THE WAYBACK MACHINE
by Bill Continelli, W2XOY
reprinted with permission
In our last installment, we saw how the FCC shifted from an initial VHF/UHF bandplan that was radically different from today's allocations, to a proposal which closely parallels the frequencies we have today. Amateurs were happier with the January 1945 plan over the November 1944 one, as it restored our ten meter band back where it belonged, and gave us a full 4 Mc at six meters.
One person who was not happy with the January 1945 plan was Edwin Armstrong, inventor of the Regenerative, Superregenerative and Superheterodyne receivers, and the Father of FM. He wanted the FM Broadcast band to stay in the 42-50 Mc area: instead, he suddenly saw it transferred up to 84-102 Mc., which would make every FM station and receiver obsolete. He knew that David Sarnoff of RCA was behind this, as RCA wanted television in the frequencies now occupied by FM. Sarnoff and the RCA engineers had an interesting argument, FM they said, should be moved higher in frequency to avoid the Sporadic E skip.
Armstrong fought back. He pointed out that FM, due to it's capture effect, was less susceptible to skip interference than television, which used AM for the video carrier. He ran tests and submitted data showing that the skip interference to FM would be far less than imagined, and certainly a fraction of what TV would endure. The ARRL, by the way, was in favor of moving FM up to the 84-102 Mc area. To counteract the arguments that FM receivers would become obsolete by the move, QST in the May 1945 issue ran the schematic of a 1 tube converter, which Hallicrafters said they could build for $5.60.
In late May, 1945, the FCC announced the three alternatives that were being considered for the disputed 44-108 Mc region. They were:
ALTERNATIVE #1 --
44-48 Mc--Amateur (We would have a 7 meter band under this proposal)
48-50 Mc--Facsimile Broadcasting
50-54 Mc--Educational FM Broadcasting
54-68 Mc--Commercial FM Broadcasting
68-74 Mc--TV Channel 1
74-78 Mc--Aeronautical fixed and mobile
78-108 Mc--TV Channels 2-6
ALTERNATIVE #2 --
44-56 Mc--TV Channels 1 & 2
56-60 Mc--Amateur 5 Meter Band
60-66 Mc--TV Channel 3
66-68 Mc--Facsimile Broadcasting
68-72 Mc--Educational FM Broadcasting
72-86 Mc--Commercial FM Broadcasting
86-104 Mc--TV Channels 4-6
104-108 Mc--Non-Government fixed and mobile.
ALTERNATIVE #3 --
44-50 Mc--TV Channel 1
50-54 Mc--Amateur 6 Meter band
54-84 Mc--TV Channels 2-6
84-88 Mc--Educational FM Broadcasting
88-102 Mc--Commercial FM Broadcasting
102-104 Mc--Facsimile Broadcasting
104-108 Mc--Non-Government fixed and mobile.
Except for the 44-108 Mc region, which was still up in the air, the 25-44 and 108 Mc and higher frequencies were fairly well established at today's allocations. The only major exception was the 470-480 Mc band, which was still allocated to Facsimile Broadcasting. The FCC indicated that tests would be run through the summer months to determine which Alternative was the best.
Reaction was quick to the proposals. Except for the ARRL, almost none of the major players liked Alternative 2, so the choice lay between 1 and 3. The ARRL found #2 acceptable because it preserved our 5 meter band. Of the other two alternatives, the ARRL was strongly opposed to #1. A 44-48 Mc seven meter band would have too much skip, was too close to our ten meter band, and too far from two meters. In the end, the ARRL came out in favor of Alternative #3 because, it was believed that the FM band should be as far as possible from our ham bands in order to avoid IF interference to FM receivers.
Naturally, Major Armstrong was in favor of Alternative #1. He continued to make extensive tests and bombarded the FCC with the results. However, Armstrong never realized that the political clout of General Sarnoff and RCA could overcome any test results. The Major thought he had the summer to complete his tests. Instead, on June 27, 1945, the FCC decided on Alternative #3, with a few minor changes to bring the allocations in line with what we have today. FM was definitely at 88-108 Mc, and amateurs had a six meter band at 50-54 Mc, nestled snug between TV Channels 1 and 2.
Armstrong was stunned, but he didn't give up. As late as 1947, he was still submitting data to the FCC in regards to the effect of skip on FM Broadcasts. But it was too late. For a period of time, there were two FM Broadcast bands, as stations in the new 88-108 Mc allocation coexisted with the older ones between 42-50 Mc, but by 1947, the old FM band was a memory, and sat waiting for TV Channel 1 to take over.
However, a new controversy was brewing. With thousands of amateurs on our new six meter band, and thousands of TV's pouring out of (mostly RCA) factories, a new concept was entering the amateur language -- TVI. In our next installment, we will look at the TV wars of the 1940's and why the ARRL wanted channel 2, instead of channel 1, eliminated.
So, until then, I hope your six meter QSOs aren't causing interference to the "Texaco Star Theatre."
All material Copyright © William Continelli
All Rights Reserved