Hi list! I have a question. I need a variable-frequency square-wave timing signal in the range 3-5MHz. For slower applications, I usually wire up a 555 in astable mode with a pot to control the period (and maybe another to control the duty cycle, if need be). But I can't seem to get the 555 to go fast enough for my current project. I've been using a 4MHz crystal oscillator, but now discover I need to vary the frequency +/- 1MHz (with 50% duty cycle or so: it isn't critical). It would be great to be able to vary the frequency continuously with a pot. Any suggestions? Thanks in advance! Michael V Thank you for reading my little posting. _________________________________________________________________ Join the world s largest e-mail service with MSN Hotmail. http://www.hotmail.com -- http://www.piclist.com#nomail Going offline? Don't AutoReply us! email listserv@mitvma.mit.edu with SET PICList DIGEST in the body