----- Original Message -----
. .
More to the topic, I have a Grundig Aviator G6 and also a Grundig G8.
I'll have to give one or both a try with Perseus running on my
MSI Wnd U123 NetBook. Should be fun.

Jeff, WB1AAL

----- Original Message -----
From: "thinkdx" <dx@...>
To: <ultralightdx@...>
Sent: 04 August 2011 18:39
Subject: [ultralightdx] Re: Could the iPhone become an Ultralight ?


Hi Jeff,
A number of Perseus SDR owners have used Atom-powered netbooks
successfully; it's a matter of configuring settings properly. I owned
the first gen MSI Wind U100 to process IQ and listen to audio, and with
a correctly interfaced hard drive you can record up to 1600 khz
bandwidth using Perseus and the U100 (the internal drive or eSATA
connection is best).
Bjarne Mjelde, who runs the arcticdx.blogspot.com
<http://arcticdx.blogspot.com/> blog, also used the MSI U100 fine with
his Perseus and a Winradio SDR I believe. He wrote about it on his blog.
When I had my Five Below blog for Perseus online, I covered in detail
the use of the MSI netbook and the Perseus SDR together. You may find
this spreadsheet of interest. It covers various configurations of AC vs
DC power, hard drive types, and Atom CPU overclocking settings (the U100
had a factory bios available that permitted up to 24% overclocking):
http://www.mediafire.com/file/numho5gxxty/msi_wind_perseus.zip <Hi
Jeff,A number of Perseus SDR owners have used Atom-powered netbooks
successfully; it's a matter of configuring settings properly. I owned
the first gen MSI Wind U100 to process IQ and listen to audio, and with
a correctly interfaced hard drive you can record up to 1600 khz
bandwidth using Perseus and the U100 (the internal drive or eSATA
connection is best). Bjarne Mjelde, who runs the arcticdx.blogspot.com
blog, also used the MSI U100 fine with his Perseus and a Winradio SDR I
believe. He wrote about it on his blog.When I had my Five Below blog for
Perseus online, I covered in detail using the MSI netbook and the
Perseus SDR together. You may find this spreadsheet of use, in which I
compared various configurations of AC vs DC power, hard drive types, and
Atom CPU overclocking settings (the U100 had a factory bios available
that permitted up to 24%
overclocking):http://www.mediafire.com/file/numho5gxxty/msi_wind_perseus\;
.zip>
A key observation is that if you don't want or need recording the SDR's
bandwidth to hard drive (for later demodulation, filtering, & DXing
across the entire band), the processor requirements really aren't that
great.
What SDR software were you using to try and decode the IQ data from your
Alinco? Maybe it's more demanding than the Perseus software.
This is getting off topic somewhat from ULRs, so if I can give you any
further details regarding the MSI Wind netbook and SDRs, please contact
me offline.
Guy AtkinsPuyallup, WA USA


--- In ultralightdx@..., Jeffrey Fritz <jnfritz07@...>
wrote:

I can second what Charles said about a notebook used as an SDR--only

in my case I tried using an MSI Wind U123 NetBook to process an IQ feed
from my Alinco DX-R8 receiver.

The U123 does have a stereo microphone in so that wasn't an issue. But

even if it had been, I have a Berringer USB Audio Interface that can
handle stereo audio in. The problem was that, as Charles reported, the
Atom CPU simply didn't have enough processing power to keep the SDR
application working properly.

On a related topic, I have iSDR running on my iPad. Perhaps that could

be used as well, but I suspect that, like the iPhone, the iPad also has
only mono audio in.

73,

Jeff, WB1AAL

--- In ultralightdx@..., Jeffrey Fritz wrote:
>
> I can second what Charles said about a notebook used as an SDR--only in my case I tried using an MSI Wind U123 NetBook to process an IQ feed from my Alinco DX-R8 receiver.
>
> The U123 does have a stereo microphone in so that wasn't an issue. But even if it had been, I have a Berringer USB Audio Interface that can handle stereo audio in. The problem was that, as Charles reported, the Atom CPU simply didn't have enough processing power to keep the SDR application working properly.
>
> On a related topic, I have iSDR running on my iPad. Perhaps that could be used as well, but I suspect that, like the iPhone, the iPad also has only mono audio in.
>
> 73,
>
> Jeff, WB1AAL
>

--- In ultralightdx@..., Jeffrey Fritz <jnfritz07@...> wrote:

I can second what Charles said about a notebook used as an SDR--only in my case I tried using an MSI Wind U123 NetBook to process an IQ feed from my Alinco DX-R8 receiver.

