[Lowfer] 8 kHz VLF loading coil idea

[lowfer@mailman.qth.net]

 trying to hear/see the tiny signal! :-)
> I think that the loading coil required at VLF is the most difficult 
> part of
> the whole system, especially making the coil easily tunable. My idea 
> is to
> make a tunable loading inductor by using a high voltage transformer, 
> such as
> a MOT (microwave oven transformer) or plate transformer, having a 
> bit more
> than the required inductance, and applying a variable DC bias to it 
>

MOT will work and are useful as HV transformers but you will need to
remove
an additional bit of the core which act to limit the current on a high
load. This 
should be spotted and tapped out wit a hammer N screwdriver. I was using
one fer HV
and after removing this the regulation much improved. 

so I would think you may want to do it for the use you are putting it to

your idea sounds worth playing with
keep the lost posted

Bob  K3DJC