Hi Mike
Op32 with dynamic search is a fantastic tool indeed. Despite of the "fantastic"
false decodes from time to time !
But those can be easily discharged, specially when having local reports of the
Tx station
I made an experiment comparing Op2H (no deep search) with Op32 and it showed
out that both modes perform very similar
The experiment was made transmitting with U3 consecutive frames in Op32 and
Op2H. I'm using a mechanically adjustable
vertical antenna so trimmed it down in order to get just a signal hardly
decoded on my monitor QTH at 7Km
It is amazing to check how just a little of vertical antenna height increase
can boost the Tx signal ! :-)
I set the results in an small Excel you can get here
https://dl.dropboxusercontent.com/u/7162072/Docs/Pruebas%20Op2H%20versus%20Op32.xls
The question is .... What should be expected from a Op2H with Dynamic Search ??
73 de Luis
EA5DOM
-----Mensaje original-----
De: [email protected]
[mailto:[email protected]] En nombre de Mike Dennison
Enviado el: martes, 19 de mayo de 2015 12:16
Para: [email protected]
Asunto: Re: LF: 23:16 136 G6AVK de EB3FRN-1 Op32 Deep Search 725 mi -40 dB
Well, I am running around 400mW ERP (as stated on my Opera beacon) from a
transmitter with 800W RF output giving 3,2A into an inverted-L 14m high with
5x14m parallel top wires. Antenna efficiency (assuming 80% tx PA efficiency) is
0.05%.
I imagine G6AVK is running a lot less - from the reports it must be about 70mW
ERP which suggests perhaps 0.1% antenna eficiency. His successes show how
useful Op32 is.in producing reception at 1000km+ with that power level.
Mike, G3XDV
===========
> There is a interesting question ..
>
> Two LF stations , quite close , similar times , Colin running
> 80 watts carrier power..
>
> what power / Ae efficiency difference produced + 7
> and +8 dB at the Rx's ?
>
> 73-G
>
>
> Rx at Mon, 18 May 2015 00:34:21 GMT
> From G3XDV by DF1VB/3 Loc JO31SK
> Frequency: 0.136 MHz (2200m), OPERA, -33dB
> Distance: 536 km bearing 91°
>
>
> Rx at Mon, 18 May 2015 00:34:21 GMT
> From G3XDV by EB3FRN-1 Loc JN01MC
> Frequency: 0.136 MHz (2200m), OPERA, -32dB
> Distance: 1194 km bearing 174°
> Using: Opera v1.5.7/Rptr V1.6
> Antenna: RX Op32
>
>
>
> From: Graham
> Sent: Monday, May 18, 2015 12:31 AM
> To: [email protected]
> Subject: LF: 23:16 136 G6AVK de EB3FRN-1 Op32 Deep Search 725 mi -40
> dB
>
>
> Just 80 watts , just on the Op32 decode limit , dynamic with 5
> dB in hand ?
>
> 73-G,
>
> 23:16 136 G6AVK de EB3FRN-1 Op32 Deep Search 725 mi -40 dB in Montbrio
> with .w + Bottom loaded Inverted L 11m x 21m
>
> 23:16 136 G6AVK de DF1VB/3 Op32 Deep Search 297 mi -40 dB in Dortmund
> with .w + Bottom loaded Inverted L 11m x 21m
>
>
>
>
>
>
>
>
>
>
>
> From: Graham
> Sent: Saturday, May 16, 2015 12:36 AM
> To: [email protected]
> Subject: LF: 22:54 136 G6AVK de DF1VB/3 Op32 Deep Search 297 mi -41 dB
> in Dortmund
>
>
>
>
>
>
> -----
> No virus found in this message.
> Checked by AVG - www.avg.com
> Version: 2015.0.5941 / Virus Database: 4342/9815 - Release Date:
> 05/19/15
>
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