How do i get a pictue on my samsung tv?

Sometimes on Samsung tv remotes there are input buttons up the top (tv, video, etc. These allow you to control other devices they ARE NOT hdmi inputs like AV1 AV2 etc) ensure that TV Button is pressed immediately before power. It is easy to knock the buttons and choose an incorrect input. Failing this pull out and reinsert HDMI/rca. failing this 1. power cycle the device. If this doesn't work contact retailer/Samsung.

Using the remote press either "input" repeatedly until you see what you'd like on the screen, or press TV/sat.

A customer changed the TV to AV1, I cannot get it back to
TV.

first of all, is it on the correct av channel, plugged into av1 and av1 selected on the tv.
is the lead good, can you swap around some leads with other known to be good leads.
are the leads pushed in fully, a scart lead can sometimes look like its pushed in fully when its not.
check for bent pins on each end of the leads.

Had to reset the TV and re-tune all channels. But it worked.

There should be a button on your TV remote that will be called "Display" or "P in P".
The display button usually displays which input you have selected, such as: SAT for Satellite; AV1, AV2, AV3 or AV4 - depending on how many inputs your TV has, to plug in devices like a VCR or DVD recorder/player.
Otherwise, if you have a more sophisticated TV, it could be that you have accidentally pressed the "P in P" button, that selects the Picture in Picture mode. If you have done this, your TV will display the main picture of the input you have selected, plus another input, (such as SAT or AV1 or AV2 etc. as I've mentioned above). If the AV1 or AV2, etc. input is not active (not switched on) then that input will only display a blank (black) picture in the top left corner of the screen.
Hope this helps...

u can up grade ur ariel,use manal instal, or get freeview,freesat or sky

if you have a cable box then it is probably the resolution settings in the cable box, what type of cable box do you have

try changing scart cable

may not be the inverter but the main board bad
nesco