RCS North Zone Simulcast Site Location?

[KI6AOK]

I had the opportunity to visit the Lake San Marcos Peak RCS antennas recently. Here's a shot:

 

[K6CDO]

It's funny you should say that, Anderegg, because I seem to notice this a great deal on the analog talkgroups. For instance, listening to ALS Palomar I can have a nice clear signal on one frequency, but if the carrier drops and picks up on another freq, the signal will crackle and pop : ) I have not taken notice of which frequencies this happens on, but it looks like it might be worth it to pay attention next time and maybe keep track.

There are a number of factors involved in making a simulcast work. With 19 channels, each transmit site has two or three transmit antennas to handle the number of frequencies. These antennas are physically mounted as close together as practical so that the coverage is uniform, but there are differences in exact coverage. So the difference in channels at your receiver's location may be due to which antenna the transmitters at the sites serving that location are using.

The crackling is an analog artifact of the combined signals from multiple sites (just as the 'R2D2' effect is a digital artifact). In some cases, a moving vehicle near the receiver may be sufficient to cause an artifact, as signals will bounce off the vehicle.