RCA output not working - Raspberry Pi Forums

just go pi. after setting sd card use debian, i've connected tv. works fine hdmi cable, when try connect through rca cable won't work. aware use rca, should disconnect hdmi cable that's not problem. also, i've set video mode "sdtv_mode=3" since live in brazil. ideas might problem?

here's config.txt in case may help:

# uncomment if no picture on hdmi default "safe" mode
#hdmi_safe=1

# uncomment if display has black border of unused pixels visible
# , display can output without overscan
#disable_overscan=1

# uncomment following adjust overscan. use positive numbers if console
# goes off screen, , negative if there border
#overscan_left=16
#overscan_right=16
#overscan_top=16
#overscan_bottom=16

# uncomment force console size. default display's size minus
# overscan.
#framebuffer_width=1280
#framebuffer_height=720

# uncomment if hdmi display not detected , composite being output
#hdmi_force_hotplug=1

# uncomment force specific hdmi mode (this force vga)
#hdmi_group=1
#hdmi_mode=1

# uncomment force hdmi mode rather dvi. can make audio work in
# dmt (computer monitor) modes
#hdmi_drive=2

# uncomment increase signal hdmi, if have interference, blanking, or
# no display
#config_hdmi_boost=4

# uncomment composite pal
sdtv_mode=3

#uncomment overclock arm. 700 mhz default.
#arm_freq=800

# more options see http://elinux.org/rpi_config.txt

apologies in advance if of these make "does think i'm stupid".
1. hdmi lead must removed before booting rpi.
2. composite video out (rca phono jack) baseband video signal needs connected baseband video input on tv - typically yellow rca phono jack. not work if fed aerial/antenna socket of tv.
3. sure switching tv composite video input? have other video source can plug in there check selecting correct input , input not faulty?
4. sure cable using not faulty?
5. i've no reason believe "sdtv_mode=3" doesn't work, in case, test, try "sdtv_mode=0". produces ntsc 525/60. tv should work albeit perhaps no colour.

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