RSI La 1

{{Use dmy dates|date=October 2017}}

{{Use British English|date=October 2017}}

{{Infobox television channel

| name = RSI LA 1

| logo_size =

| logo = RSI La 1 2012.svg

| logo_alt =

| launch_date = 18 November 1958

| picture_format = 720p HDTV
(downscaled to 576i for the SD feed)

| owner = Radiotelevisione Svizzera di lingua Italiana

| country = Switzerland

| language = Italian

| former_names = TSI (1958–1997)
TSI 1 (1997–2009)

| website = {{URL|http://la1.rsi.ch/}}

| sister_channels = RSI La 2

| terr_serv_1 = Digital

| terr_chan_1 = {{strikethrough|DVB-T}}
(ceased on 3 June 2019)

}}

RSI LA 1 (la uno, formerly TSI 1) is one of two television channels produced by Radiotelevisione Svizzera di lingua Italiana for the Italian-speaking community of Switzerland. LA 1, which can be received in all parts of the country, is a generalist channel with a schedule encompassing news, entertainment, drama, cinema films, documentaries, and sport.

From 1993 to 1997 the British graphic design company Lambie-Nairn produced for LA 1 the idents and the commercial bumpers of the masked troubadour, who was played by the British actor Joplin Sibtain.{{Cite book |last=Lambie-Nairn |first=Martin |title=Brand Identity for Television: With Knobs On |publisher=Phaidon |year=1997 |isbn=9780714834474 |pages=194–205}}{{Cite news |date=January 1994 |title=Lambie-Nairn + Company reveal their role in helping the Swiss take on a new character |work=Creative Review |pages=44–45 |volume=14 |issue=1}}{{Cite web |title=Giù la maschera |trans-title=Take off the mask |url=https://epaper.cooperazione.ch/_deploy/CO/19931007/CO70/pdf_noenc/47_d44d93011f.pdf |language=it}}

As well as being transmitted digitally throughout the Confederation, LA 1's programmes are also receivable on cable and encoded, via satellite. Until February 28, 2009, the station was called TSI 1, and before that (before TSI 2 went on air) RTSI. RSI LA1 has also been broadcast in HD since February 29, 2012.