While cruising Retro Thing, this cardboard tube radio kit caught my eye. It’s available for 49.95 EUR from Conrad International in Germany. I would have never thought about combining the warm character of vacuum tubes with a cardboard chassis. Still, one builder’s report is quite positive and assembly time is estimated at two hours.

Great news for kit builders! Legendary company Heathkit has started manufacturing kits again. Though their first line-up of products do not include radios, they are planning to cater to the amateur radio community as soon as next year.

I would like to believe that the popularity of the Maker community has given Heathkit the ability to re-enter the growing kit building market (it has certainly given Radio Shack reason to continue carrying components).

Here is an announcement from Heathkit’s website:

Thank you for your overwhelming response to our announcement that Heathkit is back into the Do-it-Yourself kits business. We received many great suggestions for kits you would like to build.

We will be releasing Garage Parking Assistant kit (GPA-100) in late September and soon after the Wireless Swimming Pool Monitor kit will be available.

Based on your input, we are looking at developing amateur radio kits. Our goal is to have kits available by the end of year.

Please keep your suggestions coming so that we can continue to bring you interesting, unique Heathkit products.

Now is the time to let Heathkit know you that you want shortwave and amateur radio kits!

You can contact Heathkit at the following address:

Heathkit
2024 Hawthorne Avenue
St. Joseph, MI. 49085
(269) 925-6000 : Phone
(800) 253-0570 : Toll-free
(269) 925-2898 : Fax
info@heathkit.com

In the video below, Alan (W2AEW), shows us the installation and basic operation of an upgraded micro-controller for the Ten Tec Model 1254 Superhet Receiver Kit.

As Alan points out in the video, this is one of two upgrades offered at Cholakian.com. Both upgrades enhance the operation and usability of the Model 1254, giving it many more choices of tuning steps (yes!), the ability to automatically turn off the LED display, more memories and allowing you to eliminate the 9V battery back-up. This basic upgrade costs $38, the premium upgrade costs $68 even allows you to control the receiver via your PC.

Thanks, Alan, for showing us just how simple this upgrade is to perform:

You can see more of Alan’s projects at his website.

A sample illustration from “Making a Transistor Radio”

Those of you who are ham radio operators (especially QRPers) are familiar with the name George Dobbs (G3RJV). In 1972, Reverend Dobbs wrote a book called, Making A Transistor Radio and now it’s available online.

Making A Transistor Radio is a clear, simple, step-by-step guide to building your own transistor radio. In each stage of the process you’re rewarded with a working radio. In addition, you’ll learn about all of the stages of a working receiver.

Perhaps what I love best about this book–besides the fact that is resembles the mountains of electronics books I poured through in my youth–are the illustrations.  Each illustration describes exactly how each component of the radio should be built, leaving nothing to be pondered.

If you’ve ever wanted to build your own radio, from scratch, this is a great place to start.

Thanks, Eric, for sending this link!

Jeffrey Fritz (WB1AAL) contacted me with details about his SDR (Software Defined Radio) “Go Kit” and has kindly allowed me to post it.

Jeff writes:

As a reader of the SWLing blog, I know that you are very interested in SDR. And you probably know that a “Go Kit” is a portable ham radio system in a case that can be moved at a moment’s notice and set up at another moment’s notice virtually anywhere.

I have a VHF Go Kit made up for emergency events. It is complete with waterproof carrying case, Aden PCS-7000H two-meter transceiver, a Kenwood VHF tuner, a Kenwood SW-100 VHF SWR bridge and two antennas (a 2-meter J-pole made out of twin lead and a two meter mag mount.) But what if there is a need to monitor the HF bands during the same event?

Now that I own a Flex-1500 SDR transceiver, the Softrock Ensemble SDR receiver that I bought a while ago has become somewhat redundant. It is still a serviceable radio and works fine, but it can’t hold a candle to the amazing Flex-1500. While I could turn it into a panadapter or sell it on eBay, eHam, etc., I had a better idea.

To monitor the HF ham bands, I could use something like my Grundig G3 shortwave radio in my Go Kit. While it is portable, battery operated and will tune LSB and USB, listening to SSB or even CW in an emergency situation with the G3 can be a bit of a chore. (Think of the old boat anchors with their main tuning and fine tuning band spread dials, but now make both dials tiny and you’ll get the idea.) Instead, why not build a 12-volt battery supply with common, easy to obtain batteries? I could connect it to the Softrock Ensemble and then via a USB audio interface to a battery powered laptop. Add a pair of headphones and we are in business.

