> > Hello everybody...
> >
> > I hope somebody could solve my problem with regards to soldering and
> > desolderin a transistor. i'm currently workin on building a
> > s-parameter test board for measuring the s-parameters of transistor.
> > the plan is to hav a single board and make all students put their
> > transistors on the board, measure s-parameters and then take it off.
> > at first i thought solderin wud b good...but wats happening is while
> > desoldering atleast one of the pins is getting broken . and by the
> > time i melt the solder on all the 4 pads having 4 pins in order to
> > remove the transistor, they become cold and i'm not able to take the
> > transistor off...So i was wondering there shud b another way to do it.
> > if nebody could come up with a suggestion, it would b gr8. thanks
> > regards
> > chris
> >
> >
Its hard to find a reasonably priced socket to measure S parameters. Diamond
powder sockets work well, and are used in production, but would be overkill
and way to spendy for educational purposes. You might see if you can create
a stable pogo nest in some really high dieletric material. You should be
able to charaterise it, and then remove its influence. Even the HP fixtures
have to be calibrated prior to s-parameter measurement.
Ron