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Handie-Talkie or Walkie-Talkie?

By: Bob K0NR
22 September 2024 at 23:47
The Motorola HT-220 Handie-Talkie

In ham radio, we often use Handie-Talkie or HT to describe a compact, handheld transceiver. My first exposure to the term Handie-Talkie was when I became a licensed radio amateur in 1977. As a student at Purdue University (W9YB), the absolute coolest VHF radio to have was the Motorola HT-220. Even a used one commanded a high price so they were out of my price range and I never owned one. These were 6-channel crystal-controlled transceivers…back then you had to set up the radio with the particular 2m frequencies you wanted to use. Because it was such an iconic radio, there are many HT-220 enthusiasts still around with websites with tons of useful information. See the HT-220 Page.

Motorola trademarked the name Handie-Talkie and used that nomenclature for many years with its line of portable radios. However, this trademark has expired, so now Handie-Talkie is a generic term.

The First Handie-Talkie

But the HT-220 was not the first Handie-Talkie, so I started poking around to find out how this name originated. Back in World War II, the SCR-536 was a portable β€œhand-held” transceiver developed in 1940 by Galvin Manufacturing (later Motorola, Inc.)Β  I put β€œhand-held” in quotes because, by today’s standards, it was a Hand FULL. But most people consider the SCR-536 to be the first modern, self-contained HT transceiver. The Wikipedia article for the SCR-536 describes the radio quite well. The radio put out about 360 mW of RF power on 3.5 and 6.0 MHz (Oops, I mean 3500 to 6000 kilocycles) using Amplitude Modulation (AM). The circuitry relied on smallish vacuum tubes, creating quite a design challenge. Motorola has a page on its website that talks about the origins of the radio. IEEE Spectrum also published an excellent article: The SCR-536 Handie-Talkie Was the Modern Walkie-Talkie’s Finicky Ancestor. The January 2005 issue of QST has an interesting article by Gil McElroy, VE3PKD, A Short History of the Handheld Transceiver. It provides more history and insight into this fun topic.

The SCR-536 Handie-Talkie

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The First Walkie-Talkie

A few years later (1942), a backpack portable radio was introduced, called the SCR-300. I always assumed that the backpack-style radio would have come first and the more compact radio SCR-536 would be later. (Actually, there were previous backpack radios, such as the SCR-194). This new backpack-style radio was referred to as a Walkie-Talkie. According to the manual, the SCR-300 was β€œprimarily intended as a walkie-talkie for foot combat troops”. I suppose the emphasis was on how you can walk and talk, with a radio on your back.

The SCR-300 Walkie-Talkie transceiver.

This article: SCR-300 WW2 Radio Backpack: The β€œWalkie Talkie” That Shaped the War describes this radio as a game-changer for frontline troops. The radio weighed a heavy 35 pounds, and used Frequency Modulation (FM) on 40 to 48 Megacycles.

Of course, with technology development, there is always the question of β€œwho was first”? The SCR-194 that predated the SCR-300 might be considered the first walkie-talkie. However, the SCR-300 and the SCR-536 seem to get all of the glory, probably due to their impact on the war effort. However, take a look here if you want to dig deeper: TALK the WALK or WALK the TALK: Who actually developed the first Walkie-Talkie?

This article describes the development and use of the SCR-300 and mentions some of the limitations of the SCR-194: SCR-300 History Development Employment and Details Final Draft This is a big file with many photos but worth reading if you have the time.

Today’s Terminology

The Yaesu FT-4X handheld transceiver

Fast forward to today and we see that the HT and Handie-Talkie nomenclature is common in the amateur radio world. The photo to the left shows a modern 2m/70cm HT, the Yaesu FT-4X.

The term β€œwalkie-talkie” has morphed to something quite different and is used generically to describe a handheld radio. This term covers a wide range of radios, from low-cost Family Radio Service (FRS) radios to higher-quality professional radios. This is quite different from the original Walkie-Talkie, a backpack radio weighing 35 pounds.

The military has progressed with improved communication technology, still using backpack-style radios, now referred to as manpack radios. These are amazing radios that pack extensive capability into a relatively small package. The AN/PR-158 shown below covers 30 to 2500 MHz in frequency, satellite comms, advanced encryption, narrowband and wideband modes: AM, ASK, FM, FSK, PSK, CPM, GMSK, and plenty more. This radio weighs 12.7 pounds with the battery installed, so a lot lighter than the old SCR-300.

