N2EC Amateur Radio

Ed's Adventures in Amateur Radio

Tag: Review

  • Building the Penntek TR-35

    Building the Penntek TR-35

    A while ago I saw a review of the Penntek TR-35 and I thought to myself that this could be one of the best options for a super-portable POTA CW transceiver. It is incredibly small, has very low power consumption, has great audio, pleasantly narrow CW filtering, has four bands that are heavily used in POTA (40m, 30m, 20m, and 17m), and is a kit to boot. I ordered one with the optical encoder option (now standard) and then life got in the way and it sat on my shelf for longer than I’d like to admit. Then one weekend I had plans fall through that suddenly gave me unexpected free time, so with a desire to spend some time behind my magnifying glass and soldering iron, I pulled down the TR-35 from my shelf and got to building.

    The first thing I noticed was that the kit was organized better than any kit I had ever done. Each step on the manuals had a sealed bag connected on a strip that kept them all together. This eliminated one of the more tedious first steps for building a kit: part inventory. It meant that instead of having a big pile of parts, you only had to deal with what you needed for that step. Absolutely fantastic. The kit consisted of an upper board with the user interface elements (display, knobs, LEDs, and switches), a lower board with the RF components, and a specially made case. Construction started with the upper board and installing the 16 MHz crystal which needed to be installed with a gap from the board. Next came a pin header and the OLED display which was cleverly suspended from the board with standoffs and connected via leads from sacrificial resistors. Then LEDs, capacitors, jacks, switches, potentiometers, and the tuning encoder were added. The assembly was straightforward, although the encoder did require some fairly fine solder work with only a few millimeters between the pins. Finally the switches and knobs were soldered using the front of the case as a jig to ensure alignment. It sounds complicated, but it was fairly straightforward in practice.

    The TR-35 Upper Board Assembly

    Next came the lower board assembly, starting with the relays and a polyfuse. Then some jacks and potentiometers were added along with some FETs and a series of capacitors. Then it was time for the final amplifier, an IRF510 FET complete with a heat sink, mica insulator, and a plastic spacer to provide electrical isolation between the FET’s metal tab and the mounting hardware. This proved to be a tricky step as the initial placement of the FET requires it to be bent over. When I first did this there was enough tension from the bent over leads that even with the plastic spacer the FET was shorting out to ground. I had to disassemble things a bit and bend the leads so that it was no longer pressing against the mounting screw. After a few attempts the continuity function on my multimeter was no longer beeping at me and we had success. The next step was the installation of the many toroids required for the radio. There are many people who do not like winding toroids. I don’t mind winding them and find the process somewhat meditative, but I understand how they could be frustrating. For the toroid averse, this kit provides the answer: all the toroids needed are pre-wound at the factory and the enamel pre-stripped as well. If you can install a capacitor on a board, you can install the toroids here. Simple as can be. The toroids were then followed by a bank of 4 filters that needed to have their cases grounded as well. Then we were near the finish line and needed to do a bit of assembly to get the pin headers lined up so that the lower assembly would be electrically connected to the upper assembly. After a lot of solder connections were made, the two boards were mated and the microcontroller was installed and we had an assembled radio.

    TR-35 Lower Board Assembly

    Now it was time to check my work. There were resistance checks for the 3 power supply rails to ensure there were no shorts, and then I hooked it up to an antenna, power supply, and an external speaker and powered it up for the first time. Right away the display came to life and showed 7030 kHz. I could hear sound too and no “magic smoke” had been released – a welcome result. I went through several tests of functionality ensuring switches did their thing, knobs changed the desired functionality, and then made my way to the encoder. While it could be clicked to change the tuning steps, it wasn’t changing the frequency on rotation. Something was wrong. Remembering the tiny pins that needed to be soldered earlier and the fact that it had partial functionality, I powered everything down and disassembled the boards to inspect the pins. I saw some pins that may have been a bit light on solder. I had been conservative on the solder to avoid bridging the fine pins. I gave each pin a bit more solder, gave a continuity test to each pin to make sure I hadn’t bridged them, and then re-assembled the board. After getting everything connected the encoder changed the frequency as it should have done from the start. Success.

