)

L-MATCH has a simple structure and is easy to make.
It is mainly composed of a coil and an adjustable capacitor.

  1. The coil is made of copper wire with a diameter of 1.8mm, and the outer diameter of the coil is 50mm.
  2. The capacitance of the thin film adjustable capacitor is 0pF–200pF.
  3. When using, a balanced ground wire needs to be installed.
    (Different bands, multiple quarter-wave length wires, and together. I use a row of wires. For example: two balanced ground wires 10 meters and 5 meters long, respectively 40 meters band and 20 meters band balanced ground wire.)

After many outdoor communications, I adjusted the end-fed antenna. The length of the radiator was 10 meters, which was appropriate.

One end of it is hung from the top of a 6-meter-long fiberglass fishing rod. On the other end, connect the red binding post of L-match.

Balance the ground wire and connect it to the black binding post. Spread it out on the ground.

The L-match is placed on the ground and connected to the HS1B or KVE60C antenna analyzer using a one meter long 50-3 coaxial cable. (This reduces the length and weight of the coaxial cable.)
When using an inverted V antenna, the length of the coaxial cable needs to be at least 8 meters.

My outdoor communication is mainly on the top of a hill in the park, or on the beach by the sea.

On the beach, there is plenty of space. In addition to setting up end-fed antennas, you can also set up inverted V antennas.

On the top of the mountain in the park, the space is limited, and it is difficult to deploy the 20-meter-long antenna oscillator. Only 10-meter end-fed antennas can be used.

After fixing the fishing rod, installing the antenna radiator and balanced ground wire, first connect the antenna analyzer KVE60C.
Use copper alligator clips to clip on the coil and adjust the adjustable capacitance to minimize the standing wave ratio of 7.023 MHz.
(Change different coil taps, adjust the adjustable capacitor, and try several times.)

I carry a compass to adjust the transmitting direction of the end-fed antenna. I won’t get lost.

The actual communication effect is quite good.

In the 40-meter band, it is suitable for short-distance communication within 800 kilometers.

In the 20-meter band, it is suitable for communication within 1000-2000 kilometers.

Antennas, Funny, Hams, Homebrew, News

QRPer Notes: HA8SA’s Homebrew Transceiver, BuddiHex Review, and “Marine Mobile” in Iowa?

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Because I receive so many tips from readers here on QRPer, I wanted way to share them in a concise newsletter format.  To that end, welcome to QRPer Notes, a collection of links to interesting stories and tips making waves in the world of radio!

HA8SA Stay At Home Transceiver

Many thanks to Pete (WB9FLW) who shares a link to HA8SA’s compact homebrew transceiver. As Pete notes, it’s a “very simple design but with a load of features!”

Click here to check out details on HA8SA’s website.

Buddihex review

Many thanks to John (VE3IPS) who writes:

I think the QRPers will be happy see the BuddiHex review:

https://ve3ips.wordpress.com/2022/11/10/buddipole-buddihex-deployment/

John VE3IPS

“Marine Mobile” in Iowa?

Many thanks to Rand (W7UDT) who shares this brilliant little video from K0KLB’s YouTube channel:

Had a lot of fun experimenting RMOOTA (Random Metal Objects On The Air) with the boat today.. The winds were so strong (sorry about the annoying wind/mic noise) and the noise of the engine kept us from actually driving while making QSO’s.. It was a challenge just the same being stationary in one location.

It was a big contest weekend and the QRM and Pileups were massive.. With my 5w and Random Metal Object as an antenna, it was difficult to get contacts.. I was able to catch them when they were short on business and looking for calls, lol..

We only achieved 4 QSO’s out of the 10 we wanted.. (40%) but, I’m happy with that.. I felt lucky to get one call, LOL..

Thanks for watching everyone.. We (the Skipper and Mate) hope you enjoyed watching it as much as we did making it. 73, Kevin ~ k0klb

The Lyrics written and sung by K0KLB

Many thanks to everyone for sharing their tips here on QRPer Notes!

Antennas, Guest Posts, Homebrew, How To, News, Portable, QRP

Sam builds a tiny tabletop HF antenna

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Many thanks to Sam Duwe (WN5C) who shares the following guest post:

A (surprisingly good) tabletop HF antenna

by Sam Duwe, WN5C

I recently built a tabletop QRP HF antenna for 17 and 20 meters, in the spirit of the Elecraft AX-1, so I could operate at lunchtime on the campus where I teach. My wants were something small, that would fit in my work bag, that didn’t require a tuner, and could work on a couple of different bands. But on a lark I decided to attempt a POTA activation at Lake Thunderbird State Park (K-2792) pairing this antenna with my Penntek TR-35 QRP CW transceiver. I figured I’d maybe get one or two QSOs and then switch to a long wire in a tree. But what happened amazed me.

