This TV talk has me thinkin'... I've seen the Pong & Tetris games. I've got a use for a pair of crosshairs on a screen. Nothing fancy, no moving graphics or anything like that--just a couple of lines--but I need them as thin as possible. What is the thinnest line I can expect to get? I know the Pong game has a resolution of somewhere around 50 (or is it 150?) but I'd like something as thin as maybe 1/400th of the screen, X&Y. Anybody know if that's possible? Got any links? Thanks, Cliff ----- Original Message ----- From: "Dave Dilatush" To: Sent: Thursday, January 17, 2002 3:04 PM Subject: Re: [EE]: TV Modulator with LM1889 This appnote can be downloaded from National's website, at: http://www.national.com/an/AN/AN-402.pdf HTH... Dave Vern Jones wrote... >See if you can find a National Linear Applications Handbook--1986, look >at AN-402. It discusses the LM1889 and LM2889 chips. The VSB Filter is a >Vestigial Sideband Filter and is a pre-packaged circuit cut to channel 3 >and 4. You have the channel 3 and 4 Video Carriers (AM) and the channel >3 & 4 Audio carriers (FM) 4.5 Mhz removed from the AM video carrier, and >then the Chroma signal at 3.58 Mhz these frequencies are closely linked >for a 6Mhz wide bandwidth for channel 3 or 4. The sound and Video >oscillators use lc components, the SAW (VSG) filter is premanufactured >you could probably design a LC band pass filter to limit the Vestigial >side band. A TV channel has a lopsided picture bandwidth. It is 4.5 Mhz >on the upper side band and 1.25 Mhz on the lower side band. The >vestigial filter cuts off the lower 3 Mhz of the lower side band tho >keep the video carrier from channel 3 from interfering with the audio >and video carriers of channel 2. > >I dont have the document in pdf form or would send it, maybe someone >else has it... -- http://www.piclist.com hint: PICList Posts must start with ONE topic: [PIC]:,[SX]:,[AVR]: ->uP ONLY! [EE]:,[OT]: ->Other [BUY]:,[AD]: ->Ads -- http://www.piclist.com hint: PICList Posts must start with ONE topic: [PIC]:,[SX]:,[AVR]: ->uP ONLY! [EE]:,[OT]: ->Other [BUY]:,[AD]: ->Ads