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Chokes/Transformers



Hi it's Tab,
I dont know if you remember but I asked a couple of questions about chokes
before. Thanks for the replies guys. The replies said that chokes are inductors
that are more resistive to high frequencies and voltage. Bearing in mind that
resonant frequency is calculated using inductance and capacitance - 
What I want to know is, (since inductors are coils and coils have capacitance
and inductance) will the extra inductance and capacitance affect the
calculations of the resonant frequency? will I have to take this into account
when making my calculations?
I have seen many coils schematics showing that the chokes must be grounded. The
only way I can think of doing this without all the transformer output going to
ground is to ground the choke by way of em induction. If there are any other
ways to do this please tell me.
I.e wrap the choke wire around a PVC cylinder and place the ground inside the
cylinder without it touching the choke wire. This would be good for when high
voltage/ frequency comes back to the transformer, but wouldn't the coke waste
input power even at low frequencies?
I've been able to find a NST rated at 10Kv -at- 60Ma. Trouble with this is that it
is actually made up of 2  -  5Kv Transformers connected in series. Since I do
not have the transformer yet I'm guessing that each separate one has an output
of 120Ma. I'm basing this on the capacitors connected in series affect of
doubling voltage but decreasing capacitance by the same ratio, the same affect
must apply to transformers connected in series. Is this right?
The transformer is old (don't know how old) so will it have any PCB's, I intend
to ask the dealer, but are there any laws in the UK against PCB's? If the
transformer does have them then I'm not buying it (asking price 35).
 
Thanks in advance
 
Tabraze Malik.