[ARC5] FETs and ---odes

[Kenneth G. Gordon]

On 6 Aug 2011 at 12:58, Dennis Monticelli wrote:

> FYI.  A JFET is not a triode  It does have a "triode" like region
> prior to pinchoff, but beyond that Vds bias point the current
> saturates like a pentode.

Hello, Dennis:

Yes. It may ACT like a pentode, but it still has only three 
leads....like a tri-----ode...so, when replacing a multigrid-tube 
with one, which lead goes where?

Or does one have to use more than one FET to equivalate (a new word?) 
a tetr-ode or a pent-ode?

IMHO, in circuits which originally have tetrodes or pentodes, the 
circuit would have to be redesigned.

It should be reasonably obvious where to connect which lead if one 
were using an FET to replace a tri-----ode.

Voltages, of course, would be a different matter.

Ken W7EKB