We moved to a rural area and had very limited reception. I installed a Network extender but had only minimal improvement. Verizon sent a second extender (same model as the first). Can I install as a series? If so, how? Will it really help reception?
Did Verizon send you a 2nd extender as an additional device or to replace the current one? Its more common to receive a replacement device than a 2nd network extender from VZW. They may be expecting you to mail back the original as they have determined that it is not working properly.
>Can I install as a series? If so, how?
Yes you can install multiple network extenders on the same network. The process would be identical to connecting multiple Access Points in your home to a single Home Router. The additional network extenders would have to be connected to your home router via Ethernet cable and separated across your home so that they do not interfere with each other.
The topography would look like this:
=== ISP === Modem === Home Router === NE1
=== ISP === Modem === Home Router === NE2
=== ISP === Modem === Home Router ))) PC1
It is generally advised that you connect the NE direct to your cable modem instead of behind the home router to ensure it receives the full power of your internet connection. However if you are intending to use multiple NEs in the same environment then it should be acceptable to place it behind the home router instead and use normal home networking design principles to place them.
> Will it really help reception?
Depends on what the problem was with the first NE. Adding more NEs will increase the theoretical reception and coverage area, it will not necessarily improve the results that you have observed. There might be a bigger problem going on with the internet connection that you would have to troubleshoot first.