Capacitor markings...?

[Bob Miller]

 Hi Joel,
    I'm afraid that you have been caught up in the ilk of various industry
comittees.  And when you combine that with a noble plan to standardize systems
of markings with the various capacitor types and manufacturing methods the
problem only gets worse.  The limited printing space on these rascals only
exascerbates the problem. Beyond value is the structure and makeup of the
capacitor in question which may also be encoded in the number.  The conventions
on capacitor marking are many and varied and further complicated by time (era
of manufacture).  Keep in mind that standards are quite neat, everyone has
one!  My suvival mechanism was the acquisition of an  Almost All Digital
Electronics L/C measurement device that not only measures the damn things but
keeps the magnitude markers in my generation of radio dudes, no nanofarads for
me. Pico I can deal with, but in reality I am a mmfd kind of fellow.

    73
        Bob, KE6F


Joel Govostes wrote:

> I'd appreciate some clarification on capacitor markings and values.
>
> I thought that, for instance, a marking like "102" would mean 10 x 10^2 pf,
> or 1000 pf.
>
> Now, yesterday I went to a local shop to pick up three capacitors I needed.
>
> One was 100pf, disk ceramic.  When I got home I looked at the marking, and
> it read "100".
>
> A second was also 100 pf, and read "100J".
>
> The other was a silver mica, supposed to be .0022 mf, and it read "222J".
>
> SO, this gets somewhat confusing.  Wouldn't a marking of "100" mean
> 10 x 10^0, = 10 pf?  And would the "222" mean 22 x 10^2 pf = .0022 mf?  I'm
> missing something on the convention here.
>
> Thanks!
> JG
>
> --- --- --- --- --- --- --- --- --- --- --- --- --- --
> To subscribe: listserv at listserv.tempe.gov
> and in body: subscribe BOATANCHORS yourfirstname yourlastname
> To unsubscribe:  listserv at listserv.tempe.gov
> and in body: signoff BOATANCHORS
> Archives for BOATANCHORS: http://www.tempe.gov/archives
> --- --- --- --- --- --- --- --- --- --- --- --- --- --

--- --- --- --- --- --- --- --- --- --- --- --- --- --
To subscribe: listserv at listserv.tempe.gov
and in body: subscribe BOATANCHORS yourfirstname yourlastname
To unsubscribe:  listserv at listserv.tempe.gov
and in body: signoff BOATANCHORS
Archives for BOATANCHORS: http://www.tempe.gov/archives
--- --- --- --- --- --- --- --- --- --- --- --- --- --