That last pic shows, very nicely, the component I couldn't ID. It's an inductor (or "choke" in this configuration).
I'll work on the schematic this evening.
Thanks
Right, work done for the day, food eaten, cuppa on side
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I cheated & asked dad what that was earlier, he said it trims power, what does that mean
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& while asking found out 221 was a capactor, so after looking up, 221 is a cement plate capacitor that somehow compensates tempreture changes in tuned circuits but don't understand how at the moment but thats likely because they have values of pF that I haven't come across yet, see your meant to be impressed, I'm getting the bug of wanting to know how to identify parts now
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here we go, being clever I looked up 'chokes' thinking I was going to understand what that did
**broken link removed** the one I found looked like a resistor, so now your going to tell me all those resistor looking thingys on that mini pcb aren't all resistors aren't you
**broken link removed** ok, tried again, a choke is to slow down current in a magnetic field/ maybe ferrite core that alters frequency, have I understood that right
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Then theres long black & silver thingys, I take it the small gold one is a zener diode, but unlike normal diodes, allows current back the other way, value dependant
Will get back on phone now but carry on answering long questions tomorrow, including KISS's
This is more fun, love learning new things
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feel free to explain resistor looking thingys
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componant ID is a start
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Not at work until 12 tomorrow, so catch up bigger things then & continue with this post but feel free to carry on, didn't get any further with my understanding of scematic as I don't know some of the diagrams for stuff, but once I know what they are I can look them up
& have you heard of 'circuit wizard' is it any good?
yes, I'm well & truly hooked now
KeepItSimpleStupid; said:
Now the LED's have a Vf (min) an Vr(typ) and a Vr (max); What's worst case?
If can have some typical numbers and some max numbers and even some max numbers with pulse width attached to it.
Your resistors have tolerances; 10%, 5%, 1%, 0.1% With each tolerance group there is a higher cost and a "different set" of values. There are different types of resistors such as carbon, film and metal oxide.
There are resistors with low inductance.
In your design, they pretty much have no impact. Just because you ignored something here, doesn't mean it always gets ignored.
Nice datasheet on the surge stopper BTW. At the very least, I would invest in a TVS diode (18 V or so) and a Reversed biased diode in your design for the 12V power in, after the fuse. The reversed diode will attempt to clamp negative spikes and the TVS will help clamp positive ones.
Surely worse case for resistors is going past max load, which would blow the led light rather than it just not working with to lower a current or at very least it would just be dim
I had seen there were different tolerances, but thinking about it, the larger the tolerance, the more scope you have. Had also seen carbon film & metal resistors, I just thought carbon film ones were an older version? TBC.