That is just what I’ve done.

I’ve attached some photos of my most recent project–done this past weekend actually. [Check out photos above and below] It’s an SDR Go Kit. One of the attached photos shows the laptop and the Softrock Ensemble SDR receiving 40-meter band SSB while entirely being operated on battery power. There is no power switch. You simply pull the DC jack out of the Softrock Ensemble SDR radio when it isn’t in use. Simple as it gets! The other photo shows the battery pack built into a (ahem!) Preparation H Pad holder pack. (Now, I am not saying who used this!)

Ah but what will battery life be like with 8 C cells in series driving the receiver? It’s too soon to say because I just put it together an hour ago. But here’s a guess:

The Softrock Ensemble draws 18 mA at 12.6 volts (my measurement.) An Alkaline ‘C’ battery can supply up to 8,000 mAh, so doing some math and assuming fresh batteries, the battery pack should run the radio for roughly 400 hours. (Hopefully my math is correct!) If so, then I think that the laptop batteries will give out long before the life span of the C Cell is reached!

73,

Jeff, WB1AAL

Jeff, this is an excellent use for the Softrock Ensemble. I imagine it will run for a very long time drawing only 18 mA. I have a “Go Kit” for QRP ham radio purposes and one for SWLing during travels. You’ve inspired me to piece together a proper receiver “Go Kit” to be used in case of emergencies.

Readers: If you have a project, like Jeff, that you’d like to share on the SWLing Post, feel free to contact me with details!

The Spec-Ops Pack-Rat makes for an ideal radio gear bag and easily accommodates the Grundig G3 (Click to enlarge)

As I’ve mentioned before, I love to travel with one bag and efficiently pack my radio gear.

This year at the Dayton Hamvention, my good friend Eric, retiree of the Air National Guard, took me onto the nearby Wright Patterson Air Force Base. Eric is a good buddy and fellow ham, and for several years now, we’ve made it a point to visit both the National Museum of the US Air Force and Wright Patterson AFB while at the Hamvention. This year he was in need of some gear, so we visited the store where those on active duty purchase Air Force-approved gear and clothing. Being a bit of a pack fanatic, I of course quickly found the backpack section. I was searching for the perfect small radio gear pack, and I think I found it: The Spec-Ops Pack-Rat Organizer.

This little pack (roughly the size of a larger-format paperback book at 10″ high, 7.25″ wide x 3″ thick) is built very well–it seems nearly bullet-proof.  It immediately suggested several uses. Here are a few of its advertised features:

• 14 separate storage compartments/ slots
• A unique “inside-out” design which allows for instant open access while inside packs
• 12″ gear-keeper leash for keys, lights, etc.
• Clear business card/ID window
• External mesh pocket
• External accessory loops and carrying handle
• “D”-ring attachment points for optional shoulder strap
• Fully zippered perimeter allows for a 90° opening
• Extremely tough Cordura® 1000D nylon exterior lined with heavy duty nylon pack cloth
• Fully seam-taped interior
• High-tensile nylon web attachment points and
• Bar-tack reinforcements at critical stress points

One glance at the Pack-Rat, and I knew that one of its two largest interior pockets could hold my larger shortwave portables, the other could hold my Kindle Fire tablet, and there would still be plenty of room for wires, cables, accessories, and headphones.

After bringing it home, I was simply amazed at exactly how much gear it could readily hold.  And indeed, this summer I’ve taken it on several trips; including my July trip to Belize for which I packed all of my gear into one small convertible carry-on pack (a small Timbuk2 Wingman).

Here’s the list of items I stashed in the Pack-Rat:

• Grundig G3
• Kindle Fire and power cord
• Zoom H2N microphone with wind screen and mic stand holder
• Eight AA batteries
• Ear buds
• Icom ID-51A HT and adaptor
• 2 Cliff Bars (a guy’s gotta eat!)
• 3′ stereo audio patch cable
• two alligator clip leads
• keys
• pen, pencil, notepad
• business cards

At this point, the little pack was full, but could close very easily and didn’t even bulge on the sides; even with all that (somewhat bulky) gear inside.

