Category Archives: Guest Posts

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

21 Comments

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, Guest Posts, Kits, Morse Code, News, QRP, QRP Radios

Jonathan reviews the EGV+ QRP CW transceiver kit

6 Comments

Many thanks to Jonathan (KN6LFB) who shares the following guest review:

A review of the EGV+ QRP Transceiver Kit

by Jonathan (KN6LFB)

Introduction

The EGV+ is a QRP CW-only transceiver that covers the 40-, 30-, and 20-meter HAM bands.  Designed by Javier Solans, EA3GCY, it is sold in kit form from his website, qrphamradiokits.com.

Javier designed the EGV+ in honor of his friend and co-founder of the EA-QRP Club, Miguel Montilla, EA3EGV.  The first page of the instruction manual dedicates the radio to Miguel with this tribute:

This EGV+ transceiver is probably the kit that I have produced with more care and illusion in my life.  It is a great honor to name this kit “EGV”, the callsign suffix of the late Miguel Montilla, EA3EGV (SK). With no doubt, this is the kind of kit he liked most.  It was my privilege to establish and share with him the first years of the EA-QRP Club. He has always been a referent in my life; when I remember those wonderful years his humbleness, work capacity and generosity are the virtues which shine his image.

How lucky I was to be able to share the path with you, Miguel. Thanks! 

Javier Solans, ea3gcy 

Specifications

  • Frequency Coverage: 40m, 30m, 20m
  • Modes: CW
  • Power Requirements: 12–14VDC, 1–2A transmit, 0.14–0.25A receive. 

Transmitter:

  • RF Output: 5W @ 13.8V
  • Harmonics Output: -45dBc or better below fundamental
  • Other Spurious Signals: -50dBc or better
  • T/R Switching: Relays

Receiver:

  • Type: Superheterodyne.  Balanced mixers.
  • Sensitivity: 0.2uV minimum discernable signal.
  • Selectivity: 3-pole crystal ladder filter, 700Hz nominal bandwidth
  • IF: 4.915MHz
  • AGC: acts on the receive path according to the received audio.
  • Audio Output: 250mW, 4-8 ohms.

Ordering

I purchased my EGV+ kit with the optional enclosure from qrphamradiokits.com.  Javier requests that US customers email him using the contact form on his website for the current pricing in USD prior to ordering.  At the time of my order (February 2022), the cost with the optional enclosure was $203.37.

Assembly

The EGV+ is a single large (180x140mm) PCB, with separate modules for the OLED display, processor, and Si-5351 frequency generator.  All components are through-hole and placed on the top of the PCB.  The kit arrived well packaged and well organized.  There were no missing or mislabeled parts in my kit, which is impressive considering the high number of components.  There are 53 100nF capacitors alone!

The manual contains detailed lists of the components by value/quantity and individually.  One of my favorite features of the manual, and something I wish was more common, is a grid-based layout map of the entire PCB [see above], with the grid position called out in the list of individual components.  This greatly speeds assembly and diagnosis as you can find component positions more easily.

Continue reading Jonathan reviews the EGV+ QRP CW transceiver kit →

Articles, Field Reports, Guest Posts, Morse Code, News, POTA, QRP

Brian’s Kilo at Cook Forest State Park is tied to family, memories, and his CW journey

13 Comments

Many thanks to Brian (K3ES) who shares the following field report:

Field Report:  Reflections on a Kilo at Cook Forest State Park

by Brian (K3ES)

Contemplating my favorite antenna tower during the Kilo activation.

Cook Forest State Park in northwest Pennsylvania has always been a special place for me.  It abounds in trees (including some of the last virgin timber around), wildlife (deer, turkeys, song birds, squirrels, and the occasional bear), and also includes the scenic Clarion River.  When I found out about Parks on the Air (POTA) after getting licensed in 2020, I knew that I had to put POTA entity K-1345 on the air.

Our family cabin; which has been central to all of the phases of my life – including milestones, joys, sorrows, and unadulterated wonder – is located on a plot of land bordered on two sides by the park.  It just seemed natural and right for me to do my first-ever POTA activation under an ancient hemlock tree just a few steps over the line from the back corner of our property. That mostly-SSB activation happened in May 2021 with my TX-500 pushing 10 watts into a homebrew dipole suspended from a dead branch up 30 ft in the hemlock.

