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MicroBlocks Guru Joined: 12/05/2012 Location: ThailandPosts: 2209
Posted: 11:13pm 12 Aug 2013
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I suspected something like that.
I like the colors the maximites have. Good and bright. Staying with the 4148 seems the right thing to do, otherwise it would need experimenting with resistor values. And who knows maybe in the future there will be a modification. It would be best if the circuit is the same.
Microblocks. Build with logic.
robert.rozee Guru Joined: 31/12/2012 Location: New ZealandPosts: 2401
Posted: 12:06am 13 Aug 2013
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hadn't considered the voltage drop - you are right that a schottky diode will have a much lower forward drop and so be no good for clipping the video levels.
at a pinch you could use three BC847 transistors, each with base-collector shorted. this will provide you with the required 0.6v clipping level, and the BC847 comes in a sot23 package. 7 cents each in quantities of 250 from RS, us$2.30 for 100 with free shipping on ebay.