    Next it was time to bias the final RF amplifier, a process that involved using a digital multimeter in current measuring mode to measure the receive current drain (in my case a very small 79 ma) and then to transmit at the very lowest power output which caused the current draw to go up about 11 ma. From there you adjusted to have the draw go up another 5ma and the PA was successfully biased. Further adjustments were made to set the CW sidetone level to a pleasant volume with a potentiometer. One thing that is unique about this kit is the sidetone you hear is actually your transmitted signal, giving you silky smooth QSK. If you’re using an unprotected lithium battery, you can even set the voltage for a low power warning. I will be using a regulated supply or a battery with a BMS, so I skipped that step. Finally, you adjust the CW narrow bandpass filter to be properly centered by listening for peak amplitude and then you’re done. All that was left to do was assemble the case, install the knobs, LED lenses, vinyl switch covers, and the rotary encoder.

    After getting it all together I started spinning the dial around the bands and I was amazed with how low the noise floor seemed to be. The CW signals seemed to pop-out from the background noise and sounded quite pleasant. There are two CW filter modes, one very wide filter around 1.6 kHz and a narrower filter at 350 Hz, albeit with somewhat soft skirts. At the narrower filter setting noise and adjacent signals drop dramatically. I started calling CQ and looked onto the reverse beacon network and saw I was being received well into Europe on the East and West nearly across the US on 40m. Sadly, there were no takers to my CQ, and I decided to give the 30m band a try.

    Reverse Beacon Spots on 40m

    On 30m I had similar RBN results, getting into Europe and across the United States. I heard a signal about 1 kHz down just faintly as I was calling CQ so I paused for a moment to see who it was. It turned out to be Wolf, DF2PY in Germany calling CQ. I had the pleasure of working him in the past, so I decided to return his call. He heard me gave me a 549 and I heard him a solid 559 and we had a nice chat about home built rigs (he also likes to build rigs) until we were taken out by some QSB. Not bad for a first contact on the rig. In the next day I was able to contact Curacao on 17m as well with 1 Watt. I also made contacts with Oklahoma, Mississippi, Missouri, Pennsylvania, Michigan, Florida, New York, New Jersey, and Central Virginia on the 40, 30, 20, and 17m bands. The rig is a lot of fun, and most of the stations I called I was able to work. I even broke a few POTA CW pileups by going off frequency and using the RIT control to listen to the activator on their frequency, thus making my signal stand out from the zero beat crowd. I am very pleased with the results.

    So now that we know it works, what can it do? Well, the power output is variable and somewhat based on input voltage. On the lower bands I can get as much as 9 W out with the output power getting lower as the frequency goes higher. There is an RF output knob that allows you to change your power output, if desired. One thing you notice about the TR-35 is there are no deep menus to learn, almost every function has a button or knob dedicated to it. There are knobs for keyer speed, RF power, RF gain, and volume as well as an optical encoder for the VFO that is smooth and stepless. Pushing in on the VFO encoder changes your step, allowing you to go by 10 Hz and 100 Hz increments with a short press or by 1 kHz increments with a long press. When it comes to switches, you have a power switch, as well as a couple momentary switches that are bi-directional. The first momentary switch allows you to change the receiver mode from wide to narrow bandwidth if pressed up quickly, or to a full SSB width if long pressed. If pressed down it allows you to access the CW memories (there are 2) that are selectable by hitting either the dit or dah side of your paddle. A long press down allows you to program those memories. The final switch allows you to switch bands with a single fast press cycling 40, 30, 20, and 17 and then back again. If you long press up on this switch it will store the current frequency into a band memory. To recall that memory you would press up quickly twice. Finally pressing the switch down engages RIT allowing you to modify your receive frequency while maintaining your transmit frequency. Very helpful for those callers who may be calling you off frequency and not in the center of your filters. This can also be used to allow for split operation, albeit in reverse. Long pressing down will engage a dial lock, useful if you’re running a frequency and don’t want to accidently go off frequency. There are also LED indicators for signal reception (which shows as blue), red for a low battery warning that is configurable to your preferred voltage via an internal potentiometer, and RIT activation via an amber LED. Another useful feature is that this radio has 2 key input jacks: one for a paddle and another for a straight key. You can have both hooked up simultaneously, in fact in my shack I keep both connected to make for easier tuning with the straight key, or to switch things up if I feel like going manual.