An early activation of K-1345 from beneath the ancient Eastern Hemlock Tree

Last weekend, I reached a meaningful personal goal by completing my 1000th activator contact from K-1345.  After the first activation I never again operated mostly-SSB, and I never increased radiated power.  Nearly all of my contacts since have used CW, and many were completed at 5 watts.  The added challenge of QRP CW undoubtedly made the Kilo more difficult, but it was also much more fulfilling.  It has taken me 28 successful activations, a lot of work to improve my CW skills, and a lot of patient support from the hunters who have shared this journey with me.

My activations at K-1345 tell the story of my journey as a CW operator.  I took my first steps on that journey in late 2020, months before I had a portable radio or a plan for my first activation.  I started with an Android app, V-Band, and listening to CW exchanges on webSDR.  Eventually that progressed to CW Academy basic, intermediate, and advanced classes.  The classes really upped my CW game, but what helped even more was using CW on the air.  I finally got my HF station on the air in March 2021 and started hunting parks, SSB at first, then increasingly CW.  During my first mostly-SSB activation I did manage to hunt down three park-to-park contacts using CW.  I started my second activation by calling CQ using CW, and I have not looked back.  Wow, those hunters were patient during that first first CW activation!  My skills have improved greatly since then, but I’m still not where I want to be.  The next goal for me is to gain confidence and proficiency in less-structured QSOs.

I want to thank Thomas – K4SWL, whose real time, real life activation videos challenged, motivated, and inspired me to learn and use CW.  I greatly appreciate the work of the CW Academy advisors who guided me through some of the hard work needed for improvement.  I also need to thank the hundreds of hunters who have patiently endured my developing CW skill set. Finally, my hat is off for the dedicated POTA volunteers, who continue to improve and expand this amazing activity to the benefit of radio amateurs around the world.

Completing the Kilo activation would have taken me longer if it were not for the tremendous encouragement provided by my gracious, intelligent, and beautiful XYL.  As I was contemplating indoor chores on a Friday morning, she pointed out the opportunity to go out and activate during the best weather of the weekend, and save the chores for a rainy day.  Who am I to argue with such impeccable logic?  Off to the woods we went!!!

I made a point of using the TX-500 with the homebrew dipole suspended in that ancient hemlock tree to complete the Kilo activation, going back toward the starting point, as it were.  Of course I did finish with CW mode and 5 watts to commemorate my personal growth during the journey, too.  I was set up to go by mid-afternoon.  Needing 57 contacts to complete the Kilo, I decided to get some contacts on 20m, then move to 40m a bit later.

Getting started on 20m.

After calling CQ for almost half an hour to get two contacts, I decided to move to 40m a bit sooner than planned…

With the antenna lowered, I am reconnecting the links for 40m.

40m was hot!  I completed the eight additional contacts needed for a successful activation in less than 15 minutes.  By the 2 hour mark, I had racked up a total of 69 contacts and finished the Kilo.

As a final note, I picked up 55 more contacts on Saturday, bringing my total CW mode contacts over 1000.  The rain started early Sunday morning, and I got my indoor chores finished after all.

Gear for the Final Activation:

Photos

An arborist throw line works great for setting up the antenna here!
Almost any weather is great when you are doing a POTA activation!
But sometimes cold fingers limit your endurance…
My starting kit for the TX-500.
Antennas and accessories for the TX-500 kit.  Home-brew linked dipole is on the right.
Arborist throw line for the TX-500 kit.
TX-500 kit packed for POTA!
Guest Posts, News, QRP, QRP Radios, Vintage

Joshua acquires an Argonaut 509

13 Comments

Many thanks to Joshua (KO4AWH) who shares the following guest post:

Ten-Tec Argonaut 509 Acquisition

by Joshua (KO4AWH)

My club president sent me a text on Sunday before our Monday club meeting. He wanted to know if I was interested in a Vintage 80s QRP Radio. He knows I have an affinity for QRP. Honestly, I think he is still amazed at how I managed to get through piles ups on his hexbeam during summer field day with my TX-500. Boy was that fun.

The deal was a Ten-Tec 509 with the microphone and CW filter, the matching 251 power supply with meter, and the 504 matching 50W amplifier. He sent me a photo, I had to look it up. I have heard of Ten-Tec, thanks to Thomas K4SWL, but certainly was not familiar with their Argonaut 509. I was intrigued. I don’t have a single vintage piece of equipment. I have only been a Ham for less than 3 years.

