Sounds like something out of Walt Maxwell's book:
Reflections
Transmission Lines and Antennas
This is a real good reference for any ham.
The first two chapters are titled:
1 - Too Low an SWR Can Kill You
2 - Countdown for a Journey from Mythology to Reality
Good reading...
Larry KA5T
Georgetown, TX
On Fri, 07 Jan 2000 13:31:13 -0600, Richard Matthews wrote:
>
>I don't know who wrote this, wasn't me, but I wonder how those on the list
>feel about it. I tend to agree, being one that has never worried a lot
>about SWR.
>
>WA4NWW, Richard
>
>
>SWR Myths ..... The Facts And Fiction
>
>
>"I don't know where all the feedline myths started, but I suspect it had
>something to do with the do-it-yourself swr bridges which first became
>popular back in the early 1950s. Until then, most amateurs didn't even know
>about standing waves and, if they did, they didn't seem to care. However,
>swr bridges soon caught on, and it wasn't too long before getting caught
>with your swr up was synonymous with getting caught with your pants down!
>Some hams dug into the books, but when they discovered that swr is caused by
>a mismatched antenna, it only served to reinforce the myth. If a mismatched
>antenna causes power to be reflected back down the line, they reasoned, this
>power obviously wasn't radiated by the antenna. Some even suggested that
>the refelcted power got back into the transmitter tank and was dissipated
>in heat. Others apparently thought that reflected power was lost forever
>tosome great swr heaven in the sky. A few well informed amateurs tried to
>nip these absurdities in the bud, but it was hopeless.....the disease spread
>faster than the cure. Transmission lines are too complex to be covered here,
>but let's bury the myths. First, reflected power is not lost nor does it
>heat up the tank circuit of your transmitter. Second, if the feedline has
>low loss, as is in the case on the HF bands, increased loss due to swr is
>so small that you can forget about it. Since a 10:1 swr on 100 feet of RG8U
>at 4 mHz increases loss by less than 1 db, don't worry about the fact that
>the swr rises about 2:1 at the band edges....the station at the other end
>won't be able to tell the difference. If your transmitter doesn't like to
>load into a mismatch greater than 2:1, buy or build yourself an antenna
>tuner and save yourself a lot of grief by forgetting the swr on the line
>to the antenna if it's within reasonable limits, say 10:1.
>
>
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