A modern military manpack radio (AN/PR-158)

So that’s a quick tour through some radio terminology along with a bit of historical perspective. I discovered there is an infinite supply of information out there on the history and technology of military radios. If you want to dig deeper, go for it!

73 Bob K0NR

The post Handie-Talkie or Walkie-Talkie? appeared first on The KØNR Radio Site.

Common Ham Shack Radio Configurations

By: Bob K0NR
14 April 2024 at 23:54

Amateur radio transceivers have improved dramatically over the decades and they pack a lot of capability into relatively compact radios. In this post, we will take a look at the typical configurations and how they may impact setting up a flexible amateur radio station today. This discussion is focused on currently available new gear, with 50 to 100 watts of RF power.

The Kenwood TS-430S was a popular HF transceiver in the 1980s.

The most common HF radio configuration used to be a 5-band model that offered CW, AM, and SSB on 80 meters, 40 meters, 20 meters, 15 meters, and 10 meters. In the early 1980s, the WARC bands were added (named for the World Administrative Radio Conference of 1979) that authorized these new bands. The WARC bands are 30 meters, 17 meters, and 12 meters. These attractive new bands were soon added to the standard HF rig.Β  Most HF radios include 160 meters (actually a Medium Frequency or MF band) on the low end and a general coverage receiver for 150 kHz to 30 MHz. So these days, the typical HF transceiver handles 9 bands and many different modes. (Actually, most of these rigs now include 6 meters, more on that later.)

Dominant Design

In the world of product development, the concept of a dominant design often emerges. This generally accepted approach dominates a particular market and is considered the standard way of doing things in a particular product category.

From Wikipedia:

Dominant design is a technology management concept introduced by James M. Utterback and William J. Abernathy in 1975, identifying key technological features that become a de facto standard. A dominant design is the one that wins the allegiance of the marketplace, the one to which competitors and innovators must adhere if they hope to command significant market following.

We will see that most ham radio gear conforms to the concept of a dominant design. That is, certain product configurations become standard, especially in terms of frequency bands and modes. Manufacturers still innovate by adding new features in an attempt to differentiate and obtain competitive advantage but the basic capabilities are standard. The dominant design for HF transceivers is the 100-watt radio that covers 160m through 6m.

VHF/UHF Radios

For VHF/UHF, the situation is a bit more scattered. 2-meter FM is the most popular band and back in the olden days, it was common to just have a single-band 2m FM rig in the shack. To cover 70 cm FM, a radio ham needed a second radio but later dual-band radios showed up that covered 2m and 70 cm. Today, the dominant design for VHF/UHF is the dual-band FM transceiver (typically 50 watts of output power) and there are so many of these available I won’t attempt to list them.

The IC-2730A is a basic 2m and 70cm transceiver with dual receivers.

VHF FM is the utility mode for amateur radio and many hams are just fine using FM (or one of the digital voice modes) on VHF/UHF. Those who want to stretch the limits of VHF/UHF operating usually go for all-mode rigs that offer CW, SSB, FM and various WSJT digital modes. Again, back in the olden days, a VHF+ enthusiast would acquire single-band all-mode radios for the bands of interest. A ham really into VHF/UHF might have single-band radios for 6m, 2m, 1.25m, and 70 cm stacked up in the ham shack. The 1.25-meter band has always been a bit neglected in terms of equipment availability because that band is not available worldwide. Transverters are another option to get all-mode capability on these bands using an HF transceiver to transvert to a single VHF or UHF band.

HF Plus 6 Meters

One important addition to the standard HF rig is that the 6m band is often included. Now this may not sound quite right because we all know that 6 meters is a VHF band, so what is it doing in an HF radio? It actually makes a lot of sense because a lot of 6-meter operating is similar to HF. (6 meters is the VHF band that often emulates HF.) There is FM activity on 6 meters but most of the action is on SSB, CW, and, yes, FT8. In fact, FT8 is seeing a lot of action on the band, so if you want to participate on 6m, you should consider that mode. Anyway, this all means you probably need an all-mode radio for 6 meters, and having it as a bonus band on an HF radio without a huge increase in cost is a good approach. (These radios usually support FM for the 10m and 6m bands.)

The IC-7300 transceiver covers all the HF bands and 6 meters (50 MHz).