Best yet, as I moved around in town, I could use the shoulder strap from my convertible backpack on the Pack-Rat, making it very easy to carry. Even though most of the internal pockets are open from the top, I never had anything fall out, even when the pack was upside down.  When the pack shuts, it seems to put enough pressure on the pockets to hold items securely. It’s bright yellow interior makes it very easy to see the contents even in dim conditions, such as on a night flight.

Spec-Ops packs are made with pride in the USA and obviously meet military standards for durability and construction. They also carry a lifetime warranty. You don’t have to visit a military base to purchase one, either: Spec-Ops has an online store where they carry their full product line. You’ll find the Pack-Rat on this page–note the number of positive reviews from customers.

SWLing Post reader, London Shortwave, is working on a portable SDR (software defined radio) system based on his Toshiba Encore 8″ Windows tablet, FunCube Dongle Pro+, and supported by the excellent SDR# application. Today, he shared this photo of his entire kit, including his comments. If you’re interested in a similar portable SDR, take note of the USB isolator and extra (AA battery) power supply.

London Shortwave plans to make an enclosure for the SDR, AA power supply, and USB isolator.

And although it may be easier said than done, it would be super if this enclosure has the same footprint as the Toshiba tablet, and the whip antenna can be mounted on the enclosure…He would then essentially have a case that he could attach to the tablet for instant portable shortwave radio fun.  (Oops–did I just raise the bar for you? Ha!)

Thanks for sharing, London Shortwave!

Many thanks to the excellent Herculodge blog for making me aware of this cool–nearly retro–Tecsun 2P3 AM Radio Receiver Kit on Amazon.

Should be a fun, inexpensive and relatively simple through-hole kit. I am curious how well the instructions are written in English. Has anyone assembled the Tecsun 2P3?

Update: Bob points out that the Tecsun 2P3 is also available on eBay. (for $26.99 US shipped)

Just learned that David Cripe (NM0S) has a new kit for sale: the Ozark Patrol regenerative receiver kit.

The Ozark Patrol is a simple, straightforward kit, designed with beginners in mind. The kit uses through-hole components, which is to say, mounted on pads etched on the opposite side.  All of the component values and reference numbers are silk-screened on the board to indicate each part’s location, making for truly quick and fool-proof assembly.

What’s more, Dave is a talented kit designer; he’s the brains behind the kit for our successful ETOW HumanaLight (originally conceived by engineer Greg Majewski). He’s not only clever like that, he’s also a great pal.

In the past, when Dave has announced new radio kits for sale, he’s sold out within a few days. That’s why I ordered mine the moment I saw the announcement.

And, hey…not only does just $40 plus shipping ($46 in the US) get you a superb regen receiver kit, but proceeds also support the Four State QRP Group. Win-win, in my book.

Here are a few specifications and design features listed on the Four State QRP Group’s website:

• Frequency Range: 3.5-15 MHz in two bands
• Sensitivity: Yes!
• Power Supply: 6 x AA batteries
• Audio Output: A 2.6” speaker is included, as well as a jack for 1/8” stereo headphones

Want one, too? Click here to order your own Ozark Patrol kit…and enjoy tinkering as well as listening!

Last week, I received the Ozark Patrol regenerative receiver kit that I had only ordered a few days prior. I was so eager to get started on the build, that I read the instructions, lined a cookie sheet with aluminum foil and began placing the parts on the board within an hour of bringing the package home from the post office!

This was my first time building a “Pittsburg” type kit, where through hole components are surface-mounted on soldering pads. It’s a brilliant technique which is very forgiving if the kit builder accidentally mounts the wrong part or mounts a component with the incorrect orientation.

I had hoped to have the kit finished the following day, but other priorities took precedence: I’ve been preparing for my presentation tomorrow at the Pisgah Astronomical Research Institute, preparing a shortwave radio buyer’s guide for the November issue of The Spectrum Monitor magazine, and putting together the results of the Virtual Radio Challenge II (which will be published early next week). Fortunately, I love doing this stuff in my spare time!

I’m eager to pick the Ozark back up early next week and finish the build. It’s become somewhat of a dangling carrot–a reward for finishing other projects in advance. I can’t wait to hear this simple regen receiver come to life!