    So everything sounds pretty good, right? Well there a few things to note that are missing. There is no internal way of knowing what your output power is, and the output varies by band and input voltage. If you have a wattmeter you could make a table of dial positions and output powers, but you won’t see it on the screen. Also, the TR-35 does not have an SWR meter, so you’ll want to pack one, or have an antenna tuner available if you plan on using a non-resonant antenna. I have these in my arsenal, so I can deal, but it would be much nicer if the SWR were displayed either on the OLED screen or via some LED metering. Finally, I do get a significant reduction of output on the 17m band, and I’ve reached out to Penntek to see if they have any idea why this is. I have made plenty of contacts on 17m with the 1-1.5 W I’ve measured from the radio, but when 40m and 30m are 7-9 W and 20m is about 3.5 W, 1-1.5W is a big drop-off.

    All in all, I have been very pleased with my new TR-35. At time of this review they are currently going for $319 as a kit or $419 fully assembled from the Penntek web site. While not the cheapest radio out there, I have been impressed with the quality of the kit and the wonderful sound that it is capable of producing. I look forward to getting it out in the field for years to come.

  • HamGadgets Ultra PicoKeyer Kit Build and Review

    HamGadgets Ultra PicoKeyer Kit Build and Review

    One of my goals for this year was to become a more capable CW operator and be able to have a valid POTA activation using nothing but Morse code. While I haven’t activated solely with Morse code as of this writing, I did get 11 contacts during my activation at Theodore Roosevelt Island on 5/28/2022, which would be a valid activation if taken by itself. I was able to hit this milestone well before I thought I would be able to, which surprised me. What surprised me even more is how much I enjoy working CW. While I have a straight key, I’ve found that I enjoy using an iambic key for operating as it does a great job at keeping the code I’m sending consistent and on-speed. For portable operation, my Icom IC-705 has a built-in keyer that does a great job, but for my older Kenwood TS-440S that I use at home, I need to use an electronic keyer in tandem with the key to get my code on-the-air.

    To that end, I had been using the Morserino kit that I reviewed earlier. It does a great job as a keyer (as well as being great for code practice and echo training, along with many other features), but it has one feature that makes it difficult to use as a dedicated keyer. After a period of inactivity it shuts itself off to preserve battery life, even if it is plugged-in. After having it shut-off in the middle of a couple MVARC CW Roundtables right before my turn to send, I decided I needed a dedicated electronic keyer. Thankfully, Thomas (K4SWL) had a write-up of an activation at QRPer.com where he was using a Yaesu FT-817ND without a built-in keyer and was using the HamGadgets Ultra PicoKeyer. It looked like a great solution, so I went on over to eBay to order one for $44.95 plus tax and $5.95 in shipping. Since my purchase the price appears to have gone up about $5.

    I ordered on June 9 and it was at my door June 13 via the US Postal Service. It was well packed inside a cardboard box filled with two poly bags containing the parts and a case. Some newspaper served as padding inside the box and everything arrived as expected. I went to the HamGadgets site to download the instruction manual, did a quick inventory of the parts, turned on my soldering iron, and got down to business.

    The build itself was very straightforward and consists entirely of through-hole components. I was able to finish the entire build in about an hour of relaxed assembly. The instructions were clear and easy to follow. The only hiccup was that the instructions mentioned a few capacitors that were supposed to be on a paper holder that were loose within the poly bag. There are a couple different types of capacitors in the kit, so I needed to inspect the labels on them to ensure I was installing the right ones. Thankfully, the needed information was on the instructions, and after a little squinting, I was able to identify which ones went in what places. In all there is a coin cell battery holder, 3 x 3.5mm (1/8th inch) stereo jacks, 4 momentary push-button switches, a potentiometer, 2 transistors, 3 capacitors, a small speaker, and a microcontroller chip with a DIP socket to install. There are multiple capacitors provided so you can tailor the sound level of the headphone output, depending on the impedance of the headphones you would like to use. When you’re done with the circuit board build the moment of truth comes when you insert the CR-2032 coin cell battery (provided). If everything is wired up properly, the on-board speaker sends “73” on power-on. Happily, I was greeted with a cheerful “73” and everything worked the first time.

