KØHB wrote:

Jim,

Are you suggesting that Toshiba should employ non-professional amateur
engineers to build their TV's to avoid this problem?

Or are you suggesting that even professionally designed equipment may
sometimes fail and generate a "birdie" at 121.5 or 243.0?


Turns out that 121.5 is the 9th harmonic and 243 the 18th
harmonic of a commonly used digital TV sampling frequency
of 13.5MHz, used in DVD players. Some shielding inside
must have come apart in that TV. And the errant signal
travel up to an antenna or cable connection to leak out.
This has been a concern in the digital TV manufacturing
community.