We had some equipment from a club member SK donated for auction to raise funds for some club repeater upgrades. This was a good excuse to purchase an old piece of equipment that I likely would not have purchased otherwise. After looking over the 509 and accessories, all of which were in great condition, I brought them home. Of course I couldn’t help but hook everything up and turn on power. Everything powered up but no movement of the frequency indicator, not a great sign, and no audible hint of changing reception frequency. After further inspection it seemed the dial tuning mechanism was seized up. Looks like another project.

The next morning, as I had a few minutes to spare I started taking things apart. I have never pulled apart an old transmitter before so I took my time as I studied all the components and marveled at the simplistic yet complex circuitry found under the covers. Once I was down to the tuning mechanism, a few desoldered wires later, it was removed and ready for cleaning. I don’t know if the grease was original, but it sure was hard. After carefully cleaning, greasing, and reassembling all the components, soldering a couple wires back, and reassembling the housing, I was ready to power it back up. I don’t want to understate the work involved, it can be quite tricky, but I really enjoy this type of thing.

After tuning around a bit and working with the controls on the Radio, I found a POTA operator to zero beat. I needed something to reference in order to adjust my knob indicator so I would know what frequency the radio is on. I actually received the manual for the radio and each of the components. Reading through a few key points the night before really helped out when I was ready to start tuning in and transmitting.

I had the amplifier on, I set the DRIVE to about half way guessing that was okay and called back to the Activator. First call, he called me back with a 59! WOW, I was excited. I let him know I was on an old Ten-Tec that I had just repaired and he came back and said the audio and signal were great. How exciting! So, naturally, I hunted a few more stations and then listened to a few rag chews as I got familiar with the Radio.

Not only was I excited to have repaired my first radio, I am also amazed at the capability of this Radio originally released in 1973. I am not a long time SWL or radio operator but there is certainly something very appealing to me about the audio this Rig produces. I wasn’t certain what I was getting into with this rig, but I sure am happy how it worked out! I may just be on the hunt for another Ten-Tec. I even plan to take this to my local park and do at least one activation with it.

Here is a quick excerpt from the introduction in the operating manual.

“The Argonaut opens a whole new world of excitement and fun in Amateur Radio. We think you will find QRP a welcome change. Five watts are only 2-1/2 S-units below 150 watts for the same conditions. When skip is favorable and QRM light, you will not be conscious of using low power.”

73

Joshua

KO4AWH

Antennas, Articles, Guest Posts, How To, News

Steve’s Homebrew Vertical Antenna for POTA

15 Comments

Many thanks to Steve (KM4FLF/VA3FLF) for sharing the following guest post:

A Great Homebrew Vertical Antenna

by Steve (KM4FLF/VA3FLF)

Last spring, I was going through my many boxes of ham “stuff” looking for items to sell at our club tail gate sale. I came across a couple of Hustler SM Series Resonators (20 /40 Meters) that I had acquired. I am not sure where I obtained them, but I decided they were keepers.  That decision turned out to be the first step in a year long process that has given me an awesome homebrew vertical antenna.

After doing a little research I found the resonators and accessories at most of the online ham dealers. They are used primarily as mobile and marine antennas. I had seen where a ham had used these on a ground stake as a portable antenna as well. I ordered a Hustler MO1 mast which is 54 inches tall and thought I would attempt to make a portable POTA antenna.

Antenna base

I had a couple of small aluminum plates that I drilled out a few holes. I cut out a notch to put a SO-239 Stud Mount on the plate as my antenna base. I now had a ground plate, connector, and antenna with resonator. By putting a stake in the bottom of the plate, I was able to get the antenna to stand up. The Hustler resonators have a hex screw for tuning that can be loosened. The antenna can be adjusted for resonance by lengthening or shortening the radiator length. After adjusting the radiator my SWR was still horrible on the two bands.

Antenna base close-up

I had some 14-gauge wire laying around and attached it to the plate using carriage bolts and nuts for my ground radials. I didn’t think about the length of the wires at this point but went with three or four lines around 20 to 30 ft. I was able to use my vertical a few times with moderate success. My SWR on 20 and 40 Meters was around 2:0 to 1 at best. It was bulky and very delicate. Sometimes screwing in or unscrewing the MO1 the SO239 would slide off the edge of the aluminum plate. I put away my contraption for the winter and decided to move on to something else.

In April of this year, I wanted to revisit my project. Continue reading Steve’s Homebrew Vertical Antenna for POTA →

Articles, Guest Posts, News

Paul’s potentially explosive portable ops in St. Elmo, Colorado

3 Comments

Many thanks to Paul (W0RW) who shares the following guest post:

Operating in St. Elmo Ghost Town, Colorado

by Paul (W0RW)

I have operated in St Elmo (Ghost Town) several times with my PRC319 Pedestrian Mobile.  St. Elmo is at 11,000 feet in a deep canyon so it was hard to make contacts.