The U123 does have a stereo microphone in so that wasn't an issue. But even if it had been, I have a Berringer USB Audio Interface that can handle stereo audio in. The problem was that, as Charles reported, the Atom CPU simply didn't have enough processing power to keep the SDR application working properly.

On a related topic, I have iSDR running on my iPad. Perhaps that could be used as well, but I suspect that, like the iPhone, the iPad also has only mono audio in.

73,

Jeff, WB1AAL

--- On Tue, 8/2/11, nz0i wrote:

From: nz0i
Subject: [ultralightdx] Re: Could the iPhone become an Ultralight ?
To: ultralightdx@...
Date: Tuesday, August 2, 2011, 10:46 AM

 

--- In ultralightdx@..., "Michael" wrote:
>
> What would be the lowest-spec notebook that would do it for an
> uldx maverick?

Notebook computers suffer from the same problem as cell phones: you've got to find one that offers stereo microphone input. Too often notebooks skimp on the sound card, and offer only a mono microphone input.

I would recommend doing plenty of homework before deciding to buy a notebook for SDR use. Check with knowledgeable SDR enthusiasts on some of the SDR groups for their recommendations.

73,
Charles
NZ0I

----- Original Message -----
From: "nz0i" <charles.scharlau@...>
To: <ultralightdx@...>
Sent: 02 August 2011 17:32
Subject: [ultralightdx] Re: Could the iPhone become an Ultralight ?



One more comment on this thread...

The iSDR iPhone app utilizes the same digital signal processing techniques found in PC-based SDR
receivers. It does frequency domain filtering using a theoretical "brick wall" sinc filter algorithm
to provide steep and deep bandpass filtering.

iSDR doesn't utilize any DSP hardware, but instead uses the iPhone/iPod/iPad processor to implement
the DSP algorithms. It does all of its work at audio frequencies, so the receiver RF performance
will depend largely on the quadrature sampling detector and antenna that you use with iSDR.

The fact that iSDR works on audio frequencies provides an advantage that is not documented, and not
widely known: iSDR can convert your iPhone into a stand-alone high-performance audio filter. And it
can do so with no specialized accessories or equipment to build or purchase. Just install and run
the iSDR app on your Apple iOS product, connect some earphones, and configure iSDR to use external
audio input. Place the microphone next to your ultralight receiver, then tune and adjust iSDR's mode
and filter settings for optimum listening.

iSDR provides CW filtering down to 100 Hz. The SSB and AM filters are also adjustable. It should add
some selectivity to ultralights that are lacking in that regard. It should also perform the function
of a rudimentary panadapter, allowing you to view the narrow signals embedded in the audio spectrum
coming from your ultralight's speaker.

73,
Charles
NZ0I

--- In ultralightdx@..., "Michael" <michael.setaazul@...> wrote:

Thanks for your informed input, Charles. Very helpful.
Can you suggest links to diy RF frontend designs?
What aerial and frontend configuration is necessary
for the iPhone DSP to equal a DSP uldx with, say,
a MW 7½" external ferrite as featured on this site?

Michael UK

----- Original Message -----

From: "nz0i" <charles.scharlau@...>
To: <ultralightdx@...>
Sent: 01 August 2011 17:35
Subject: [ultralightdx] Re: Could the iPhone become an Ultralight ?


I meant to mention one more thing: regarding SDR on other devices, like Android, Webos, QNX,
Symbian, etc.

The main thing preventing SDR on those devices is the lack of stereo microphone input. Note: I say
mic *input*, not stereo earphone output. In-phase/quadrature detection requires two input signals,
each 90-degrees out of phase relative to one another. So stereo input is required -- though for
amplitude modulation modes (AM, SSB, CW) the software can do the detection using just a single input
signal. But I digress.

If you hear of any other portable programmable device, other than an iPhone, iPod touch, or iPad,
that accepts external stereo microphone input, please let me know. For now, I'm aware of no Android
products or any other programmable handheld devices that can support full I/Q stereo input.

73,
Charles
NZ0I

---------------------- In ultralightdx@..., "nz0i" <charles.scharlau@> wrote:

By purchasing a used or refurbished iPod touch, and building the RF front-end yourself, you MIGHT

be able to set yourself up with an SDR receiver using iSDR for under $100. You can also get an
iPhone 3Gs for around $50 with a 2-year contract in the USA - but of course the monthly charges
would put the total cost WAY over $100.

