Total posts : 45366
i hope my last post wasn’t problematic. my ultimate goal is part 15 radio but i am trying to do as many experiments as i can to learn about this technology.
right now i’m trying to understand how you measure modulation on an oscilloscope. you mentioned in another thread ( http://www.part15.us/index.php?q=node/571 ) that you use “trapezoidal display” using an oscilloscope that has x and y inputs. my scope has x and y inputs but i am having a hard time figuring out how to use them properly. theres not much information online.
this website ” http://www.tpub.com/neets/book21/90a.htm ” is the best explanation i have found but even it doesn’t give me a very clear understanding. i have my antenna output hooked up to the y input and R33 hooked to the X input. is that correct?
this gives me two wave forms on my scope. i found a ‘horizontal mode’ setting i can change to ‘XY’ but that just gives me a weird blurred shape in the lower right of my display. here is a junky image of what i am describing: http://i.imgur.com/48yiM.jpg
any explanation would be appreciated.