    With the circuit assembled, it was time to put it into its case. When you buy the kit from eBay, they mention that there are 6 colors available for the front and back panels (black, white, blue, gray, green, and red). There isn’t a check-box, so make sure you put in as a message to the seller on check-out or you’ll get the default color of black. I requested the red panels and they fit the case snugly. They look to be 3D printed with recessed labels for the buttons and jacks. The case itself appears to be injection molded plastic and is held together with a couple screws that are provided. Once it is together it makes for a handsome little box that is quite small (a photo below shows a quarter for scale alongside my CWMorse Pocket Paddle).

    Once it is all together, the unit is ready to be connected to your paddles via a 3.5 mm stereo cable (not provided). 3.5mm jacks are also provided for a pair of headphones (without volume control — that’s why the capacitor selection is important) and to control the key input on your rig. By itself, it works as a practice oscillator, and teamed with your radio you’re ready to transmit. Out of the box the key speed is set to 13 words per minute if the potentiometer is fully counter counter-clockwise. Otherwise, the potentiometer allows you to change your speed between two values that you can set — by default the range is 5-30 WPM, but 5-60 WPM is supported. The full left rotation setting is also able to be set, so you can set a favorite speed for the far left rotation, then QRS or QRQ as needed. Although the potentiometer is analog, the actual setting is digital. If you would like to know what speed you are sending pressing the buttons for ▼ and ► together (the second and fourth buttons) will send the current speed in Morse code over the internal speaker.

    Pressed by themselves, the four buttons act as memory keyers. They are easily set by pressing the button until a “K” is sent through the speaker. Then key the message desired into memory, press and hold the same button, and when you hear an “R” you’re done. To abort, press any other key instead. Short pressing the key will now send your message at the current speed. This is very helpful for sending a CQ message repeatedly, as well as for sending your call, or a contest exchange. There is even an option to use a QSO counter for contests that have a serial number in the exchange that gets incremented during each QSO. The memories even have their own scripting language of sorts to allow for words to be repeated, pauses to be inserted, QSO numbers to be incremented, speed to be changed, and for things like QRSS to be done. The repeats can be especially helpful as the memories themselves are limited in length, so using the scripting commands (using the / character) allows you to get more out of the memories. Each of the 8 main memories can contain 127 characters. They can also be chained together using the commands. There are 4 messages readily accessible, and in the settings menu you can move to a second bank if desired, but this is not something you’d be able to do quickly during a QSO.

    There is also an extensive setup menu (entered using the ▲ and ► key combination — buttons 3 and 4) that uses Morse code to communicate with you to announce the feature, its current value, and then allow you to modify it using the buttons. I found most of the defaults to be satisfactory, but you can modify the stored speed for the fixed speed, the QSO number, set the range for speeds on the potentiometer, enable or disable automatic letter spacing, enable or disable leading zeroes for the QSO numbers, set a beacon delay, change the weight for the code being sent, enable or disable the sidetone, choose your keying mode (iambic A, iambic B, and Ultimatic are supported as well as a straight key mode and a bug mode that simulates a bug style key), choose which side on your paddle is a dit, what frequency the sidetone is sent at, which bank to use for memories, and whether to have the menu send long titles for each menu item.

    It is quite full featured for something that is so small. HamGadgets says that in normal usage the battery that is supplied should last about a year. Within a few seconds of inactivity the microcontroller for the unit goes to sleep to save power, but hitting a button immediately wakes the unit and performs the requested operation. For the end user, the effect is that the unit is always “on” and ready for use while being power efficient.

