(ET) Diode Check my multi-meter checks voltage not resistance

[Allen Hunt <allenhunt_2000 yahoo com>]

Hi Everyone,

Thanks for all the previous help.  My new multi-meter
(Greenlee DM-100) reports volts when you check a
diode.  Doesn't seem to have an AC/DC selector for
diode checking.  One diode gives a reading of .476 and
the other is apparently bad.  The service manual says
that the resistance is supposed to be at least 100:1. 
How does resistance equate to the volts?  BTW, I am
looking for a replacement transformer.  (mine burnt to
a crsp)

Thanks 

Allen