"Bob Bob" wrote in message
...
Hi Paul

Just for interest what is the S/N margin with most commercial satellite
systems and how "strong" is the sun relative to those levels? I would
assume the margin for an end use TV viewer would be less than this?

Cheers Bob VK2YQA

The Carrier-to-Noise ratio for analog TV was recommended to be 8db or better
for a noise-free picture (~50dB S/N after demodulation). With my 10-foot
dish, the peak of a solar outage would render the picture unrecognizable as
such for up to a minute. This means the sun had to be about 4 dB stronger,
since I recall 4 dB C/N was no picture at all. I hope this helps.

Sidelight: Analog degradation showed up as a type of video snow known as
"sparklies," usually in brightly colored areas. The beginning of a solar
outage would always be the appearance of sparklies.

I had the analog system for almost 20 years, so I was pretty conversant with
these periodic outages.

Digital, I don't know. I have a small dish setup but I haven't played with
it in years.

Sal