> What is the power rating of R2? 30 mA through 2 k is 1.8 watts. > Likewise, what is the rating of R1?
Those are on the schematic sheet. R2 is your basic small resistor. What is that, 1/4W? R1 is a small 10-turn trim pot. Nothing notable about either one. > What if the MOV is intended only to clip transients and spikes? The > time That's all they're actually good for! I was just doing some worst-case math to see where it led me. > Note also that the R1 + R4 combination can vary 3:1 in resistance, a > rather wide range for adjustment. More than that, R1 is actually a 2k unit that was set at 1k. > I still wonder about Q6 and D11. If you're conducting through D11, Q6 > has > to be off. If Q6 is on, D11 cannot be conducting. In this case the > stored > energy in the red-green winding has to forward-bias the body diode of > Q6. That whole area is pretty mysterious. If Q6 were back-conducting, current would be limited by R9. There's another, beefier, back path through D11/D13. > BTW, do Q1 and Q2 have any heat sinking? I certainly hope so, > particularly > if they're run in the linear region. They're yoked together with a little piece of aluminum bent in a U. Not much area at all, a couple of square inches tops. -- Jim _______________________________________ http://www.okiebenz.com For new parts see official list sponsor: http://www.buymbparts.com/ For used parts email [EMAIL PROTECTED] To Unsubscribe or change delivery options go to: http://okiebenz.com/mailman/listinfo/mercedes_okiebenz.com
