I need the update manager to only download a single package at a time and not try to download multiple packages at once.

My slow internet cannot handle multiple connections; slows the download to a crawl and some packages will reset themselves halfway through when they time-out.

EDIT

When using apt-get update multiple repositories get checked:


When using apt-get upgrade multiple packages are downloaded:



Question: Why was a resistor and capacitor used in this IR receiver circuit
Answer: The author of that diagram swapped the connections for output and power. Check the datasheet of the TSOP17 series and you will see that it has 3 connections, not 4, and the missing one is the one that is unconnected in your diagram.



The top connection (1) is the output (NOT +5V as in your diagram). It is open collector, but is has an internal 100k pull-up, so in most cases you won't need an external pull-up. 



Connection 3 is the +5V. The datasheet recommends to decouple it with a 330R / 4u7 filter. Your diagram shows 100R / 100u, which IME is OK too. Needless to say, this pin is NOT the output.