Schematic Notation Help

[Yama Onan]

Hello all, I have a question regarding an OLD schematic. There is a capacitor value of 100 uuF.

Now, is that micro-micro Farad or is it actually, milli (m) ?

Thanks,

Yama

[Albert Kreuzer]

Hi Yama,

it's micro-micro-Farad, the same as today's picofarad.

HTH
Albert

[Yama Onan]

Thanks Albert!

I figured, since the whole IEEE standards industry probably wasn't as 'standard' back in 1960 (schematic era) as it is today.

Thanks again for backing my logic up. This board is priceless.

[Enzo]

Back in the 1950s, which was when I learned, we were taught terms like pico and nano, but they were not used. micro-microfarads - uuf - mmf, were indeed just todays picofarad. A lot of hams would refer to that as "mickey mouse", as in "I slapped a 47 mickey mouse cap across my dipole to..." Older times we used m instead of u. So .047mf instead of .047uf, and 47mmf instead of 47uuf.

Eventually uuf took over from mmf. I think largely because m meant milli on other places. And while milli-millifarad didn't make a lot of sense, a millifarad was possible. The very idea of a cap being 1 whole farad was just crazy back then. Now of course they install them in car stereos.

Nanofarads seems to me to be a fairly recent thing. I started seeing nano a while back and it is here to stay I guess, though I think I still see .001uf or 1000pf more often than 1nf.

[Enzo]

Oh and welcome to the board Yama and Hi from Lansing