Hello all,I need some help with reading the Com III schematic so I can get on the BUS!1) R1 is labeled as 2k2. Should it be 22K Ohms?2) R4 is labeled as 4k7. is it 47k Ohms instead?3) LED1 - what is "rot" ??? & is it conected directly to the ground pin of the 12V regulator???4) Over here, we don't have Nano Farad caps. I am assuming C7 is same as a .1uf cap (that is if I got my conversions right).Thanks for all the help. Best RegardsSean W

Hi Sean,>1) R1 is labeled as 2k2. Should it be 22K Ohms?>2) R4 is labeled as 4k7. is it 47k Ohms instead?A letter in between the numbers defines a decimal point, and the letter itseft a multiplier. k = Kilo = 1000 = 2.2 x 1000 = 2200 Ohms = 2.2KOhmsi.e. 2k2 = 2.2K Ohms, 4k7 = 4.7K Ohms, 1M2 = 1.2M Ohms etc...>4) Over here, we don't have Nano Farad caps. I am assuming C7>is same as a .1uf cap (that is if I got my conversions>right).'u' in capacitors stands for micro. Normally it's written with the small Greek letter m but since not all keyboards/fonts have it theydisplay it as 'u'. So uf = microfaradAnd I can't believe you don't have nF over there! They are most common!Regards,George DorkofikisAthens, Greece

Sean W I assume you are in America, if yes...Usually its hard to find nanofarad or picofarad caps at any local electronics store. The best thing is to order them through www.digikey.com nor www.jameco.com nor www.mouser.com. I assure that they have a lot of them in stock. A ceramic or polarize type.

Thank you both for your help. It's much appreciated.I still have a couple of questions....LED1 - what does "rot" means?. It's written near the LED on the schematic. Does the 12V regulator get it's ground thru this LED? And Finally, No luck finding Nano farad caps locally, but couldn't I use a .1 micro farad cap instead. (isn't 100nf =.1mf ?)Thanks Again.SW

Hi,"rot" means red - it is a red LED.If you have trouble getting the parts - you can order complete built FSBUS units or the sole partes and sole PCB

Sean W I dont want you to misunderstand about symbols-- there isn't any "m" symbols for capacitors. I assume you meant micro, and the symbol for micro is "u" with front "tail".Symbolsm = milliu = microp = picon = nanoAnd those symbols came from greek. Why? I wouldn't know. But most electronic engineering think it'd be best to use symbol instead writing down too many zero as value. For exampleif m = 1 u = .001 p = .000001 n = .000000001if m = 10 u = .01 p = .00001 n = .00000001Note: Move decimal at - 3 on every values...Hope that helps

I believe you have the pico and nano multipliers reversed. Nano is 10E-9 while pico is 10E-12. There are 1000 pico-farads in a nano-farad, 1000 nano-farads in a micro-farad.Just to make things more confusing, If you look at electronics from the 50's you'll see capacitors marked with "mfd" and "mmf". "mfd" should mean milli-farad but doesn't. It actually referred to micro-farad, perhaps because the printer did not have the proper greek letter. "mmf" referred to micro-micro-farad, what we today call a pico-farad (or sometimes a "puff").Mikewww.mikesflightdeck.com

Oh Mike, I can't believe it, I am still going through same problem since back day in college. A reversing between nano and pico, is the most target mistakes that I have always encounter. I remember, at the begin of learning on AC electronics. My AC instructor always emphasize me to remember, since Nano and Nine has same first letter therefore nano must equal to E-9 and and unbelieveable my memories just fades away just til you remind me again. Thank you for the correction. Hopefully, I can keep it in my head. :-LOL