wifi repeater

OK, let me start off by explaining my current situation.
i live deep in the mountains in a valey. as you can see from the pic below, i get my wifi from a tower on the mountain. i dont need any boosters or antenas from my house, i can get good signal straight from my macbook internal wifi.
the tower has an omni that give a nice strong open signal to the valey. the open signal is not a problem for me because there are no other people for miles. just me. so for the moment all is fine

but i need to move deeper into the mountains to continue my work. this means there will be a mountain between me and the tower. i need to put some sort of repeater or range extender on the 2nd mountain to bounce my signal.

what hardware would i need to do this? i have a spare microtik RB411 and a R52 radio card. could this be configured to do the trick, or do i need a board that can take 2 radio cards?
any ideas how i can make this happen for the least amount of cash? i know, im cheap!

getting technical help out here is hard as i am out in the sticks, and the mountain is high to climb.

please share your thoughs

is that tower A in your control? if yes, does it run a MikroTik RouterOS device, or some other brand ?

Tower A consists of a RB433 running on routerOS, a 25db Grid dish pointing to nearby town, R52 radio and an omni that sends an open, (no password) signal to the valey.

all the hardware is mine, i installed the tower, however, it is not in my controll, as some one else configured the board and he is not around anymore. also, tower A is very hard to get to as the mountain is steap and high. because i am so far out in the sticks, been struggling to get my isp out here

is there a way i can just bounce the existing open signal over the second mountain without change to tower A?

at the moment tower A acts like an open hotspot.

the best option would be to add additional wireless card to the board and point an antenna to other tower. If it isn’t possible then you can try to use WDS link between the both towers to extend the range.

Here is similar configuration that might help you to understand how to configure that setup:
http://wiki.mikrotik.com/wiki/Wireless_WDS_Mesh
Look on the Model 2 setup configuration.