[Fwd: SV: LF: Signals and voices (138.9 kHz)]
Fri, 28 Aug 1998 18:11:07 -0400
Johan Bodin wrote:
> From: Johan Bodin, SM6LKM
> Dear all,
> I have reason to believe that the voice sidebands heard around the
> 138.9 kHz carrier actually *are* caused by the "Luxembourg effect".
> I have noticed voice sideband splatter in the 136 kHz band before,
> but I never gave it much thought until this subject came up on the
> LF reflector. Tonight I tuned to zero beat on the 138.9 kHz carrier,
> and to my big surprise, I heard Radio Sweden!!! (100% sure, their
> interval signal melody cannot be mistaken).
> The medium wave transmitter in Sölvesborg is transmitting on
> 1179 kHz with 600 kW. There are many other medium wave
> signals that are stronger than Radio Sweden at the moment, but
> Radio Sweden is actually what I hear on 138.9 kHz! Could it have
> something to do with direction? Seen from my QTH, the Radio
> Sweden tx is approximately in the same direction as the German
> 138.9 kHz tx.
> If a strong AM tx is able to "modulate" the reflection properties of
> the ionosphere in the vicinity, it explains why listeners in different
> locations hear different "ghost voices" on the 138 kHz carrier. The
> carrier is probably beeing modulated when its nighttime skywave
> "bounces" in the sky above the AM tx.
> Any thoughts?
> 73 de Johan