It seems to me that I have seen stuff like this, but it was never
referred to in your terms. It is an old idea, back into vacuum tubes,
as mentioned.
The devil has always been in the details, and whether such stuff could
be manufactured reliably in quantity, and whether it would be rugged
enough to withstand real life, and whether it would have enough range
away from the extremes to create practical circuits for other than
conceptual demonstration. I'd always suspected that was never
overcome, since you can't buy them off the shelf at Radio Shack.
I don't own one but DX engineering does something off in that
direction with their active listening antennas. That's about as far
as I've seen anyone get.
73, Guy.
On Tue, Sep 14, 2010 at 3:37 AM, Andy Ikin <andrew.ikin@btopenworld.com> wrote:
> Guy,
>
> This link should work now.
>
> http://www.ieee.li/pdf/viewgraphs/matching_network_design_non_foster_impedances.pdf
>
> 73
>
> Andrew
> ----- Original Message -----
> From: "Guy Olinger K2AV" <olinger@bellsouth.net>
> To: "Andy Ikin" <andrew.ikin@btopenworld.com>
> Cc: <antennaware@contesting.com>
> Sent: Monday, September 13, 2010 11:51 PM
> Subject: Re: [Antennaware] Negative Impedance Converter NIC
>
>
> Hi, Andy. Thanks.
>
> However, attachments do not make it through the reflector. Please
> embed the link url in the text proper and resend.
>
> 73, Guy.
>
> On Mon, Sep 13, 2010 at 4:17 PM, Andy Ikin <andrew.ikin@btopenworld.com>
> wrote:
>> Guy,
>>
>> NIC stands for Negative Impedance Converter. These are active devices that
>> have a negative resistance i.e. the voltage is 180 degrees out of phase
>> with
>> the current.
>> They can be uses to cancel out either antenna capacitive or inductive
>> reactance to broaden the bandwidth; so called Non Foster Matching
>>
>> See attached link.
>>
>> Matching network design using non-Foster .
>>
>> 73
>>
>> Andrew
>>
>>
>>
>> ----- Original Message ----- From: "Guy Olinger K2AV"
>> <olinger@bellsouth.net>
>> To: "Andy Ikin" <andrew.ikin@btopenworld.com>
>> Cc: <antennaware@contesting.com>
>> Sent: Monday, September 13, 2010 8:07 PM
>> Subject: Re: [Antennaware] Negative Impedance Converter NIC
>>
>>
>> I'm probably not the only one...please define NIC. That comes up in
>> my head as Network Interface Card. 73, Guy.
>>
>> On Mon, Sep 13, 2010 at 2:38 PM, Andy Ikin <andrew.ikin@btopenworld.com>
>> wrote:
>>>
>>> Hello Folks,
>>>
>>> Is it possible to use NIC to overcome losses in terminated loop antennas?
>>> If so, how would one measure the NIC input impedance with say a Signal
>>> Generator and an Oscilloscope to check for correct NIC performance?
>>>
>>> 73
>>>
>>> Andrew Ikin G8LUG
>>>
>>> _______________________________________________
>>> Antennaware mailing list
>>> Antennaware@contesting.com
>>> http://lists.contesting.com/mailman/listinfo/antennaware
>>>
>>
>>
>>
>
>
> _______________________________________________
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> Antennaware@contesting.com
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