The one way that degrade is appropriate is uncorrected bit errors occurring in one link will be propagated to the next.

... The only flaw is you assumed only one link will will be down at a time, if outages were random, the difference would be insignificant, but there is a good chance the outage is weather related, and more than one link will likely suffer from the same weather conditions.
You are correct about simultaneous link failures changing the overall reliability of the system. I decided not to deal with it in my "simplified example of transmission system reliability."

The one way that degrade is appropriate is uncorrected bit errors occurring in one link will be propagated to the next.
Under normal path conditions, the forward error correction in the ATSC standard should permit the receiver to detect and correct errors. Degradation should only occur when the path is operating near threshold conditions.

^^^Agreed (that is why I said uncorrected), but considering the link is going down due to bad weather, they are likely operating near threshold conditions at least some of the time.

Is CICO on the air? My box is waiting, but it has 98% signal.

^^^ Which transmitter? Toronto seems fine...

I get it out of Windsor. Most of the time is SD. Is it HD tonight?

OK I've got it here in SD again.

TVO Windsor has been back at 480i SD for at least 2 days now. :confused:

Not so sure about that. I tuned it early this morning/late last night and I saw an HD picture at the time...

Still at SD as of 8am this morning! One of the dominos must be down!

It seems to me that the process that knocks the signal down to SD is automatic...whereas getting things back to HD appears to require human intervention.

We've had snow squalls in southwestern Ontario today...it wouldn't surprise me if they're the culprit.

Still SD in Windsor....4 days and counting. Who's got HD or SD on the chain from Toronto???

Chatham is SD and has been for about a week now

You guys are contacting TVO with your concerns, right? ;)

http://ww3.tvo.org/contact

Yes, I called them last week, left a message. They called me back three times and unfortunately I was unavailable. I will try again this week.

I'm sure this has already been confirmed: But just to clarify, you're seeing 480i SD 4:3 being sent as the native channel resolution, and simply not standard definition 4:3 programming, right?!

Who's got HD or SD on the chain from Toronto???

Toronto and Paris (Kitchener) are both HD.

I'm sure this has already been confirmed: But just to clarify, you're seeing 480i SD 4:3 being sent as the native channel resolution, and simply not standard definition 4:3 programming, right?!
My DTV tuner tells me if I'm receiving SD or HD. Right now TVO from Windsor is SD. If the HD signal is working, the tuner tells me it's HD, even if the program is 4:3 SD.

^^^^^^^^^
Cool. I figured as much...just confirming...
TVO definitely needs to improve their delivery method for Chatham and Windsor.

I get both Kitchener 28.1 and London 18.1 for TVO at my location, London is SD as well at 480i and no PSIP the last time I checked. So looks like London, Chatham and Windsor are affected.