I talked to seemingly everyone. Beginning at 9:00 AM September 26th I worked both 17 and 20 meters for an hour and a half and made 37 contacts from across the country. I even had a Swiss guy call me back on 17 but he faded before we could finish. This antenna, at least as a CW POTA activator, works. Granted conditions were very good, but I’ve replicated this multiple times in the past few weeks, just recently at a picnic table in the parking lot of the Route 66 Museum (K-8644) in Clinton, OK (there is quite a thrill in urban activations).

It has also reasonably low profile and very quick to setup and take down. It is also quite a conversation piece when I set it up at school. I elevated the counterpoise by attaching it to a nearby oak and an interested undergrad sheepishly asked if I was listening to the tree!

The build is pretty simple. Physically the antenna consists of a small painters pole from Walmart and an old tabletop camera tripod. I found a nut that fit the screw portion of the tripod and hot glued it into the orange connecting section of the pole. That way the tripod can then be screwed onto the pole. The RF parts of the antenna consist of a 38” telescoping whip that I scavenged from the rabbit ears antenna that came with my RTL-SDR. It connects using the original connector which was hot-glued into a hole I drilled into the top of the painters pole. I found similar small 3 or 4-foot whips from AliExpress for cheap and these would probably work fine.

I then soldered a long length of speaker wire that was wound into two coils: the top for 17 meters (24 turns) and the bottom for 20 meters (25 turns plus the former 24-turn coil). The speaker wire was the soldered to the center of a BNC connector which I hot glued and taped to the pole. I soldered a short piece of wire from the shield of the BNC for the counterpoise and added an automotive spade connector to attach to a 17-foot length of wire. I also included a switch between the coils and the BNC connector to select either just the top coil (17 meters) or both coils (20 meters) using solder, hot glue, and tape.  I then covered my shame in silicone tape.

The most time-consuming aspect of the project was tuning the antenna. It required trial and error to first tune the number of turns on the 17-meter coil and then the 20-meters coil. I extended the counterpoise (for me it’s best when slightly elevated) and the telescoping whip. I performed the tuning with the whip not fully extended to give room to tune in the field. Using a nanoVNA was useful here, as was soldering a pin to the wire to poke through the wire at various parts of the coil to find the best SWR.

In use, the antenna can be affected by both body capacitance and how the counterpoise is situated, so I found that an in-line SWR meter was helpful in making sure all was well. Once set up it is easy to fine tune by just adjusting the whip length. 1.5:1 SWR is about how well I can tune on average. Obviously if you have a tuner you would just have to get it close.

There are a million variation on a small base-loaded vertical antenna, and you can definitely improve upon this design. And, besides the super well-built and elegant AX-1, QRP Guys sells an interesting looking kit, and there are some good 3D printed designs I might want to try out. But regardless how you go about it, it might be worth giving a tiny antenna a shot.

72, Sam WN5C

Articles, Guest Posts, Homebrew, How To, Morse Code, News, Portable, QRP

Sam builds a compact external speaker and 200 Hz filter for the Penntek TR-35

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Many thanks to Sam (WN5C) for sharing the following guest post:

A Compact CW Filter and Speaker Build for the TR-35

by Sam Duwe, WN5C

I recently built a Penntek TR-35 and, like seemingly everyone, I love it.

Once the rig passed the smoke test I was having too much fun and wasn’t quite ready to put away the soldering station. I had two non-essential wants for this project: a narrower CW filter for listening comfort, and an external speaker. Here’s a quick description of how I crammed both of those into an Altoids tin. Nothing is new or groundbreaking here, but it has been a fun and useful project for me and hopefully will give some inspiration for others.

The Hi-Per-Mite

The heart of the project is a Hi-Per-Mite 200 Hz CW filter, designed by David Cripe NM0S, and sold as a nice kit for $28 by Four State QRP Group. Hans Summers G0UPL uses the circuit in the QCX so many will be familiar with the filter’s sound. It’s nice and narrow with no ringing, and makes using my base station (a Kenwood TS-520 with the 500 Hz crystal filter) a joy.