My PRC319 runs 50 Watts and I use a 10 foot whip so I had some success to the East on CW. I use a Whiterook MK-33 for a hand held single lever paddle.

OLYMPUS DIGITAL CAMERA

Right after my last visit,  July 2015, members of St. Elmo and Chalk Creek Canyon Historical group  cleaned out the outhouse behind the Home Comfort Hotel in St. Elmo, they found a potentially explosive surprise. On the floor of the outhouse, they found what they believed to be dynamite. Later in the day the bomb squad found blasting caps rather than dynamite.

St Elmo Outhouse

[Per the Historical Society] there were only 6 Blasting Caps found at St Elmo’s. They called Ft. Carson US Army EOD and they blew them up right there in the center of town.

While the electric blasting caps are usually shorted and would not be effected by a QRP radio, my 50W radio was  at a dangerously high level to be transmitting near a box of blasting caps.

It would be a smart idea to avoid operating in any old mining areas where unexploded dynamite might exist.

Paul    W0RW

St Elmo, Colorado

Guest Posts, News

Importance of Electrostatic Discharge (ESD) Protection

5 Comments

Many thanks to Paul (W0RW) who shares the following guest post:

Sherlock Investigates: Electrostatic Discharge (ESD) Protection; Is It Still Needed?

Improper handling of electronic assemblies with microcircuits during testing, production, and repair can still cause catastrophic and latent damage. Designers have developed protection methods that reduce ESD susceptibility after the product is completely packaged, so you might not see any damage to final products, but those who build or repair electronic assemblies still have to take precautions not to damage items.

If you are familiar with and employ standard ESD handling procedures you will be safe. The ESD Association has training on their web site https://www.esda.org/esd-overview/

This is the most important ESD fact:

“Static is generated by the contact and separation of unlike materials”.

That means ‘you’ probably are the biggest ESD hazard around your workbench. When you get up out of your chair many thousands of volts can be generated. Grounded wrist straps prevent damage from this.

Humidity is a big factor in reducing ESD damage. If you live near the ocean you won’t have as much ESD susceptibility as someone working in Colorado.

It’s not only electronics that are affected by ESD. Perhaps you have seen the ESD warning signs on gas station pumps. People sliding out of a car that is being fueled has caused fires. Filling metal gas cans in pickup trucks with bed liners can be hazardous; The only safe way to fill a gas can is to place it on the ground.

The pictures shown here are from Sherlock’s Failure Analysis Laboratory. They show the physical damage to microcircuits that was caused by static electricity.

Sherlock (a.k.a. W0RW)  is a NARTE* ‘Electrostatic Discharge Control, Certified Engineer’ (ESD-00020-NE).

*National Association of Radio and Telecommunications
Engineers, Inc.

Articles, Guest Posts, QRO, QRP

Scott runs some QRO v QRP numbers!

8 Comments

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

QRO SCHMURO

There is always a lot of talk about QRP vs QRO, 5 watts vs 10, ad nauseam. So today I thought I would run the numbers and see what the real deal is. First we need a few definitions. An S-unit in general terms is the minimum change in signal strength to be just noticeable (k3wwp.com). In more technical terms it equates to approximately 6 db in change. The decibel (dB) is a logarithmic number. Each 10 dB represents a factor of 10 difference. This may be a little out there for some so we will cut right to the shortcut. There are two types of logarithms. For calculating dB, use the common logarithm which is base 10. To see if your calculator uses the right one. Punch in 100 and then log. The answer should be 2 which equates to 10 to the second power which equals 100. This is not a technical paper but an entry way to see how changing the power levels affect the signal level of your transmitting signal. As you guessed, it is not linear.

Let me introduce an equation:

Where Power P1 is the power you wish to evaluate and reference power P2 is your starting power. Let’s take going from 5 watts to 10 watts. The equation would look like this:

We take 10 and divide it by 5 which give us 2. Then we hit the log function on our calculator which gives us 0.301. Multiply that by 10 and you have about 3 dB in gain or about one half of an S-unit (remember 1 S-unit is equal to 6 dB). Let’s do one more by hand and tackle the QRP/QRO debate. How many S-units will increasing power from 5 watts to 100 watts give you? The equation looks like this:

Take the 100 and divide by 5 to give you 20 and then hit the log function to give you 1.301. Multiply by 10 for 13.01 dB. Divide 13.01 by 6 dB and you have 2.17 S-units. Going back to our definition that one S-unit is the minimum change in signal strength to be just noticeable shows that going from 5 watts to 100 watts is not that great of a change.

