811a coil/ bad diode?

["Tesla list" <tesla-at-pupman-dot-com>]

Original poster: "Steven Ward by way of Terry Fritz <twftesla-at-qwest-dot-net>" <srward16-at-hotmail-dot-com>

Hi group,

I think that i may have come across my problem with my small VTTC that ive 
been working at for awhile.  I decided to check out all of my components 
today and found that my diode is not testing good.  It reads open circuit in 
both directions.  Is this a sign of a bad diode?  I know that it would 
usually be, but are microwave diodes different?  Another diode (suspected 
bad as well) i have reads 4kohm im both directions.  I think i may have 
blown the diode when someone on this board told me that the schematic was 
incorrect.  I followed his directions, and blew a 15A fuse, and was probably 
quite close to blowing my tube! im sure that amount of power could destroy 
that little diode.  So i followed the original plans and the coil works OK 
giving about 3" sparks at most, with unopredictable performace from time to 
time. Ive been running the coil for a few days with out realising my diose 
may be bad.  This makes me suspect the diode.  So do i need a diode?  or can 
i bypass it?  a new diode isnt much of a problem but i want to know it i 
even need it, and if i dont what other modifications do i need to make?  
Thanks,

Steve Ward.