HI Tree,
Thanks for your input. I'm leaning towards a 2 element phased vertical
array with a quasi-cardioid pattern for my application. it will avoid any
phasing box overload issues.
73, Kenny K2KW
On Sun, Dec 17, 2023 at 2:12 PM Tree <tree@kkn.net> wrote:
> I think the concern about overload is another reason to not consider it.
> That box is not designed to handle a strong signal like another transmitter.
>
> One other solution is to try and come up with a coax length that presents
> an out of phase signal at the right amplitude to cancel it out on the 2nd
> receiver. I know W8JI has done this on 160.
>
> I have been successful with in-band receiving on 160 with a loop antenna
> about 800 feet away from the TX vertical with the null parked on the TX
> antenna. On 20 meters, I have done it with about 500 feet separation.
> It's obviously a lot easier with low power (like used in the NAQP). The
> K5KA muiti-ops used an all band vertical for RX for the in band radios.
>
> Tree N6TR
>
> Tree N6TR
>
> On Sun, Dec 17, 2023 at 10:41 AM Kenny Silverman <kenny.k2kw@gmail.com>
> wrote:
>
>> Thanks for all the comments, but knowing what the resulting antenna
>> pattern seems elusive.
>>
>> I need in-band RX antenna for a mult station. Typically antenna
>> separation, front-to-back and polarization are the main tools for that.
>> When I run out of room
>>
>> I was wondering if phasing from an NCC-2 box is another tool to consider.
>> But I don’t want to consider it without knowing what the resulting pattern
>> would be.
>>
>> Many thanks, Kenny K2KW
>>
>>
>> Regards , Kenny
>>
>> > On Dec 17, 2023, at 1:05 PM, Rick Kunath <k9ao@yahoo.com> wrote:
>> >
>> > I'm not sure we still understand the intended application of the
>> original poster, I know I don't.
>> >
>> > I've done lots of work with loops and loop arrays phased either
>> passively (active or entirely passive external phaser boxes) or actively
>> phased via an SDR but none of that would eliminate the need for RX
>> protection on the receive antenna and any electronics associated with it.
>> So if the OP is trying to get away from any protection from the TX energy,
>> I think this is false hope. A loop mounted preamp makes that more
>> complicated. And The NCC2 does have options for protection boards for TX
>> internally. There are several types available and also internal preamps.
>> But it cannot set a specific amplitude and phase angle on the phasing. I
>> don't have one and haven't ever had the pleasure of using one, but those
>> that do tell me they enjoy them and they work well especially for live
>> listening. I do like the idea of having the electronics at the shack end of
>> things and as little as possible at the antenna when possible, though
>> depending on the specifics you will have VACTROL devices or other
>> termination devices at at the antenna with at least some antenna types.
>> >
>> > Preset patterns and unattended work are another case entirely and this
>> is best done with specific phase coherent dual-channel SDRs and a specific
>> SDR application.
>> >
>> > I think doing what the OP might want as I might understand it is
>> possible, but I'd like to hear more from him about his hopes for the
>> project.
>> >
>> > Rick Kunath, K9AO
>> >
>>
>> _________________
>> Searchable Archives: http://www.contesting.com/_topband - Topband
>> Reflector
>>
>
_________________
Searchable Archives: http://www.contesting.com/_topband - Topband Reflector
|