SWLing Post reader, Chris, writes:

“I just wanted to let you know that I just put together the Tecsun 2P3 AM radio kit over the holiday break. I wanted to also let you know that I made a YouTube review on this radio and some of the short comings on this little radio. I think that some of your readers may be interested also. I have the link below for your review and if you like, you can share it with your readers.”

Many thanks, Chris, for sharing your video! I plan to purchase this kit soon and look forward to referencing your video again and appreciate your advice.

Click here to view Chris’ video on YouTube, or simply watch via the embedded video below:

The Tecsun 2P3 AM radio kit is available from various sellers on eBay–click here to search.

Regular SWLing Post readers know that I’m a sucker for vintage radios––especially those of the WWII era. Indeed, I’m pretty much a fan of anything from the 1930s and 40s. I love the technology of that era and have an affinity for the culture and history, especially film and music.

Last year, I acquired a beautiful Scott Marine Radio Model SLR-M––a receiver that quickly became the centerpiece of my modest vintage radio collection.

Scottie (yep, I call her Scottie) produces beautiful, rich audio from her internal speaker. It’s truly an amazing piece of over-engineered technology that still sounds this good after 70 years.

Edythe Wright

Only a week or so after plugging Scottie into an antenna, my wife and I picked up a $1 CD at a church yard sale. The CD featured big band music from the late 30s/early 40s. Though we already had much of the music on the CD, we bought it anyway to keep in our car. One beautiful fall day, I was driving down a rural road and had the CD playing when a Tommy Dorsey recording of “The Music Goes Round And Round” with Edythe Wright on vocals, began playing. It had been ages since I heard this song…I then wondered how many GIs might have heard this song during WWII via GI Jive or the Armed Forces Radio Network. Perhaps they heard it on the Navy version of my Scott Marine radio, the Navy REH?

It was then I decided to finally pull the trigger and order a proper low-power AM transmitter for our home––something with which I could broadcast period music via my vintage gear.

There are a number of AM transmitters on the market, but the one that always stands out from the crowd is the SSTRAN AMT3000. My buddy, The Professor, has one and uses it to consume much of his digital audio content including podcasts and Internet radio stations. He sang the AMT3000’s praises, and I trust the Prof; he’s something of a medium wave guru.

Thing is, the AMT3000 only ships as a kit. In the past, this had stopped me from ordering the transmitter as I figured it was more than my beginner kit-building skills could manage. But after building David Cripe’s Ozark Patrol regenerative receiver, and loving the experience, I felt confident enough to make the order.

And, boy, am I glad I did!

The SSTRAN AMT3000 kit

The kit arrived within a few days of ordering it. Upon unboxing it, I felt like I had gotten my money’s worth, as it was packaged carefully in a quality box: components were clearly labelled in their own poly bags, the board was clearly marked with component numbers and the assembly/instruction manual was in a plastic binder, all clear and straightforward.

SSTRAN suggests taking your time building the kit, as there are a lot of components to solder, and you risk making mistakes that aren’t necessarily easy to remedy if you rush through the process. I tried to follow this advice––well, I intended to follow this advice. Thing is, I find it very difficult to put down a kit once I’m in the zone, so I zipped along a bit more quickly than I intended.

But it helped that SSTRAN took out a lot of the head-scratching and guesswork; the process couldn’t have been more smooth. I carefully checked and double-checked each component and marked it off the assembly list. First, you install all of the resistors, then capacitors, and on to other components. Other than having to hunt for some of the component locations on the board, it really was quite simple.

I started building the kit on a Friday afternoon and actually finished it the following Saturday morning. Much to my delight, after performing the tuning procedure, the transmitter worked on the first go. Whew!

Powerful (low power) broadcasting

The AMT3000 can be configured to work with the supplied simple wire antenna, which will essentially broadcast AM to radios throughout your home, or it can be configured for a Part 15 compliant outdoor base-loaded vertical antenna which will extend your range up to 3/4 of a mile, should your shack be down the road or in an outbuilding.

For the moment, I have my transmitter set up for in-house broadcasting only.  If I ever want to build the base-loaded vertical, I only need to make a simple modification to the board to do so.