To be clear, the existing narrow filter in the TR-35 is great, but I like the option of going narrow(er). It’s a Pixie-level build difficulty so it should come together in an easy couple of hours. I originally built mine in an Altoids tin using inspiration from Phillip Cala-Lazar K9PL’s review and it worked very well. It sips current and is powered by a 9-volt battery. With a DPDT throw switch connected to both the audio path and the power you can easily switch the filter on and off.

The Speaker

A neat aspect of the TR-35 is that there is a lot of audio gain so you can drive a non-amplified speaker. I have a little Bluetooth speaker that does this trick when I want to use CW to annoy people, but I figured if I’m already hauling an Altoids tin to the field maybe I could get it to talk, too. I looked around my junk box and found a broken Baofeng speaker mic and salvaged the speaker. It works really well: a robust but comfortable volume.

I’m sure any little speaker would do the trick… nothing fancy here, it gets hot glued it to the lid of a mint tin after all.

The Build

After I built the Hi-Per-Mite here’s what I did: first I ate a tin of Altoids and felt a little sick. Then I drilled some holes. The one on the left is for the audio input, the one on the bottom for the headphones (both of these are 1/8” stereo jacks), and two on the right for two mini DPDT switches. I also drilled holes in the lid for the speaker sound to come through. I gave the tin a good sanding and tried to remove sharp edges, and then sprayed the lot with black primer and spray paint.

Continue reading Sam builds a compact external speaker and 200 Hz filter for the Penntek TR-35 →

Articles, Homebrew, How To, Morse Code, News

Scott Builds a clever Icom IC-705 Paddle Mount

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Many thanks to Scott (KK4Z) who shares the following project from his blog KK4Z.com:

Paddle Mount for the IC-705

I kinda like the idea of being able to mount your paddle to your radio when operating portable. You can use the weight of the radio to help prevent the paddles from moving around and it frees your off hand for other tasks. We see examples of this with the Elecraft KX series of radios and there are some adapters for radios such as the Yaesu Ft-817/818.

I really like my IC-705. It is probably my best radio for POTA/potable operation. I think the only time I would leave it home is if weight became a problem or I needed to exercise one of my other radios. Recently, Begali came out with a mount to attach their Adventure paddle to the IC-705. It is a sweet set-up; however, the approx. $400 USD price tag got me looking for other alternatives. I have nothing against Begali, I own three of their paddles, and they are superb instruments. I think I wanted to tinker, and this gave me a good excuse.

For paddles, I have a set of Larry’s (N0SA) SOTA paddles. I love these paddles. When I go on an activation/Portable Operation, I bring these and my Begali Travelers. If I was going to do a SOTA activation, I would just bring Larry’s Paddles. Next was a trip to Tractor Supply Company (TSC) for a sheet of 16 ga. Steel. That set me back $16. I cut it to 3″ by 3 1/2″ using a cutoff wheel on my grinder.

I already have a stand I made out of 1″ x 1″ angle aluminum so I cut this to fit behind it.

The blue on the metal is Dykem Blue which is a layout fluid. In creating this project, I am only using hand tools. Power tools consisted of a grinder with a cut-off wheel. a hand drill, and my trusty Dremel tool. Here is a picture of me giving the mount a rough finish with a file. Continue reading Scott Builds a clever Icom IC-705 Paddle Mount →

Hacks and Hints, Homebrew, How To, Kits, News

Xiegu X6100: Two effective ways of mitigating broadcast band interference and overloading

18 Comments

As I’ve previously mentioned, the Xiegu X6100–at least at time of posting (January 17, 2022)–has overloading issues. If you listened to the activation video I posted yesterday, you can hear a local AM broadcaster punching through the 40 meter band, especially noticeable before/after operating SSB.

Several subscribers asked if I tried using the attenuator and RF gain to mitigate the level of overloading.  Attenuators and RF gain can be an effective means of mitigating noise levels, but they essentially affect everything on the band–all signals somewhat equally.

A better approach is to use a BCI Filter.

BCI Filters

BCI filters reduce or notch out AM broadcast band signals so that they don’t overload your receiver.

BCI Filters are placed between the radio and the antenna. They can have a dramatically positive effect if you live near a broadcast station and/or if you have a radio that’s prone to overloading.

I see them as a more “surgical” approach to solving broadcast band interference.

BCI filters are simple, inexpensive, and effective. Here are two options shared by QRPer readers: Continue reading Xiegu X6100: Two effective ways of mitigating broadcast band interference and overloading →