11 meter band In the 1950s

A curious history. Most information is found on forums. The band that would become Citizens Band began its current life in 1952 ish as an Amateur Radio band that was shared with mostly unregulated medical equipment that had primary access to the band. Diathermy (?) machines were the biggest source of interference but there were others.

I get conflicting reports that say the band was permitted or not, for novice Amateur Radio Licence holders. One report says the Novice licence at that time allowed 80 meters, 40 meters, and 11 meters. This would change through the early years.

Loss of the band for Amateurs was about 1959. Few Amateurs complained as the band was saturated by interference from medical devices still. Novices were moved to a segment of the 15 meter band, a much better band. 11 meters has always been referred to as the junkyard of the radio spectrum.

Non Amateur public access required a licence early on. There were several classes with licensees limited in power based upon their class of licence. Under Amateur use the band was limited to CW and AM modes. When Public access took over the band was limited to AM voice. (As far as I can find). In the 1970s licencing would be eliminated. The band would evolve into the class D licencing restrictions. 5 watt input power of AM modulated voice. With no licence required. You can find current law under Part 95 FCC regulations.

Under Amateur use in the 1950s remote control vehicle control was permitted with also CW and AM. The band was so poor because of local interference from Medical devices many Amateurs stayed away from the band. Equipment at that time was no where near the quality of Amateur gear today despite being state of the art at that time. More about equipment later.

The movies like Smokey and the Bandit among others are credited for fueling the public use of CB in the 1970s and 80s. In the UK CB was supposed to be regulated in use but very quickly got out of hand. Finally, the government there relaxed regulations. Before that many CB clubs, CB based pubs (bars), and many legal and illegal shops existed. Videos exist on the topic of UK CB on YouTube. FM operation legal in the UK, is very illegal in America, maybe even all of North America.

In the Early days Novice transmitters included 11 meters. Such as the Knight T50, Heathkit DX 40, Heathkit AT1, among others. I currently have 2. Novices were limited to 75 watts input to the antenna from the final amplifier. That is the equivalent of 50 watts output today. Many transmitters like the Knight T50 and Heathkit AT1 were built as CW only radios, with Crystal control to appease regulations regarding Novices.

Once a Amateur upgraded to a General Class licence he could alter his Novice Station by adding a VFO to one of the Crystal sockets, adding a Modulator to the key socket to inject AM voice onto the transmitted signal, and an Amplifier to the antenna socket before the Antenna for more power, if allowed on the band it was used on. A note here, many of these Radios had transformers that were considered inferior for AM use. They could cause a fire while in use.

A great many home made radios were designed for the same type of operation and modifications as allowed under the rules. Once CB operation became legal many manufacturers began to build and sell AM sets for public consumption. I have seen a very few with power tubes that suggest they were home modified back in the day for a lot more than 5 watts. It was easier to make modifications to a tube transceiver than a transistor model. Transistor sets became popularized in the 1960s.

Early on in the public access era, hand held transistorized radios became the rage. These radios were mostly governed by part 15 rules as most were 100 milliwatts output power. Few were more, eventually manufacturers began selling handhelds under 1 watt. About 999 milliwatts to keep under the part 15 regulations 1 watt limit. While giving a bit more range, these units still were at the mercy of propagation for decent range. 1-2 miles was average at 1 watt AM.

CW operation on 11 meters (or any band for that matter) is still permitted under part 15 regulations. Most kids type 100 milliwatt handhelds have a "telegraph key" built in for Modulated CW transmissions. This is allowed as part 15 operation in under 1 watt and different rules than part 95 that allows over 1 watt operation. Most part 15 operational range is measured in feet. Part 95 range is generally measured in miles. True CW or continuous wave operation is usually only encountered in the Amateur bands, military bands, and very few commercial/Maritime bands. CW would have much more range than MCW even at 100 milliwatts, depending on things like propagation, frequency range, operator skill, antenna, among other factors.

Handhelds have fallen from popularity in the past 2 decades. Decent range means 8 foot tall antennas with good grounds. Many handhelds today are little different than mobiles, being 5 watts. Often it is much cheaper to buy a cheap mobile for $20-$50 to get the same results as a $100 handheld. (You can find few handhelds online). Many 100 milliwatts handhelds today are little more than kids toys and do not perform as well as cheap FRS UHF radios. FRS is in some ways replacing some CB use with lower noise and less required skill. Even at 5 watts a CB will outperform an FRS Radio for general distance in most instances.

Well this has been a brief history. Much more exists online, but even that seems to hardly scratch the surface of the early days of the 11 meter band. I hope you enjoyed this brief examination. 73, Todd




Shared publiclyView activity