The supplied manual does a great job of explaining the best ways to maximize your signal, reduce any electrical hum and tweak your audio fidelity.

I’ve been using the AMT3000 nearly every day since I finished building it in mid-November. It seems to have a 100% duty cycle, does not overheat, and has no drift.

It produces high fidelity audio with a flat frequency response––and of course, with modulation and compression controls, you can tailor the audio to your particular taste.

Result?  It sounds amazing piping WWII-era tunes through my Scott Marine SLR-M, Hallicrafters SX-24, and SX-99 and my Hammarlund SP-600.

As a bonus, I can hook my shortwave receivers up to the AMT3000 and listen to received audio via other radios throughout my house. Many times, I’ve listened to live broadcasts of ERT Open on 9,420 kHz via my kitchen AM radio…Very cool!

I also hook the AMT3000 up to my shack PC and stream my favorite internet radio station: the UK 1940s Radio Station via TuneIn radio. Absolutely brilliant!

I set my transmitter to 1410 kHz, and have left it there.  You’ll need to do a medium wave (AM) survey to find the clearest spot on your AM dial. I’m sure results will vary, depending on the level of medium wave broadcast activity in your area.

Here’s what my Scott Marine SLR-M sounds like playing “March of the Toys” by Tommy Dorsey and his Orchestra via the SSTRAN AMT3000 (note that this was recorded with just an iPhone, so audio fidelity is somewhat lacking):

Conclusion

If you’re looking for a high-quality, low-power legal AM transmitter, I highly recommend the SSTRAN AMT3000. Even if you’re a novice kit builder, with time and patience, you can successfully construct the AMT3000, too. If I did it, you certainly can!

If you’d prefer buying a pre-assembled AMT3000, they do occasionally turn up on eBay. Click here to search.

As for me, I’m happy to have achieved my modest goal of being able to broadcast 1930s and 1940s music to vintage radios of the same era.

SSTRAN sells the AMT3000 directly on their website. Click here to view.

SSTRAN AMT3000 Models and Prices (via SSTRAN)

AMT3000
10 kHz channel spacing for use inside North and South America. Includes enclosure and 120 Volt AC Adapter. The single surface-mount IC is pre-soldered on the board.
Price: $92.95

AMT3000-9K
9 kHz channel spacing for use outside North and South America. Includes enclosure and 120 Volt AC Adapter. The single surface-mount IC is pre-soldered on the board. *
Price: $92.95

AMT3000-9KNT
Same as AMT3000-9KSM, except the US-standard 120 Volt AC Adapter is not included. **
Price: $88.95

On a tip from my good friend Dave Cripe (NM0S), I just purchased this cute crystal receiver kit from a UK-based seller on eBay.

The price is 8 GPB plus 3.50 GPB for shipping. After PayPal currency conversion, I paid $17.63 US shipped from the UK–a very fair price. The kit is supplied with 5 meters of antenna wire, a high impedence earphone fitted with crocodile clips, and two double crocodile clip leads. Each unit is also tested prior to shipping. The seller also has a 100% positive rating on eBay.

I’ll certainly make a post about the radio once I receive and build it. While there aren’t as many blowtorch broadcast stations to hear these days via a crystal set, with an ample length of antenna wire, you may be surprised what you will hear. Certainly a fun and lightweight item to take camping or place in your bug out bag. No batteries required!

Update: Since making this post, it appears the item number has changed since the seller had to list a new lot of kits.  Below, I’ve made two links that search eBay based on the description, not item number:

• Search via eBay US (best if you’re in the USA, but scroll to bottom of screen to see this item under “International Sellers”)
• Search via eBay UK (best if in UK or EU)

Many thanks to SWLing Post reader, Franz Miller, who writes:

“I’ve pasted a link below to the webpage at Conrad in Germany for yet another Franzis radio kit; no idea how good it is, but it looks neato-retro to me.  Covers longwave, medium, shortwave VHF, & UHF, allegedly.  Price on Conrad’s website is around 69 Euros.”

Click here to view the new Franzis Radio Kit on Conrad’s website.

I truly appreciate the reminder, too, that I have a previous model Franzis kit somewhere in storage that I need to unearth and build! I assume this new Franzis model also has a cardboard chassis.

