How I Know I'm Old

An FB friend was commenting about something on the telly showing people how to tape music off the radio. I mentioned that I remembered trying to do that by holding the microphone of a reel-to-reel tape recorder next to the stereo speakers. (I have probably already lost any under 30's reading.) I would get all the way to the end of a song and the bloody dog would start barking.
How old does this make me feel? It pre-dates the smaller cassette tapes!
Then I started thinking about all the other things that, in my kids' eyes, date me back to the Pleistocene age:
Slide Rules - For some reason, we weren't allowed to use computers in our O Level maths curriculum, so slide rule it was.  I can't even remember what we did with it, let alone explain it to anyone. 
Car phones - Not that I ever had one myself, but I do remember a few other people having them in the 80's. This was obviously before cell/mobile phones were even thought of, and it's rather funny now considering that there is almost a worldwide ban on using a phone while you're driving. 
I also remember -
- having to get up to turn the TV to a different channel
- only having four TV channels (remember, this was the UK, Americans)
- not having TV in the middle of the day (ditto)
- getting breakfast TV in the early 80's (ditto)
- when VCRs came in
Creak. Must go and have my afternoon nap now.