hello,
i am using scheduled tasks for enabling/disabling wlan. excample:

30 23 * * 0-6 uci set wireless.@wifi-device[0].disabled=1; uci commit wireless; wifi
0 5 * * 0-6 uci set wireless.@wifi-device[0].disabled=0; uci commit wireless; wifi

for a shortime a configured a second wlan (named "wlanForGuest"), and now i would like to upgrade my scheduled tasks. what is the correct name in the scheduled tasks?

wifi-device[1] ???

or

wifi-device['wlanForGuest'] ???

i am using tp-link 1043nd and OpenWrt Barrier Breaker 14.07 (+LUCI)

uci show wireless will show you which radios are which as well as using LUCI and choosing network -> wireless

Your script is switching on/off the whole wifi device, not a single interface... If you want to control interfaces, use "set wireless.@wifi-iface[x].disabled" instead; you can also use "set wireless.your_ssid_here.disabled".

Give your interfaces specific names in /etc/config/wireless:

config wifi-iface 'guest'
    option mode 'ap'
   etc

Then you can set wireless.guest.disabled=1, and always be referring to the guests' AP.

It would also be clearer to write small scripts and execute them from chron.