Update–Tomas adds the following comment:

Here is a link to the Franzis site where there are several pictures and also a two minute video demonstrating the kit.

http://www.franzis.de/elektronik/lernpakete-elektronik/der-grosse-franzis-radiobaukasten#

Of course, for SW it only supports the 41-meter band.

A few weeks ago, we published a short post about a credit card crystal radio from an eBay seller in the UK.

I purchased a kit–at $17-18 US shipped, it’s quite a modest investment for what might be a fun little project.

The crystal radio arrived while I was traveling during Easter break, but my free time has been so (extremely) limited lately, I was only able to unpack and try out this new arrival yesterday.

The biggest surprise for me was the fact that this isn’t really a kit–the board is fully populated and requires no soldering whatsoever. The board feels of very good quality.

All that is required is connecting the high-impedance earphone, earth/ground and aerial/antenna to the board. Since all of these components can be connected with the supplied alligator clip cables, getting it on the air took all of 20 seconds. I simply hooked up the ground and connected the aerial to my sky loop wire antenna.

I instantly heard a signal and station ID which confirmed it was our closest local broadcaster on 1010 kHz.  This station isn’t of the blowtorch variety, but is the strongest one I receive on the MW band simply due to its proximity. Audio was quite faint through the earpiece, but I believe if I tinkered with antenna length and the two variable capacitors, I could improve reception.

SWLing Post reader, Richard Langley, received his crystal radio and had a very similar experience with reception.

With any crystal radio (especially one this small), performance is directly correlated with antenna length, availability of a good ground connection and, of course, strong broadcasters in your vicinity.

I plan to spend an evening tinkering with this little receiver and see if I can pick up some of the night time powerhouse AM stations on the east coast.

I can say this: if you’re looking for a simple, uber-compact emergency receiver for your go-bag, bug out bag or emergency kit, this one will certainly fit the bill. This crystal receiver and all of its components weight no more than a few ounces and could easily fit in compact pouch or sleeve.

Have any other readers have enjoyed tinkering with this little emergency crystal radio?

If you would like to purchase one, try searching eBay with one of the links below. The product will only appear in the search results if currently available.

• Search via eBay US (best if you’re in the USA, but scroll to bottom of screen to see this item under “International Sellers”)
• Search via eBay UK (best if in UK or EU)

(Photo source: Instructables)

SWLing Post contributor, Richard Langley, writes:

Came across this site on building a 3-transistor shortwave radio similar to the kit offered by Radio Shack years ago:

http://www.netzener.net/index.php/8-project-articles/5-3-transistor-short-wave-radio

It was featured on the Instructables site:

http://www.instructables.com/id/Three-Transistor-Short-Wave-Radio/

Very cool!  Thanks for sharing this, Richard.

When I have a little time, I’ll go through my parts box and see how many of these components I already have. The author also supplies an excellent assembly manual for download and print. It would be fantastic if someone would kit up the parts list and offer it as a package. Regardless, this will make for a fun winter project!

My Ozark Patrol regenerative receiver kit

Neil Goldstein, W2NDG, has just informed me that he’s updated his comprehensive radio kit guide which can be found at RadioKitGuide.com. Many thanks, Neil!

The next kit I have on the table is the Sawdust Regenerative Receiver by BreadBoard Radio. Should be a lot of fun and a nice weekend project (once I have a free weekend to complete it). Still, I think I’ll check out Neil’s list to see if there are any new kits I’ve overlooked–after all, fall and winter kit-building seasons are just around the corner!

Many thanks to SWLing Post contributor, Stephen Cooper, who recently shared a video on the SWLing chatroom:

I’m a sucker for cute radio kits, so I purchased one of these from the UK-based seller on eBay as well. There are two kit packages: one with the receiver only, another with the receiver, amplifier and speaker. Shipping is free–even to the US–and pricing is fair (19 – 25 GBP or roughly $30-38 US)

Click here to search eBay.

Readers: if you haven’t checked out the SWLing chat room, I would encourage you to do so! There’s almost always someone there and, many evenings, readers share reception reports in real time. Click here to check out the chat room.

