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# Bias Tee with a Simulated Inductor

Discussion in 'General Electronics Chat' started by dmnchief001, Aug 9, 2012.

1. ### dmnchief001 Thread Starter New Member

Feb 9, 2012
2
0
Hi,
I recently built a Bias Tee to push an AC and DC signal through a 703 uH coil of mine:

As you can see in the schematic, the inductor on the top left allows the Direct current to flow through the coil. The capacitor on the top right allows Alternating current to flow through the coil at the resonant frequency of 60kHz:

The problem with the circuit is that I need almost 400kohm impedance at 60kHz to ensure that mostly all my alternating current flows through the coil in the middle of the schematic and not the inductor. To ensure this 400kohm impedance, my inductor has to be ONE HENRY. I know that this is a LOT! Also, my inductor has to be able to pass ONE AMP, because my coil needs 1 amp of direct current.

I have built this circuit in real life using a 193S inductor, and everything works great. The problem is that the inductor is HUGE!!!

So here is my question:
Is it possible to replace the huge 1H and 1Amp inductor I have in the circuit with a simulated inductor?

I've been trying to use PSPICE to model the simulated inductor with little success:

As you can see, there is NO direct current flowing through my coil. The AC still flows through the core, unless I decrease the 100kohm resistor.

Does anyone have any advice on how I can use the simulated inductor to push one amp of direct current through my coil and block the alternating current from my other source?

2. ### t_n_k AAC Fanatic!

Mar 6, 2009
5,448
790
How about replacing the 1H inductor with a parallel resonant branch as in attachment.

• ###### Inductive T divider question.jpg
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17.1 KB
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#12 likes this.
3. ### #12 Expert

Nov 30, 2010
18,076
9,691
at first look, this appears to be brilliant.

Feb 9, 2012
2
0
5. ### #12 Expert

Nov 30, 2010
18,076
9,691
1,630 heads are better than 1!