On Tuesday, February 10, 2015 10:01:13 AM Dean Posekany wrote: > On 2/10/2015 3:00 AM, Gene Heskett wrote: > > snip > > > The diode checker of the modern meter reads the voltage drop, fwd > > direction on this type of diode s/b under .15 volts, while the > > reverse of the probes should show a much higher voltage, maybe even > > off-scale for reverse. Right where they sit in circuit. A reading in > > both directions that is similar and probably under .1 volts is a > > shorted one. > > I checked the three diodes on the bottom near output port and they all > read generally the same: forward bias ~0.48V and reverse bias ~1.47V. > I checked a few of the topside diodes of the same value and got: > forward bias ~0.48V and reverse bias .OL. It appears that the bottom > diodes are bad. > > Is there any way to check the FET's.
I neglected to answer this question. My bad. Generally speaking, if they have a low reading from source leg to drian leg, at either polarity of the meter leads they are probably shot. If a OL is seen, determine which is source and clip the negative button of a good 9 volt battery to it, then apply the + terminal to the gate, and unless the circuit has a low enough ohmage to kill the battery, the FET should turn on and give a very low reading from source to drain. If that fails, I'd do the replacement. That is somewhat simplicated, but is a general rule. Cheers, Gene Heskett -- "There are four boxes to be used in defense of liberty: soap, ballot, jury, and ammo. Please use in that order." -Ed Howdershelt (Author) Genes Web page <http://geneslinuxbox.net:6309/gene> US V Castleman, SCOTUS, Mar 2014 is grounds for Impeaching SCOTUS ------------------------------------------------------------------------------ Dive into the World of Parallel Programming. The Go Parallel Website, sponsored by Intel and developed in partnership with Slashdot Media, is your hub for all things parallel software development, from weekly thought leadership blogs to news, videos, case studies, tutorials and more. Take a look and join the conversation now. http://goparallel.sourceforge.net/ _______________________________________________ Emc-users mailing list Emc-users@lists.sourceforge.net https://lists.sourceforge.net/lists/listinfo/emc-users
