{"id":2400,"date":"2016-10-17T13:50:17","date_gmt":"2016-10-17T21:50:17","guid":{"rendered":"http:\/\/pididu.com\/wordpress\/?p=2400"},"modified":"2016-10-17T13:53:18","modified_gmt":"2016-10-17T21:53:18","slug":"if-not-us-then-who","status":"publish","type":"post","link":"http:\/\/pididu.com\/wordpress\/blog\/if-not-us-then-who\/","title":{"rendered":"If Not Us, then Who?"},"content":{"rendered":"
\"ptc<\/a>
Solar bike power transfer controller board, configured as a function generator. There are already test points on the board, to which a scope probe can connect. The logic voltage regulator is bypassed, and just brought out to a USB connector. To provide a floating waveform, the whole thing is powered from a USB charger battery (cylinder near top left).<\/figcaption><\/figure>\n

“If not us, then who?”<\/em><\/p>\n

This is a tag line from one of my favorite movies, Machete<\/em>.<\/p>\n

Recently, I needed a function generator to help test some oscilloscope software I’m working on. \u00a0Unwilling to shell out for a formal piece of equipment, I decided to build one out of a PICAXE. \u00a0It could have been wired on a solderless breadboard, I suppose. \u00a0Or a perf board. \u00a0But then I realized that I had 4 more blank fabs of the solar bike power controller, already laid out for a PICAXE. \u00a0It seemed a waste to use basically a $20 board to wire up such a simple thing, especially since just the tiniest fraction of the board would actually be used.<\/p>\n

But then I thought, “If not for this, then what?”<\/em> \u00a0The extra proto boards were just lying around doing nothing, and I had already decided to make a major revision to the board. At my age, I find myself asking this question a lot – what am I saving it for?<\/p>\n

Here are some pictures of the waveforms captured by my software. It’s got a long way to go, but having a function generator handy will accelerate development greatly.<\/p>\n

\"5<\/a>
At a slow sweep rate, the waveform looks like this.<\/figcaption><\/figure>\n
\"5<\/a>
The waveform was designed to be useful at higher sweep rates, also. Each spike actually has a high-pass RC filter on it, to show features at this sweep rate, which is 1000 times faster than the previous picture.<\/figcaption><\/figure>\n","protected":false},"excerpt":{"rendered":"

“If not us, then who?” This is a tag line from one of my favorite movies, Machete. Recently, I needed a function generator to help test some oscilloscope software I’m working on. \u00a0Unwilling to shell out for a formal piece of equipment, I decided to build one out of a PICAXE. \u00a0It could have been … Continue reading If Not Us, then Who?<\/span> →<\/span><\/a><\/p>\n","protected":false},"author":1,"featured_media":0,"comment_status":"open","ping_status":"open","sticky":false,"template":"","format":"standard","meta":{"footnotes":""},"categories":[204],"tags":[212,64,56],"_links":{"self":[{"href":"http:\/\/pididu.com\/wordpress\/wp-json\/wp\/v2\/posts\/2400"}],"collection":[{"href":"http:\/\/pididu.com\/wordpress\/wp-json\/wp\/v2\/posts"}],"about":[{"href":"http:\/\/pididu.com\/wordpress\/wp-json\/wp\/v2\/types\/post"}],"author":[{"embeddable":true,"href":"http:\/\/pididu.com\/wordpress\/wp-json\/wp\/v2\/users\/1"}],"replies":[{"embeddable":true,"href":"http:\/\/pididu.com\/wordpress\/wp-json\/wp\/v2\/comments?post=2400"}],"version-history":[{"count":0,"href":"http:\/\/pididu.com\/wordpress\/wp-json\/wp\/v2\/posts\/2400\/revisions"}],"wp:attachment":[{"href":"http:\/\/pididu.com\/wordpress\/wp-json\/wp\/v2\/media?parent=2400"}],"wp:term":[{"taxonomy":"category","embeddable":true,"href":"http:\/\/pididu.com\/wordpress\/wp-json\/wp\/v2\/categories?post=2400"},{"taxonomy":"post_tag","embeddable":true,"href":"http:\/\/pididu.com\/wordpress\/wp-json\/wp\/v2\/tags?post=2400"}],"curies":[{"name":"wp","href":"https:\/\/api.w.org\/{rel}","templated":true}]}}