There are many great HF/6m radios to choose from so I won’t try to list them all. Some of the more popular ones in the $1k to $1.5k range are: Icom IC-7300, Yaesu FT-710, and Yaesu FT-DX10.

All-Band All-Mode Rigs

Another common transceiver configuration is the All-Band All-Mode radio available from several manufacturers. A great example of this type of radio is the Yaesu FT-991A, which includes 160m through 10m plus 6m, 2m, and 70cm. Once again, 1.25m is passed over. This radio configuration has a lot of appeal because it covers pretty much everything with all-mode capability. (It also has a built-in sound card and USB connection which is handy for the WSJT digital modes.)

The Yaesu FT-991A covers 160m through 10m, plus 6m, 2m and 70cm.

The FT-991A is a good choice for the ham shack or operating portable but it is a bit large for a mobile installation. Icom offers the IC-7100 in a mobile form factor, with a novel sloping detachable front panel. Yaesu used to offer mobile products in this space such as the very popular FT-857D transceiver. However, the FT-857D is no longer made and its apparent replacement is the FT-891 which has only the HF + 6m bands.

The Icom IC-7100 is a mobile rig with HF, 6m, 2m, and 70 cm.

The main disadvantage of this type of radio is that it can only do one frequency at a time. Often, I want to be able to work HF while still monitoring the local 2m FM repeater and simplex channels. Or maybe I’d like to keep listening for 6 meter activity while working 2m SSB, especially during a contest. However, this type of radio is my first choice for portable operating for Parks On The Air because it covers all the bands and modes. This article is focused on 100-watt radios but note that there are all-mode all-band QRP radios such as the IC-705.

All Mode VHF/UHF Radios

One interesting and disappointing trend that has emerged is the distinct lack of VHF/UHF all-mode transceivers. There is only one such radio on the market today, the Icom IC-9700 which does all modes on 2m, 70cm, and 23 cm (1.2 GHz). It seems that Icom decided that if they are going to offer a VHF/UHF radio, they would go full-featured and include 23 cm. Note that if you pair this radio with an HF plus 6m radio, you can cover all the popular bands with all modes using two radios. This radio is not inexpensive, currently selling new for about $1800.

The Icom IC-9700 is a VHF/UHF transceiver that offers all modes on 2m, 70cm and 23cm.

I suppose we can declare this the dominant design for VHF/UHF but it is a lone product in this space. I have written previously about an all-mode dual-band portable radio for 2m/70cm that I desire. I own an IC-9700 and like it a lot but I would give up the 23 cm band to have a radio that is more portable and less expensive. I suspect that Icom is happily making good profit margins on the IC-9700 given that they have essentially no competition in this space. Yaesu has the technology to do something here but has been content to let the FT-991A cover the all-mode 2m/70cm space for them.

Common Ham Shack Setups

Now let’s take a look at some common ham shack configurations that consider these different radio configurations. When I say β€œham shack” that may include your mobile or portable station, too.

Setup 1: FM VHF/UHF Only A Technician might decide they want to focus on 2m and 70cm, with FM being just fine for working simplex and repeaters on those bands. A basic dual-band FM transceiver will handle this nicely, see A VHF FM Station at Home. For some hams, their dual-band handheld radio serves this purpose.

Setup 2: All-Band All-Mode Transceiver As mentioned earlier, All-Band All-Mode radios cover the most popular ham bands and modes with one rig. They are a good way to get one radio that does everything. The disadvantage is not being able to monitor VHF/UHF at the same time as working HF.

Setup 3: HF/6m radio plus 2m/70cm FM radio This is a very common configuration for a ham shack because it separates the HF bands (and 6m) from the 2m/70cm FM operating. The FM rig can be left monitoring your favorite repeater or simplex frequency while you chase DX on 15 meters. If your 2m/70cm needs are basic, the FM radio might even be a handheld transceiver.

Setup 4: HF/6m radio plus all-mode VHF/UHF radio This is the setup for the ham that wants to cover all the bands and be able to do all modes on VHF/UHF. The band/mode coverage is similar to Setup 2 but we have two radios available which provides the monitoring flexibility associated with Setup 3. This configuration allows for having a really good HF/6m radio and a really good VHF/UHF radio.

