Hi Alan,
you seem to impute that there are no shortcommings in direct
sampling! :-))
Not at all,I just meant to emphasize the difference between the two
common SDR architectures,i.e.between the direct samplers and the
IQ mixer concepts.
The message was:
If SDR, then direct sampler.
and I do
own a couple very good conventional receivers
Here too.
If you're interested I can send you an audio file demonstrating
the reciprocal mixing on a E1800 and an Icom IC-7800
compared to Perseus (which doesn't show any RM in this setup).
73
Clemens
DL4RAJ
----- Original Message -----
From: "Alan Melia" <[email protected]>
To: <[email protected]>
Sent: Saturday, October 30, 2010 7:04 PM
Subject: Re: LF: RFspace SDR-IQ
Hi Clemens, you seem to impute that there are no shortcommings in
direct
sampling!
:-)) I suspect there are, but they are just "different". You may
be
right about the units mentioned, but it is just as easy to make a
poorly
preforming DSP radio as to make a poor analogue one. We are in
danger of
being conditioned to accept that "digital" is the magic dust that
solves all
problems......it is definitely not so!
Having said that, the performance of some units is quite remarkable
and I do
own a couple very good conventional receivers.
Alan G3NYK
----- Original Message -----
From: "Clemens Paul" <[email protected]>
To: <[email protected]>
Sent: Saturday, October 30, 2010 4:11 PM
Subject: Re: LF: RFspace SDR-IQ
Tony,
the most important difference between SDR-IQ/-IP(from RF Space)
or Perseus and the $200 SDR on
http://www.lazydogengineering.com/LD-1A_SDR.html
is that the latter is no direct sampling receiver.
It uses a downconverting technique with a number of
shortcomings,e.g.
phase noise of the LO and others.
I would go for a direct sampling SDR like those e.g. from RF space
or
Perseus.
73
Clemens
DL4RAJ
----- Original Message -----
From: "Tony" <[email protected]>
To: <[email protected]>
Sent: Saturday, October 30, 2010 3:49 PM
Subject: Re: LF: RFspace SDR-IQ
> Thanks guys.
>
> You have just tipped the balance for me and I shall be placing an
> order
> for one on Monday morning.
> It's about time I joined the 21st century, but it will be
> interesting to
> compare it to my beloved FT 102 rx.
>
> Tony, EI8JK.
>
>
> On 29/10/2010 16:50, Tony wrote:
>> Hello group.
>>
>> Has anyone any experience with this SDR ?
>> It looks interesting and I'm a bit tempted, especially as it
>> works
>> full spec down to 500 Hz and "usable" to 100 Hz.
>> But as I have never used an SDR, I haven't got a clue if it's
>> any
>> good
>> or not.
>>
>>
>>
>
>
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