Since all the Apple iOS devices are designed primarily to serve other functions (phone, music

player, etc), and require a special app and hardware to turn them into MW receivers, I guess they
will always fail to fully adhere to the strict definition of an ultralight.

Still, iSDR can provide a remarkably high level of performance in a very portable package. And if

you happen to already own a compatible Apple device, then the cost to you is very low indeed.

73,
Charles
NZ0I

------------------------------------

----- Original Message -----

From: "nz0i" <charles.scharlau@...>
To: <ultralightdx@...>
Sent: 01 August 2011 17:35
Subject: [ultralightdx] Re: Could the iPhone become an Ultralight ?


I meant to mention one more thing: regarding SDR on other devices, like Android, Webos, QNX,
Symbian, etc.

The main thing preventing SDR on those devices is the lack of stereo microphone input. Note: I say
mic *input*, not stereo earphone output. In-phase/quadrature detection requires two input signals,
each 90-degrees out of phase relative to one another. So stereo input is required -- though for
amplitude modulation modes (AM, SSB, CW) the software can do the detection using just a single input
signal. But I digress.

If you hear of any other portable programmable device, other than an iPhone, iPod touch, or iPad,
that accepts external stereo microphone input, please let me know. For now, I'm aware of no Android
products or any other programmable handheld devices that can support full I/Q stereo input.

73,
Charles
NZ0I

---------------------- In ultralightdx@..., "nz0i" <charles.scharlau@...> wrote:

By purchasing a used or refurbished iPod touch, and building the RF front-end yourself, you MIGHT

be able to set yourself up with an SDR receiver using iSDR for under $100. You can also get an
iPhone 3Gs for around $50 with a 2-year contract in the USA - but of course the monthly charges
would put the total cost WAY over $100.

Since all the Apple iOS devices are designed primarily to serve other functions (phone, music

player, etc), and require a special app and hardware to turn them into MW receivers, I guess they
will always fail to fully adhere to the strict definition of an ultralight.

Still, iSDR can provide a remarkably high level of performance in a very portable package. And if

you happen to already own a compatible Apple device, then the cost to you is very low indeed.

73,
Charles
NZ0I

------------------------------------

--- In ultralightdx@..., "nz0i" <charles.scharlau@...> wrote:

By purchasing a used or refurbished iPod touch, and building the RF front-end yourself, you MIGHT be able to set yourself up with an SDR receiver using iSDR for under $100. You can also get an iPhone 3Gs for around $50 with a 2-year contract in the USA - but of course the monthly charges would put the total cost WAY over $100.

Since all the Apple iOS devices are designed primarily to serve other functions (phone, music player, etc), and require a special app and hardware to turn them into MW receivers, I guess they will always fail to fully adhere to the strict definition of an ultralight.

Still, iSDR can provide a remarkably high level of performance in a very portable package. And if you happen to already own a compatible Apple device, then the cost to you is very low indeed.

73,
Charles
NZ0I

--- In ultralightdx@..., Graeme Zimmer <gzimmer@...> wrote:

ferrite61 wrote:

OK, thanks Graeme. Seems to be nothing more than an audio processor/amp. Or does it actually have IF filtering?

The next step in the evolution of radio technology involves "Direct
Conversion" (or "Phasing") type receivers and transmitters.

Single Signal Direct Conversion rigs have been around forever, but until
recently have not been entirely practical due to the difficulty of
constructing accurate Quadrature Oscillators and 90 deg audio phase
shifters.

DDS oscillators and Digital Audio processors has completely changed all
that and so we are seeing a revolution in radio design under the name
"Software Radio".

The first step was to use a PC to do the audio processing, but
increasingly we are seeing small stand-alone processors which can do the
work. Using an iPhone is a brilliant step in that direction.

Most of the modern cellular phones use this "Direct Conversion"
technology, as does the little Si4734 "SDR-on-a-chip" IC which makes
your UltraLight class possible. The Superhet is now dead and buried.

So the question "does it actually have IF filtering?" is pretty much
meaningless, as the technology avoids the use of IF filtering entirely.

It does all the bandpass processing at Audio frequencies.

......... Zim

--- In ultralightdx@..., Graeme Zimmer <gzimmer@...> wrote:

> I need some clarity on this.

It's explained very clearly on the web site.

specifically:

"iSDR does not require Internet connectivity, a cellular network,
Bluetooth, or WiFi. What you will need in order to receive live signals
is an external device (known as an "RF front-end") that converts radio
signals into audio signals that can be fed into the iPhone's microphone
input"


............ Zim