Sean,
bridge as a few different meanings.
So you have as wireless router with a SSID of MYNETWORK and you want to add your 1200 to extend coverage, correct? If so, you would need to connect your 1200 via wired to the router and then configure the 1200 with the identical security settings. Note, roaming may not be ideal. But for home use you should be ok.
http://www.cisco.com/en/US/products/hw/wireless/ps430/prod_configuration_examples_list.html
Look under autonomous basic config for some examples.
"Satisfaction does not come from knowing the solution, it comes from knowing why." - Rosalind Franklin
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