Seventy-five years ago this month, the September 1947 issue of Radio Craft sang the praises of the Pilotuner model T-601 FM tuner, designed to cover the new FM band. The set had audio output, so could be plugged into the phono jack of a standard broadcast radio or into a phonograph. Priced at only $29.95, it was predicted to be the thing to bring FM out of the luxury class and make it available to the average man.

Those with prewar FM sets that covered 42-49 MHz could simply add the new tuner without making “complicated and costly conversions.” It had a built-in antenna that could be used in strong signal areas, and it had provision for hooking up an external antenna.

It had a power transformer, which was an important feature, since it was isolated from the power line. This meant that it could be hooked to an AC-DC set without having to worry about polarity.

In tests in downtown Manhattan, the set functioned well with the built-in antenna, with no signs of frequency drift. Two strong stations separated by only two channels (in other words, 400 kHz) were easily separated.

Seventy years ago this month, the September 1952 issue of Radio-Electronics carried the plans for this miniature regenerative receiver covering three bands with the convenience of band switching. The coil was wound by the builder, and different windings were switched in to cover the broadcast band, 1.5-4 MHz, and 6-16 MHz. The set was 7.5 inches deep, 6 inches long, and 1.5 inches high, and housed a 7H7 regenerative detector, with the audio being amplified by a 6SQ7 and 6F6. It was billed as being suitable for “signal monitoring, dial-twirling, or emergency standby service.” In addition to 6.3 volts for the filaments, the set required a power supply of 180-250 VDC.

Shown here is Dr. Ralph W. Davis (left), chief surgeon at Audubon Hospital, Audubon, N.J. He is shown with Max Joseph Bonsted, W2EQ, who facilitated a transoceanic medical consultation. An unidentified soldier was dying of injuries sustained in a plane crash, on Palmyra Island, 6000 miles away. There was no doctor on the island, so a government weather observer used his amateur radio to contact Bonsted. The men treating the soldier followed Dr. Davis’ instructions, and they reported back that he seemed to be improving.

The photo appeared 75 years ago this month in the September 1947 issue of Radio News.

A hundred years ago this month, the September 1922 issue of Popular Mechanics showed how to make this radio transmitter. According to the author, F.L. Brittin, the set was capable of distances of up to 16 miles, and relied upon an automobile ignition coil to generate the high voltage for the spark. It was small enough to put in a small suitcase, and “well adjusted to the needs of outers in motor cars or boats, and for boy-scout field work.”

If parts were bought new, the cost was about $15, but by using materials commonly available around the shop, this could be reduced.

The magazine reminded readers that a license was necessary before transmitting, and full details could be obtained from the radio inspector in the builder’s district.

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Sixty years ago this month, under the headline “Soldering Savvy,” the September 1962 issue of Popular Mechanics offered this self-explanatory helpful hint. Of course, it was taken for granted that you should wear a tie when soldering, so they don’t even mention that. The hint was to just hold the solder between your teeth if you need both of your hands to do the job.

While, chances are, no harm was done, solder contains lead, and it’s generally not a good idea to ingest lead, even in small quantities. So putting it in your mouth, or even eating a sandwich after soldering, probably isn’t a good idea, and we don’t recommend it.

Fortunately, you no longer need to do this, since you can get one of the handy gadgets here to hold your work while you use one hand to hold the iron, and the other hand to hold the solder. It makes life a lot easier, and you don’t have to worry about lead poisoning.

And while were at it, this guy’s boss would probably get fined a few million dollars today by OSHA. In addition to wearing a tie that might get caught in machinery, he’s not wearing any safety glasses. Occasionally, little bits of hot resin, or even molten lead, go flying when you’re soldering, and it would be a bad thing if one of them landed in your eye. So, invest a couple of bucks in a pair of safety glasses or goggles. As with everything, you can find all of these things at Amazon:

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This gentleman, shown 85 years ago this month in the September 1937 issue of Popular Science, might be listening to a standard broadcast program. But chances are, he’s tuning the longwaves, listening to ships or aircraft beacons on what was then called the X-Band (not to be confused with the modern X band of 7-11.2 GHz, or the expanded AM broadcast band of 1610-1700 kHz).

The set used two tubes to cover 250-1650 kHz in two bands, with a tapped coil and a toggle switch to short out part of the coil for the higher frequencies. The circuit could be duplicated today, since there don’t appear to be any unobtainium parts. You wound the coil yourself, although it would take a bit of patience, since it consisted of 360 turns of number 32 wire carefully wound on a 1-1/4″ form.

Government weather reports were easy to tune in with the set, since they were transmitted on the A-N beacon frequencies. If you lived right on an airway, you would hear a continuous carrier. But more likely, you would hear either an A or an N in Morse code, indicating you were off to one side. Once a minute the station would send its call letters. Weather reports were broadcast on a regular basis.

In addition, lighthouse radio beacons consisted of one letter repeated for one minute. These were in clusters of three stations, and they would take turns sending a letter, allowing a ship radio compass to determine its position.

The article warned that, like all regenerative detectors, the set was capable of interfering with nearby receivers if improperly tuned. To avoid this, the article advised tuning in from the edge of the signal, and turning down the regeneration before tuning in the exact carrier frequency.

The nondescript black box shown here is a longwave receiver from the September 1942 issue of Radio News.  (The instrument at the left is an Aerovox L-C checker, presumably there to show the scale.) Specifically, the receiver was part of the broadcast equipment of WCED radio in Pennsylvania, and was designed to pull in the time signals from the Naval Observatory from station NSS, Annapolis, MD, operating on 113 kHz. For a station in a place like Pennsylvania, just a few hundred miles from Annapolis, the shortwave signals were often unreliable, being in the skip zone. The longwave signals were reliable, with no fading. The Navy permitted their rebroadcast by local stations, on the condition that mechanical relays not be used, as they would add a delay to the time, which was accurate to within 1/10 second.

This receiver was superheterodyne, with an IF of 465 kHz. The detector was regenerative, and could copy the CW signals, which were then simply rebroadcast over the air at the top of the hour.