Conclusions

The ham radio transceivers being offered tend to follow certain patterns consistent with the dominant design theory. If you buy a modern HF transceiver, you will likely get all of the HF bands plus the 6m bonus band. These radios vary in features and performance but they all have good band/mode coverage. The VHF/UHF situation is perhaps not quite as simple. The standard 2m/70cm FM rig is a popular option but is limited to FM only. The VHF/UHF weak-signal enthusiast does not have many choices beyond the IC-9700, which may represent an opportunity for another manufacturer to jump in with a more cost-effective 2m/70cm all-mode radio. The 1.25m band continues to be neglected and may be a good additional band to add to 2m/70cm radios.

That’s my analysis. What do you think?

73 Bob K0NR

The post Common Ham Shack Radio Configurations appeared first on The KØNR Radio Site.

An Easy HF Antenna

By: Bob K0NR
15 January 2024 at 18:04

When radio amateurs get ready to put an HF station on the air, they often have questions about what antenna to use. The good news is that there are many options to choose from. The bad news is that there are too many options to choose from. It can be overwhelming. This post describes an antenna I just installed that is easy to put up and works well.

The ponderosa pine tree supports the endfed wire antenna.

Having 30-foot tall pine trees on our property, my usual approach for HF antennas is β€œwires in the trees.” I have several ropes strung up over these tall trees so that I can raise and lower wire antennas as needed. These ropes were installed using a slingshot to launch a fishing line over the top of the tree, then I pulled up a lightweight rope.

The 9:1 UNUN provides the matching at the end of the wire antenna.

End Fed Long Wire

The antenna is the EFLW-1K from MyAntennas.com, which is an End Fed Long Wire Antenna. (This should not be confused with an End Fed Half Wave antenna.) This antenna is intentionally cut to not be a resonant length on any of the bands. The 9:1 UNUN transforms the high impedance at the end of the wire down to something closer to 50 ohms. The match is not perfect so an antenna tuner is required to cover all of the bands. MyAntennas offers this antenna with different lengths of wire, with longer wires required to support the lower HF bands. I purchased the 53-foot version but decided to shorten the wire. My interest is working 20 meters and higher and I wanted the antenna to be mostly vertical, so I shortened the wire to 36 feet. The MyAntennas products are good but other similar 9:1 UNUN products on the end of a wire will work.

An endfed antenna like this needs some kind of counterpoise to balance out the antenna operation. Many people have written about this and there are many different approaches. The MyAntenna UNUN has a connector intended to support adding a short length of counterpoise wire. I could have gone that route but a decent length of coaxial cable lying on the ground can function as this counterpoise. So that’s what I decided to use.

The B11ISO isolation transformer is inserted in line with the coaxial cable.

I also added an inline isolation transformer to minimize the common mode currents getting back to the transceiver. I don’t know that this is required but I had one available so I used it. The antenna has 50 feet of LMR 400 coax laying on the ground which connects to the inline transformer. Then, another 25 feet of RG-8X coax connects the transformer to my transceiver. The internal antenna tuner in my Icom IC-7610 handles this antenna quite well, tuning up on 20m, 17m, 15m, 12m and 10m. This means I can instantly switch between the bands and be ready to go.

I’ve been running SSB, FT8 and FT4 on this antenna, working many stations in all regions: Europe, Asia, Oceania, Africa, North and South America. Conditions are great and I keep telling newer folks: now is the time to be on HF! This basic antenna is a great way to get on the air and work some DX.

73 Bob K0NR

Update (18 Jan 2024): I gave this antenna a try on 6 meters using the IC-7610 (with tuner) and it works on that band, too.
Update (05 Feb 2024): Just for fun, I tried the antenna on 30m and 40m. I thought it would be too short but the tuner in the IC-7610 was happy and I am making contacts on those two bands.

The post An Easy HF Antenna appeared first on The KØNR Radio Site.

Improved IC-705 SOTA/POTA station

By: Bob K0NR
28 September 2023 at 17:22

This past year, Joyce/\K0JJW and I did quite a few Summits On The Air (SOTA) and Parks On The Air (POTA) activations, often as part of an RV camping trip. During this time, we made some improvements to our portable gear. For SOTA, we primarily use the VHF/UHF bands but we have been sprinkling in a bit more HF activity. For POTA, we often don’t have a Height Above Average Terrain advantage, so we definitely use the HF bands.

The ICOM IC-705 is a great backpack portable rig for SOTA and POTA.

Our main goal was to have a backpack portable station for SOTA and POTA that can cover HF through 70 cm, on the most popular bands/modes including CW, SSB, FM and FT8.

Using The IC-705

Bioenno Power Battery
This 4.5 Ah battery from Bioenno is a compact, lightweight battery for portable operating.

The Icom IC-705 is a great transceiver for covering most HF, VHF and UHF bands. With an external battery, the transceiver puts out 10 watts of RF power. (This is a bit less than the 50 watts from our Yaesu FT-90, which is our default choice for 2m and 70 cm SOTA.) We have accumulated a number of Lithium Iron Phosphate batteries from Bioenno. They are all set up with PowerPole connectors and are easily interchanged. See a previous post, My SOTA Battery Journey.

Arguably the biggest weakness of the IC-705 is the lack of an internal antenna tuner for the HF bands. Of course, you can operate without a tuner by making sure your antenna is always 50 ohms. I find that limiting, especially under portable conditions where the antenna configuration might be compromised. Also, some common end-fed antennas that cover multiple bands are not a good match for all bands. There are external automatic antenna tuners available for the IC-705, so initially those looked like a good solution. Then I remembered that I had a small MFJ-902 Travel Tuner that could do the job. The MFJ-902 is a classic T-network with two variable capacitors and one variable inductor. I gave it a try and was impressed with how easy it was to tune using the SWR meter of the IC-705. This thing is simple and it works.

The MFJ-902 Travel Tuner is a simple T-network antenna tuner.

The rear panel of the tuner has two SO-239 connectors, one for the transceiver and one for the antenna. I put a BNC adapter onto the transceiver port and used a short BNC cable to connect to the IC-705.

The rear panel of the Travel Tuner, with an SO-239-to-BNC adapter installed.
A typical picnic table setup using the IC-705 with the MFJ-902 tuner.

The Travel Tuner is compact and not very heavy, so it works out well for backpack portable use. It can handle up to 150 watts, which is overkill for the IC-705 but it may come in handy when used with a higher power transceiver. Still, I am on the lookout for an even more compact (probably lower power) manual antenna tuner.

A typical end-fed half-wave wire antenna for 15 meters.

We have collected a variety of HF antennas, focused mostly on 20 meters and higher. These are typically end-fed, including single-band half-wave designs as well as multiband random-length antennas. These are used in the classic SOTA configuration with one end of the wire supported by a lightweight fishing pole and the coax connection on the ground, fed by a 25-foot length of RG-8X coaxial cable.

FT8 Solution

With the popularity of FT8 on the HF bands as well as 6 meters, I figured we should include that mode in our portable kit. My first thought was to use a compact Windows computer running the standard WSJT-X software. Ultimately, I chose the SDR Control app for the Apple iPad (by Marcus/DL8MRE), which supports specific Icom radios. The iPad connects to the IC-705 via its WiFi connection, which simplifies the connection/cabling challenge. The SDR Control app does cost $49.99, so it is not your inexpensive iOS app but I have found it to be worth the price. Because this app is focused only on iOS and certain Icom radios, it is well-tuned to be a no-fuss solution. I am currently using the app only for FT8 but it has other features and modes for me to explore.

The portable station for FT8, running SDR Control on an iPad.

The Powerwerx PWRbox is shown in the photo above, which we often use for operating POTA. (This box is a bit heavy for hiking.) The PWRbox holds a 20 Ah battery as described here. Also shown in the photo is a handy little stand for the IC-705, the NEEWER Folding Z Flex Tilt Head. It does a great job of holding and stabilizing the radio at a variety of angles. (Hat tip to Kyle/KD0TRD.) It is also a little heavy for backpack portable, so it usually gets left behind on a hike.

The Maxpedition bottle holder case works well with the IC-705.

For a protective case for the IC-705, we use the Maxpedition 12-Inch X 5-Inch Bottle Holder. I’ve seen other IC-705 users recommend it and OH8STN mentioned it on his blog. At first glance, the case seems a bit large but this provides enough room inside to stow a small Bioenno battery and other accessories. The side pouch is a good place for storing the microphone and power cord.

Wrap Up

This post shares some new equipment configurations we are using for SOTA and POTA, mostly focused on the IC-705. I really like that radio for portable ops as it is the best solution for operating HF through UHF. The SDR Control software on an iPad has also turned out to be a win for us.

What are you using for your portable station?
Do you have any tips or other operating ideas?

73 Bob K0NR

The post Improved IC-705 SOTA/POTA station appeared first on The KØNR Radio Site.

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