Can only get av1 and av2 when trying to tune lg v271 video recoder

yellow, white and red wires usually connected to the same name same colors on both devices.
Does the tv need to be on a certain channel? YES, try change to all ex: VIDEO 1, VIDEO 2, DIGITAL, ANALOG, HDMI or any according to tv sysem

no, it will not change your tv settings. because your only tuning the stations of your lgv271. so don't hesitate on tuning your lg v271.
if you have any questions, just ask me.

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As long as the N64 uses a composite cable (red and white for audio, yellow for video), you can use either connection.

AV1 connections are on the back
AV2 connections are on the side

Manual link:
http://www.lg.com/us/support/product/support-product-profile.jsp?customerModelCode=42LC2D&matchedModelCode=NOT_MATCHED&searchEngineModelCode=42LC2D&targetPage=support-product-profile&initialTab=documents#

I expect if you look at the menu you will find that AV2 is set up as S-Video or Component etc. etc. Set it up as composite or RGB. The same as AV1.

you should find them by seeing if you can find ports that are colored yellow, red and white

The Red, White & Yellow connectors are your composite inputs usually classed as AV3 or component. The AV1 input is a Scart connection, if you have a scart cable, connect this as your AV source & the TV will switch from AV to component.

I have a LG tv set. When i press the tv/av button on the remote my tv shows av1, av2 earlier but now it is showing only av. So i am unable to watch my dvd player. Need help.

Tried all combinations of scart connections and channel settings ,without result.Finally connected an external freeview box to VCR AV2,with through aerial feed to TV.Setting TV toEXT-1 and VCR to AV2 and with scart to phono adaptors connected box audio and video "out "with phono leads to audio video "in" using an adaptor into the TV scart socket.

To be able to select AV1, you have to first go into the setup menu and set the control set top box setting to OFF. I think you go to the menu >> setup >> features >> set top box control >> select OFF. Note that this has the side effect of erasing any previously stored timer settings.