    It is not without its faults, although the ones I have found are fairly minor. The speaker on the unit is not very loud, especially inside of the provided enclosure. If your primary use is for a code practice oscillator for use without headphones, this may be a problem. I use it as a keyer for my rig, so that isn’t an issue for me, but it is worth noting. The lack of a volume control for headphones may similarly be an issue. The volume is adjustable by changing the soldered capacitor depending on the impedance of the headphones, but it is not able to be changed in normal use. A passive headphone volume control could be added if attenuation is needed. Some users may be unhappy with the default sidetone frequency of 2,000 Hz (700 Hz is the standard for most similar devices). The sidetone can be changed in a menu setting, but the manual suggests keeping it at 2,000 Hz as that is where the supplied speaker has peak loudness. Considering how quiet it is at 2,000 Hz in the case, I’ve elected to keep it where it is, although I do wish it was closer to 700 Hz. That said, when operating my rig, I hear its sidetone through my headphones, so the speaker isn’t necessary for on-the-air usage. The menus are fairly involved, and to use them successfully you must know Morse code as there is no display. That said, the documentation is thorough and easy to follow and if you’re buying a CW keyer, you probably already know or are in the process of learning Morse code, so that’s not likely to be an issue for long. Finally, although long-lived, the reliance on a coin cell battery inside of a case with a screw enclosure means that if the battery dies while away from the shack, it isn’t easy to change in the field.

    I’ve been very pleased with the HamGadgets Ultra PicoKeyer. As a kit, I would say that the Ultra PicoKeyer would be suitable for beginners. If you can make a basic solder joint, this kit is easy to build and hard to mess up. As a keyer, it does a great job in a compact and inexpensive package that is power efficient and easily portable. The memory keying features make it a great companion on-the-air, whether calling CQ, activating a park on POTA, or working a contest. It was fun and quick to build and works well.

  • Morserino-32 (Version 2) Review

    The Morserino is a kit sold by Willi Kraml, OE1WKL of Austria that is a morse trainer, cw keyer, iambic paddle, and an internet and RF connected morse code communications device. It retails for 88 Euros on his website at http://morserino.info and ships to the US in 1-2 weeks with free shipping. It can be used to learn the code, to increase your speed in sending and receiving, to develop the ability for “head copy”, and also as a keyer for a rig that doesn’t have one built-in.

    The Build

    The kit comes well packaged from Austria with everything you need to build it except for a battery. This is because shipping regulations for LiPo batteries can be difficult internationally. Thankfully there are many options available online, including at Amazon.com. All surface mounted components come pre-soldered to the board and all that is left for you to do is to connect the through-hole components. The assembly is relatively straightforward if you have soldered basic electronic kits in the past and the instructions are clear and guide you step-by-step. There are a few 1/8th inch jacks, a power switch, a rotary encoder, a button, a speaker, wiring to the battery you choose, and the headers for the ESP32 MCU that serves as the core of the unit. The kit also comes with an acrylic case that is laser cut and engraved with the logo and labels for the various parts of the kit. I was able to complete the kit in one evening.

    The instructions recommend getting a small LiPo battery to power the unit when it is not connected to a USB power supply, I had several 18650 lithium ion batteries on hand already, so I decided to use one of those instead. The case for the kit does not support such a large battery, however, there is a large active community on the groups.io site for the Morserino, and I found a thread with a link to a 3D printable case that allowed an 18650 battery to be added and kept safely together while still providing access to all the plugs and components. After a quick print on my Prusa i3 MK3S+ in PETG, I had everything together and ready to go. With this battery I’ve been able to run the Morserino for several hours, never coming close to depleting the battery. The battery is easily recharged by plugging the Morserino into USB power. A picture of my build is below. The black case and teal battery and holder are my additions to the setup, everything else comes in the kit.

    Using the Morserino

    The ESP32 MCU comes pre-flashed with the latest Morserino firmware, so you’re ready to go immediately after the kit is assembled. After doing a quick battery calibration with a voltmeter to make the battery graph more accurate (an optional, but recommended step), you are presented with the main menu options: CW Keyer, CW Generator, Echo Trainer, Koch Trainer, Transceiver, CW Decoder, and WiFi Functions.

