History of the 11m HAM band

  We know the 11m or the 27MHz (27-Mc) band as CB (Citizens Band) band. Some people refer to it as the "chicken" band. CB radio was very populair before everyone had a mobile phone and internet. When you search for the 11m band history you will read numerous sites about how 11m CB started in 1958 with highlights in the seventies of last century including movies like "Smokey and the Bandit", "Convoy" and "Handle with care". But not many know that the 11m was a legal HAM band at least in north/south America, Australia, New Zealand, South Africa and south-west Africa from 1947-1958. 

Following several publications first experimental license was given to W6XBC (eXperimental BroadCast) in 1933, the experimental frequency was 27,1 MHz. Actually 27 MHz was considered VHF at that time. Transmissions took place from Yuma, AZ. The aim was to see if VHF was useful for remote broadcast pickups. They transmitted 1 hour per week and asked for reports. At around the same time the same frequency was used by a ship that was on arctic expedition. They used several callsigns, one of them was W10XDA.

Searching for more historical research I found that first commercial licenses were given in March 1928 to 6XAR in San Fransisco CA transmitting on 27,523 MHz, 2XBM in Water Mill NY transmitting on 27,900 MHz and 6XJ in San Diego CA transmitting on 27,900 MHz.

In the WW2 years 27MHz communication gear was used in tanks both by Germans and American armed forces. A story that can be read in several old CB magazines is about discovering 27MHz signals heard from German tanks stationed in Africa. Fiction or real, a HAM from Rhode Island recorded some strange voices he heard on the 11m band. One day he played the recording to a friend who understood German. This friend realized it was some military communication between tanks and base stations. When the US Navy was called in they found out it were tanks from general Rommel in North-Africa. Although the signals came in almost everyday it seems best to receive was at a few square miles in the Rhode Island territory. Intelligence immidiatly took over an old farmhouse at the sweet spot en installed a few 11m receivers and German translators. Every information that was transmitted in North-Africa by the German tanks and base stations was monitored and given to the British. After the war the 27MHz was no longer in use in the military but it certainly proves that this frequency did do well in difficult circumstances.

  Other users of 27MHz were doctors that used this frequency for medical uses like diathermy. This, of course, was a huge source of QRM and so the 11m was not really a populair HAM band. In 1947 the FCC allows use of the 11 meter band on a shared basis with Industrial, Scientific and Medical devices. Most HAMs operate on 11m with their 10m antenna, not really effective. In 1948 Firestone Tire Company granted experimental license W10XXD for 27.255 MHz (Ch 23) using two 3Watt transmitters. All documentation about this experiment is lost but these might be forerunners of CB radios as we know it now. 

Did you know that the US radio technical planning board proposed to lower the 10m amateur band by 1 MHz to 27-29 MHz. Although this proposal was later withdrawn, the ISM band (27,185 - 27,455 MHz) was not established until 1945, and the FCC hinted that it could be distributed to amateurs as a secondary service.

The 11m HAM band has been changed several times:

27.185-27.455MHz (March 26, 1946 to April 29, 1947) FCC Order 130-D (March 13, 1946), Federal Register Notification (11FR3158, March 26, 1946)

27.160-27.430MHz (April 30, 1947 to June 30, 1949): FCC Order 130-M (April 10, 1947), Federal Register Notice (12FR2815, April 30, 1947)

26.960-27.230 MHz (from 1 July 1949 to 10 September 1958)

The 11m HAM band was not only established in the USA. It seems 11m was also allowed in the America's (Canada, central/south America), South Africa, Southwest Africa, Australia and New Zealand.  International DX contacts were certainly possible.

But what did the HAMs do on 11m? Did they use it for nearby contacting or did they do make some DX? I searched in some old magazines to find evidence and found some remarkable things. Activity without the need for a experimental license was from 1947-1958.

-  1947 - The mountaineer amateur radio association operated W8BOK/8 at fieldday with 6 stations simultaneously. One of the stations operated "27-Mc phone".

- W3CDQ is planning a 27-Mc. 'phone-cw rig' for a net composed of amateurs connected with the Central Radio Propagation Lab. (CRPL) ionosphere group.

- Several amateurradio stations researched meteorscatter on 27-Mc

- 1948 - QST June 1948 reports W9AND,  worked EL5A, OX3GE, VO4T, KH6GT, KII6BI and CXlFB. W6ZZ reports working J9AAI. All on 27-Mc.

- 1950 - The 16th ARRL International competition also counts (DX) contacts on 27-Mc.

- 1957 - The FCC announces the end of the 11m HAM band to use it for "Citizens Band"

"Save 11 meter" contests were hurriedly organized among the Hams to show the FCC that 

there really was life in the old 11 meter band. About 400 stations rose to the occasion, and 

many exotic calls were to be heard, such as CX2AY, CN8JW, XE1A, ZP5IB, VK2QL, and 

KC4AI. Unfortunately these "protests" are not enough and didn't help to convince the FCC. 

The 11m HAM band came to an end. September 11 1958 was the date that 11m would be known as "Citizens Band". In fact Al Gross W8PAL is by most seen as the man that invented CB, although the idea was already brought up in 1938 by Herbert Brooks W9SDG. His letter to the editor of QST magazine described a theoretical "Citizens Band" nearly identical to what we know today. Al Gross actually developed equipment for the UHF band since CB on an experimental basis at that time was on 250MHz and later between 460-470MHz. It looks like he had the first official CB license issued in 1948. But W2XQD was really the first one with a CB license issued February 14, 1947. It would actually take another decade before CB started on the 11m band. 

Related reading links and documentation:

Detailed information about the schooner Morrissey arctic expedition radio experiment:

https://www.rsp-italy.it/Electronics/Magazines/QST/_contents/QST%201934_12.pdf

History of the 11m band documentation:

https://ukspec.tripod.com/rf/cb/

https://www.retrocom.com/wtcollect/27_megacycle_history_in_the_u.htm

https://sites.google.com/site/cb465mhz/home

Another article I wrote about Al Gross:

https://pe4bas.blogspot.com/2014/11/historical-first-time-1944-handheld.html