Let’s let the other shoe drop. What about going from 5 watts to 1500 watt? That will give you 4.13 S-units of gain vs 1.96 S-units going from 100 watts to 1500 watts?

This gives you a fairly easy equation to help you evaluate your needs based upon empirical data. Running 20 watts over 5 gives you 1 S-Unit. Using less power means less drain on the battery for longer operation. This is only part of the equation. Propagation, antenna, mode used, and station efficiency all play a part. Have fun and maybe don’t toss the QRP radio yet. 🙂

Click here to read this post and more at KK4Z.com.

Guest Posts, News, SOTA

Paul’s SOTA excursions captured on live webcams

2 Comments

Many thanks to Paul (W0RW) who shares the following guest post:

Can you See Me Now? Portable Operation From a Web Cam.

by Paul (W0RW)

There are now thousands of web cams operating around the world and they make great portable operating locations.

By watching a webcam stream, the stations who works you can watch you live as you talk to and log them.

When I am activating a site with a live webcam, I post the web cam link on my QRZ.com page and then stations who contact me can then go to QRZ, click and watch. I usually have a big sign that shows up on the web cam with my call and my frequency. Even DX guys who can’t hear me can watch me operate.

Many web cams are now live streaming; they give you fast refresh rates and real time video. Other bandwidth limited cams refresh at slower rates and may give only 1 frame every minute.

I was at the ‘Teller 1 Web Cam’ on 8 June 2022 (see photos above) and made 10 Q’s on CW and 10’Q’s on SSB. It has an almost real time video but with a delay of about 10 seconds. It is at 10,000 feet.

The HD Pikes Peak Panoramic Cam that I frequently use (At 14,115 feet) has a revolving 1 minute refresh rate.

I am standing right above the ‘RW’ sign.

The remote Independence Pass, Colorado, Web Camera is a solar powered wireless camera with a 1 minute refresh rate. I am standing just to the left of the tree.

This camera is down now and won’t be back on line until July.

Paul w0rw
Colorado

That makes for a fun dimension in playing SOTA, Paul! Thank you for sharing. So far, I haven’t activated a summit with a webcam, but it looks like there are numerous ones in Colorado. I’ll have to keep this in mind before heading out there!

Field Radio Kits, Guest Posts, Hacks and Hints, Hams, News, Portable, QRP

VO1DR’s Cheap and Bomb-Proof Field Package for the Icom IC-705

15 Comments

Many thanks to Scott (VO1DR) who shares the following guest post:

Cheap and Bomb-Proof Field Package for the IC-705

By Scott Schillereff (VO1DR)

St. John’s, NL, Canada     

Since getting my novice ticket in 1970 (WB9CXN) under the watchful direction of Charles “Rock”  Rockey, W9SCH (SK), I have been a dyed-in-the-cloth homebrewer and QRPer.  My one and only commercial rig before this year was a Ten Tec PM-3 I bought with paper-route money in 1971 (still have it).  Fast-forward to today.  I now live in Newfoundland, and Europe is as close as Georgia.  I continue to build my station components and antennas.  A recent sea-change though – I inherited some money and decided to splash out on a for-life rig that would serve well in the shack and on the road (RV or hiking).  After researching options, I settled on the ICOM IC-705.  A fantastic performer; a receiver like I’ve never heard before; more bells and whistles than I could dream of, and a form-factor like a….. delicate, expensive brick!

The 705 is not a sleek, trail-friendly radio.  It’s on the heavy side and, well…awkward to pick up!  But, man, what a radio!  So, my first step was to buy a Windcamp ARK-705 exoskeleton.  This protects the rig on all sides and gives you something to grab onto.  I don’t mind the weight and size; I want this rig to be working in 25 years.

My operating interests are home use, mobile in my 25 ft motor home, and portable on day hikes.  I’m new to POTA and SOTA but maybe that’s next, thanks to you, Thomas!

I’m genetically wired not to buy the luxury ICOM backpack; I prefer to build my own and integrate with my hiking gear.  With that in mind, I would like to share my field package system to move the 705 around safely with little risk of damage.  Also some other homebrew portable gear. Continue reading VO1DR’s Cheap and Bomb-Proof Field Package for the Icom IC-705 →