    The CW Keyer is very useful for sending morse code. Alone it acts as a practice oscillator, but with an appropriate 1/8th inch TRS jack you can connect it up to the key input of your HF rig and use it as an iambic keyer. I have used it for several QSOs using my Kenwood TS-440s that does not have a built-in keyer and it works great. The rotary encoder allows you to select the speed to send the code between 5 and 60 words per minute. The capacitative paddles are surprisingly good and with a bit of practice you can send quite well with a very light touch. With the key input you can also use an external iambic or straight key. I have used my CW Morse Pocket Paddle (a double paddle iambic key) with it and it works very well.

    The CW Generator function generates morse code using different types of output that are played through the speaker (or headphones) and shown on the screen: Random, CW Abbreviations, English Words, Call Signs, Mixed, and a File Player. Random sends random characters. CW Abbreviations shows common terms you’ll hear in a CW QSO. English words selects words randomly from a list of common English words. Call Signs gives a random list of call signs that the system makes up randomly. Mixed takes values from all the other modes and puts them together randomly. Finally, File Player allows you to upload a file to the unit to have it play a script of your choosing.

    The Echo Trainer may well be my favorite feature of the Morserino. It has helped me get faster at decoding and sending morse code. Like the CW Generator, it gives the options of Random, CW Abbreviations, English Words, Call Signs, Mixed, and File Player. The difference is that when it plays you a word, phrase, or random string it does not echo it on the screen. Your task is to decode the word in your head and then use the iambic paddle (either the capacitative one in the kit or your own external key) to send it back to the Morserino. If you sent it properly, it will give you a cheerful beep and show you “OK” on the screen after the letters it decoded from your code. Otherwise you get a buzz and an “ERR” to let you know you got it wrong. After 4 errors, it shows you what the word was and it moves on to the next one. This mode has been the most helpful to me in improving my morse code. I try to spend time every day on the Echo Trainer and have seen consistent progress in my speed and accuracy. More importantly, it is fun.

    There is also a Koch Trainer, which allows you to learn code from the start if you’re not familiar with the letters. It uses the Koch method, starting with 1 character at full speed and going up to 50 (with punctuation and prosigns). Within the trainer there is a CW Generator, Echo Trainer, and a Learn New Character function to learn the new character for that lesson. When you get proficient with the current lesson, you move up to the next, until you’ve learned them all.

    The Transceiver function allows you to send code using the built-in LoRa radio to another Morserino unit. With line of sight, LoRa can go a few kilometers, or even more (there are LoRa satellites that operate in the same low power). One thing of note though, this kit uses the 433 MHz band which is an ISM band in Europe, but not here in the US. As long as you are licensed and ID with your call sign, you can probably use it legally, but not otherwise. The most recent version of the kits come with a dummy load to attach to the antenna connector, which I have connected to it since I don’t have any other units to connect with. The Morserino also supports connecting to the internet over WiFi and there are chat rooms and QSO bots you can connect to if you’re so inclined.

    The CW Decoder works to decode morse from a straight key or from the audio output of a radio. Getting things dialed-in for the radio part can be challenging, but if you get the sidetone to 700 Hz and have a low enough noise floor, decoding is possible.

    Finally, the WiFi Functions menu allows you to find the MAC address for the unit as well as configure your device to connect to your WiFi access point. To get on your network, it first makes its own network you can connect to to type in the SSID and password into a web page. It reboots and is then able to connect. That same page also allows you to specify the address of any chat server or bot site you want to connect to via WiFi. The WiFi Functions menu also gives you the ability to upload files for the CW Generator and to update the firmware over WiFi as well.

    The Morserino has been a great tool for improving my morse code skills. I look forward to sitting down to practice every day and have been seeing steady improvement in my sending and receiving. Since building and practicing with the kit I’ve even gotten on the air and had a few check-ins to MVARC’s weekend Slow Speed Rountdable and logged QSOs with several POTA operators in parks around the country. My goal is to be able to activate a park with POTA using nothing but CW (so far all my activations have been with SSB). If you enjoy building kits and want to improve your morse code skills, I recommend the Morserino. It is fun to build and fun to use.