"Highland Ham" bravely wrote to "All" (11 Jan 06 09:47:40)
--- on the heady topic of " 1N4007 varactors"

HH From: Highland Ham
HH Xref: core-easynews rec.radio.amateur.homebrew:90890

HH Zener diodes are often used as wide band 'noise generators'for use in
HH an impedance bridge used in conjunction with a receiver.

I understand to generate the noise that the zener diodes are operated
within their normal breakdown current range. However, as a varactor it
isn't desirable to have a breakdown current flow. The only tiny
current that flows is a saturation current which is related to
setting up the P-N junction boundaries within the semiconductor.

M*i*k*e