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[linrad] Fwd: Re: Sometimes You Feel Like a Nut

>At 01:55 AM 5/3/2005 +0200, you wrote:
>Hello Mike,
> >It is like Alice in the Wonderland. What do you want to do?
>Leif, many thanks for the reply. At this point I would like to use Linrad 
>in it's most rudimentary form. Initially I want to use the output of my 
>receiver in normal SSB bandwidth, and reduce line noise etc (as much as 
>possible with the inherent bandwidth limitations) on 2 meter tropo. I also 
>want to take the output of Linrad(from a dedicated computer) and feed it 
>into another computer running JT65B on 2 meter EME, once again to reduce 
>local noise. There are a couple of other possibilities:
>1) I am currently taking the 10.7 mHz IF output from a IC-271A 2 meter rig 
>and feeding it into my FT-1000MP. Front end
>NF = approx 0.25 dB, plus another approx 0.2 dB line loss. That 10.7 mHz 
>bandwidth is about 18 kHz. I have considered the possibility of mixing 
>that signal down to baseband and into Linrad.
>2) The other consideration is to take the 28 mHz output from a 2 meter 
>converter(nice and broad) and mix that to baseband.
> >First of all you are limited by your hardware. The frequency, bandwidth 
> sensitivity and dynamic range is determined by analog >hardware. Without 
> knowing what you have and what kind of signals you want to look for I 
> just can not answer the
> >first question.
>In addition to the above RF equipment, computer hardware is a 500 mHz AMD 
>K6-2 and a 16 bit ISA Soundblaster. I have purchased a 24 bit PCI 
>Soundblaster Live card, and it should be online by the weekend.
> >How do I turn the noise blanker on? This depends on your situation. What 
> bandwidth do you use, what is the dynamic range of your >hardware and so on.
>I don't have the foggiest idea about the dynamic range of the 
>hardware.  Are we talking about computer hardware or RF hardware.  Being 
>of a Windows mind-set, I want to click a button that says "turn the 
>blanker on and enjoy".
> >In case you use 2 kHz bandwidth from the loudspeaker output of a radio 
> on which you can not turn off the AGC, Linrad can
> >not do the blanking particularly well. It then depends on the repetition 
> rate of the pulses and the AGC characteristics
> >of the analog receiver.
>I can turn the AGC off in the FT-1000MP, but not in the IC-271.
> >MS Windows version will behave exactly the same - at least to start with 
> I think.
>That would be OK, however, I would expect that with a windows version, I 
>would be free from the miseries of roots, owners, users, permissions, 
>dependencies, multiple variations of the OS who do not always like each 
>other, and line after line of hand entered code, thus leaving more time to 
>concentrate on the software itself.
> >I hope you have already taken some steps forward by help of the 
> information that Roger, W3SZ supplied.
>Yes, I started reading that and printed several pages to read. Since I 
>started trying to understand Linux and Linrad, I have printed enough 
>information to form a stack about two inches high, plus what I read online 
>and didn't print.
> >You are in command.
>Thanks for your generous complement, but right now this is clearly not the 
>case. We have a saying here in the southern US:
>"he is like a blind dog in a meat cooler". Yep, that pretty well sums it up.
>  Thanks again, I will keep reading.

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