The house I moved into had a cat5 cable running from their video doorbell to their base unit instead of a "regular" 2 conductor wire (that I've seen in previous places).
I want to upgrade to a Nest doorbell and don't want to run new wire through the house so plan to use the same existing cat5 cable to do so. I've been advised to "double strand" the wires in the cable to ensure that it has enough power.
One issue I have is where the cable comes into the house, it is not long enough to reach the junction box where I plan to put the 16V transformer. This leads me to my 2 main questions:
To double strand, is it literally just twisting the copper ends of two wires within the cable together and hooking that into the screws?
Because the cat5 cable isn't long enough to reach the transformer, can I attach a similar gauge of wire (or more accurately, a gauge that matches two 24 or 26 gauge cat5 wires twisted together) with a wire nut to create an extension to reach the transformer?
Does the gauge of the wire from the transformer to the chime have to match that from the doorbell to the transformer?
Is there anything else I should know or am blatantly ignoring?
Here are some photos if it helps:
Current doorbell wiring outside: https://imgur.com/Rb7vmDX
Base unit (in kitchen): https://imgur.com/njvSTkS
Junction Box (in kitchen): https://imgur.com/DQcHxhl