Most of our readers are quite familiar with Heathkits, since starting in 1947, the Heath Company sold kits for a wide variety of electronic devices. But the company actually got its start in 1926 with the product shown here, a Heathkit airplane, namely, the Heath Parasol. About a thousand of the kits were sold in the late 1920s and early 1930s.
The ad here appeared 90 years ago this month in the January 1931 issue of Popular Mechanics.
Eighty years ago this month, the January 1941 issue of Radio Retailing carried this ad showing the 1941 lineup from Sonora Radio. With one exception, all of the sets shown cover the broadcast band only. Two are portables, and one, the model KNF-148 also includes a phonograph.
The six-tube model KXF-95 was a console which also tuned shortwave and included a phonograph. The company was based at 2626 Washington Blvd., Chicago.
Eighty years ago this month, someone wrote in to the January 1941 issue of Radio & Television
magazine requesting plans for a one-tube set which would cover the broadcast bands and the shortwaves. The editors obliged with this simple circuit.
Coil winding data was included, and the editors noted that with the capacitor shown, one coil would cover the entire broadcast band. On the shortwaves, they noted that tuning would be very sharp, and recommended a smaller bandspread capacitor in parallel with the main tuning.
Sixty years ago this month, the January 1961 issue of Electronics World carried this ad for the Hallicrafters HT-40 transmitter and SX-140 receiver for the 80-6 meter amateur bands. They were available assembled or in kit form. As a kit, the transmitter retailed for $79.95, and the receiver, $94.95. Assembled, the prices were $99.95 for the transmitter and $109.95 for the receiver.
The five-tube receiver was billed as the lowest-priced amateur band receiver available. The transmitter had a DC input power of 75 watts to a 6DQ5 power amplifier, with a 6CX8 serving as crystal oscillator and driver. For AM, it used a 12AX7 audio amplifier and 6DE7 modulator. Both units featured silicon high voltage rectifiers.
I’ve never seen the receiver in operation, but the HT-40 was my first transmitter as a novice, and I used it to burn up the ether on 40 meters in 1974. I used that transmitter for my first few months as a novice before upgrading to a Viking Ranger with VFO. When the transmitter first came out, novices were limited to crystal control, and it made an ideal novice rig. When the licensee upgraded to general (or even technician, thanks to the presence of 6 meters), the new licensee could get right to work on AM.
As promised, here are the answers to yesterday’s quiz, from the January 1971 issue of Popular Electronics.
The one on the left is 12 pF. The center one is 6 pF, and the one on the right is 10 pF.
This quiz appeared in Popular Electronics 50 years ago this month, January 1971. With a little bit of re-drawing and some basic math, you should be able to come up with the answers. If not, we’ll post them here tomorrow.
Sixty years ago this month, the January 1961 issue of Electronics Illustrated showed this automotive record player, the Norelco “Auto Mignon” (sold in Europe under the Philips name).
The set played 45 RPM records, which were loaded from the front with a “trap door,” not unlike how CD’s are loaded into most car players. The set played through the car radio, and ran off either 6 or12 volts. It retailed for $57.50
You can see a well preserved specimen of the model in this video:
Shown here as it appeared 80 years ago is the service shop of Sam Tagart, who had recently moved his shop to this fine modern store at 37th & W. North Avenue, Milwaukee.
The move to a prime location was made possible by direct mail advertising. The January 1941 issue of Radio Service Dealer reported that Tagart started out by mailing 250 direct mail ads four times per year to radio set owners, along with occasional mailings to radio dealers. At first, he got a return of about 10%, which worked its way up to 20%. He had recently increased his mailings to 1200 each time.
Part of his success was the spic-and-span shop shown here. He worked on sets in view of his customers, and many regular customers came from those who watched him work. Above his workbench is a mirror, which allows him to easily keep an eye on the front of the store.
The building that housed Tagart’s shop is no longer standing, but the building next door is. There’s now a Citgo gas station where that shop once stood:
This utilitarian-looking receiver appeared fifty years ago this month in the January 1971 issue of the British Radio Constructor magazine. Complete with its own coat of arms, the set was dubbed the Crusader, and tuned longwave (150-375 kHz), mediumwave (545-1546 kHz), and shortwave (1.85-18.75 MHz). Even though it was billed as being for the near beginner, the 6-tube set was a superheterodyne, and probably did an admirable job of pulling in the weak stations. Construction was simplified by the pre-assembled coil pack, which is undoubtedly unobtainium today. It featured a transformer power supply, making it a safe set to operate from the AC mains.
Seventy years ago, it was a pretty good bet that a Boy Scout would have an interest in radio, so the “Hobby Corner” feature of Boys’ Life, January 1951, offered some pointers for a Scout on how to up an aerial.
The magazine noted that if you had a crystal set or a one-tube radio, then a good antenna would ensure good reception. It recommended a run of about 50-100 feet of copper wire, with glass insulators carefully placed at either end. Because the wire would contract in cold weather, some slack was called for. To avoid noise, the antenna should not be parallel to power lines, “and don’t throw antenna wire over power lines–it’s dangerous.”