National RF, of California, has introduced a new “semi-kit” receiver: the RF 75-NS-3. Here’s an excerpt from the product description page of the National RF website:

National RF’s 75-NS-3 receiver is a complete super-hetrodyne mini high frequency receiver, designed specifically for the short-wave listener, electronics enthusiast or radio amateur, who wants to use their hands and build a radio. The receiver is offered as a semi-kit in which the electronic assembly is loaded and functionally tested at the National RF facility. The customer must then go to the grocery store (yes…the grocery store!), procure a can of [Spam] lunch meat, eat it or give it to the dog, and then proceed to drill and paint the can, in order for it to become the receiver’s enclosure! […] Detailed drilling instructions and final assembly instructions are provided as part of the kit. All other parts required for completion of the receiver are provided as well. Recognizing that the finished assembly looked somewhat like the fabled Collins receiver of the ‘60s, the 75S-3, (particularly when the can is painted a light gray) National RF engineers dubbed it (with tongue firmly planted in cheek, of course) the 75-NS-3! Although we have had fun packaging this receiver in a lunch meat can, it is nothing to turn your nose at! Its performance and portability will surprise you, and it is an ideal radio to bring with you on any trip!

The receiver architecture is that of a single conversion super-hetrodyne receiver, that is capable of receiving AM, SSB, or CW. The receiver incorporates a dual gate FET as an RF amplifier with manual peaking and gain controls. A ceramic filter is used in the IF section with a front panel switch that controls a broad or narrow IF response. Other front panel controls include audio drive, BFO setting, and a band switch for the HF bands. The 75-NS-3 has internal receive frequency coils that are switched at the front and rear panels. The frequency range of the receiver, over three band set positions, is 3.5 through 12 MHz. This allows reception of several international short-wave bands, the 80, 60, 40, and 30 meter amateur radio bands, and of course, WWV time and frequency standard stations at 5 and 10 MHz.

For those who simply want a lower cost receiver to monitor the shortwave frequencies, National RF offers two variants of the original receiver: the 75-NS-1 and the 75-NS-2. Both are based on the design and circuit of the 75-NS-3, but do not have the band switching and frequency range of the 75-NS-3 receiver. The 75-NS-1 covers between 3 and 6 MHz, including the 80 and 60 meter amateur band. The 75-NS-2 covers between 6 and 12 MHz, including the 40 and 30 meter amateur bands. Both units have the fixed ceramic resonator band width set for about 6 KHz. And, of course, they are both designed to fit in the tasty potted meat can!! All other specifications presented apply to both of these models as well.

Pricing of the 75-NS-x versions:

• Type 75-NS-1 Mini HF Receiver Semi-kit (covers 3 to 6 MHz) $189.95
• Type 75-NS-2 Mini HF Receiver Semi-kit (6 to 12 MHz) $189.95
• Type 75-NS-3 Mini HF Receiver Semi-kit (band switched from 3.5 through 12 MHz in three switched positions) $269.95
• Shipping and Handling to within the US $10.00 each

Click here to view on the National RF website.

The Heathkit Explorer Jr. (Image Source: Heathkit)

Yes, the legendary Heathkit company is back and their first kit is a simple Tuned Radio Frequency (TRF) AM/mediumwave analog receiver: the Explorer Jr.

I knew Heathkit was back in business and under new management, but hadn’t heard any updates as of late. Their president, Andy, just sent a message to the “Heathkit Insiders” group explaining what the team has been up to:

“We’ve designed and developed a wide range of entirely new kit products. We authored the manuals for these kits, complete with the beautiful line art you rely on, preserving and respecting our iconic historic Heathkit style. We developed many new inventions and filed patents on them. We relocated Heathkit, and set up a factory, and a warehouse, and offices, in Santa Cruz, California, near Silicon Valley. We built the back office infrastructure, vendor and supply chain relationships, systems, procedures, operations methods, and well-thought-out corporate structure that a manufacturing company needs to support its customers, to allow us to scale instantly the day we resume major kit sales. All this effort enables us to introduce a fleet of new kits and helps ensure Heathkit can grow, prosper, and continue to bring you great new products for a very long time.”

The Insiders’ message goes into much more detail–I would encourage you to contact Heathkit about joining this group.

The big news in this message was the launch announcement of the Explorer Jr. kit which can be ordered from their website now. The price is $149.95 plus shipping. Heathkit anticipates a 30-day shipping time for the first set of orders.

Here’s a description of the kit from their website: