"Ron Baker, Pluralitas!" wrote in message
...

"RF Caused By SDR-IQ" wrote in message
. ..
There is a new Yahoo group
http://groups.yahoo.com/group/RFICausedBySDRIQ/ which may be of interest
to those who own or may purchase an SDR-IQ. The purpose of the group is
to exchange information about RFI caused by the SDR-IQ and how to reduce
or eliminate the RFI.

Is it interfering with itself or other devices.

If it is interfering with itself it is perhaps not surprising.
It is an interesting looking gadget but it is not a radio.
It has no front end. It is open to the whole 500 Hz
to 30 MHz all the time.

I take that back. The SDR-14 is known to have that
problem. The SDR-IQ block diagram shows some
front end filters.

If you have a strong AM broadcast
station near by or a ham or CBer in the neighborhood
their signal will override everything else. The SDR-IQ would
make a good IF/back end. Better results would be
obtained by connecting the SDR-IQ to the IF of another
receiver. Or by putting an RF preselector in front of it.

The TenTec RX-320D is about the same price but has a
real radio front end. Unfortunately the TenTec has
an RS232 rather than USB interface and the TenTec only
has a 12 kHz bandwidth.

--
rb

On Jun 2, 7:03 pm, "Ron Baker, Pluralitas!" wrote:
"Ron Baker, Pluralitas!" wrote in m...



"RF Caused By SDR-IQ" wrote in message
...
There is a new Yahoo group
http://groups.yahoo.com/group/RFICausedBySDRIQ/which may be of interest
to those who own or may purchase an SDR-IQ. The purpose of the group is
to exchange information about RFI caused by the SDR-IQ and how to reduce
or eliminate the RFI.

Is it interfering with itself or other devices.

If it is interfering with itself it is perhaps not surprising.
It is an interesting looking gadget but it is not a radio.
It has no front end. It is open to the whole 500 Hz
to 30 MHz all the time.

I take that back. The SDR-14 is known to have that
problem. The SDR-IQ block diagram shows some
front end filters.



If you have a strong AM broadcast
station near by or a ham or CBer in the neighborhood
their signal will override everything else. The SDR-IQ would
make a good IF/back end. Better results would be
obtained by connecting the SDR-IQ to the IF of another
receiver. Or by putting an RF preselector in front of it.

The TenTec RX-320D is about the same price but has a
real radio front end. Unfortunately the TenTec has
an RS232 rather than USB interface and the TenTec only
has a 12 kHz bandwidth.

--
rb- Hide quoted text -

- Show quoted text -

To me, the most striking thing about this little box is that it's
actually USB powered. So, it wouldn't require an independent power
supply or wall wart. That means you could run it off a battery powered
laptop after you lost power in a storm or something. I guess that's
kind of neat, but if it generates so much RFI that a new Yahoo group
has appeared just to discuss that fact, I wouldn't let this thing
anywhere near my house.

Steve

On Jun 2, 3:46 am, wrote:
On Jun 1, 10:39 pm, "RF Caused By SDR-IQ"
wrote:

There is a new Yahoo grouphttp://groups.yahoo.com/group/RFICausedBySDRIQ/
which may be of interest to those who own or may purchase an SDR-IQ. The
purpose of the group is to exchange information about RFI caused by the
SDR-IQ and how to reduce or eliminate the RFI.

Even with the link; it still makes little sense;

http://www.rfspace.com/sdriq.html

Why the hell don;t these guys tell us SDR stands for Software Defined
Receiver..

receiving Sonar and Sound ? Listening to Bats ?

- Why post here..

Who are these guys selling this thing to ?

The SDR-IQ :Software Defined Receiver" and Panoramic Adapter
http://www.rfspace.com/products.html
Coverage : 500 Hertz to 30 MHz
Modes : AM, WFM, USB, LSB, N-FM, DSB, CW & More
* All Digital - All Mode - "Plug & Play" Receiver
* Fully Adjustable DSP Filter Bandwidths
* Requires a PC for Power and Audio Output Processing
* Uses SpectraVue Software with a PC
http://www.rfspace.com/gallery.html
Offfered by RF Space .Com = http://www.rfspace.com/

Check-Out the SDR-IQ "Software Defined Receiver"
YAHOO GROUP: http://groups.yahoo.com/group/SDR-IQ/

QUESTION - Does the RF-Space SDR-IQ "Software Defined Receiver"
process Digital Radio Mondiale (DRM) Shortwave Radio Signals ?
DRM = http://www.drm.org/index.php
DRM RECEIVERS = http://www.drm.org/receiversequip/receiversequip.php

i want to know ~ RHF

In article .com,
Steve wrote:

On Jun 2, 7:03 pm, "Ron Baker, Pluralitas!" wrote:
"Ron Baker, Pluralitas!" wrote in
m...



"RF Caused By SDR-IQ" wrote in message
...
There is a new Yahoo group
http://groups.yahoo.com/group/RFICausedBySDRIQ/which may be of interest
to those who own or may purchase an SDR-IQ. The purpose of the group is
to exchange information about RFI caused by the SDR-IQ and how to reduce
or eliminate the RFI.

Is it interfering with itself or other devices.

If it is interfering with itself it is perhaps not surprising.
It is an interesting looking gadget but it is not a radio.
It has no front end. It is open to the whole 500 Hz
to 30 MHz all the time.

I take that back. The SDR-14 is known to have that
problem. The SDR-IQ block diagram shows some
front end filters.



If you have a strong AM broadcast
station near by or a ham or CBer in the neighborhood
their signal will override everything else. The SDR-IQ would
make a good IF/back end. Better results would be
obtained by connecting the SDR-IQ to the IF of another
receiver. Or by putting an RF preselector in front of it.

The TenTec RX-320D is about the same price but has a
real radio front end. Unfortunately the TenTec has
an RS232 rather than USB interface and the TenTec only
has a 12 kHz bandwidth.

--
rb- Hide quoted text -

- Show quoted text -

To me, the most striking thing about this little box is that it's
actually USB powered. So, it wouldn't require an independent power
supply or wall wart. That means you could run it off a battery powered
laptop after you lost power in a storm or something. I guess that's
kind of neat, but if it generates so much RFI that a new Yahoo group
has appeared just to discuss that fact, I wouldn't let this thing
anywhere near my house.

The purpose in life for this unit appears to be as a spectrum analyzer
not a radio receiver.

I'm sure if you put it in a good metal box with ferrite chokes on the
cables it would tame the RFI.

--
Telamon
Ventura, California

On Jun 2, 7:51 pm, RHF wrote:

QUESTION - Does the RF-Space SDR-IQ "Software Defined Receiver"
process Digital Radio Mondiale (DRM) Shortwave Radio Signals ?
DRM =http://www.drm.org/index.php
DRM RECEIVERS =http://www.drm.org/receiversequip/receiversequip.php

i want to know ~ RHF


If it does process DRM, there might be some way to disable this
function. Or perhaps it's possible to control the radio using third
party software that is not encumbered by DRM.

Steve

"Steve" wrote in message
oups.com...
On Jun 2, 7:03 pm, "Ron Baker, Pluralitas!" wrote:
"Ron Baker, Pluralitas!" wrote in
m...



"RF Caused By SDR-IQ" wrote in message
...
There is a new Yahoo group
http://groups.yahoo.com/group/RFICausedBySDRIQ/which may be of interest

snipola


To me, the most striking thing about this little box is that it's
actually USB powered.

Yeah, USB is pretty cool.

So, it wouldn't require an independent power
supply or wall wart. That means you could run it off a battery powered
laptop after you lost power in a storm or something. I guess that's
kind of neat, but if it generates so much RFI that a new Yahoo group
has appeared just to discuss that fact, I wouldn't let this thing
anywhere near my house.

I'm skeptical about the OP. He never responded to any other
posts. I checked out that yahoo group when he first posted and
it had one member. Checking now, yahoo says the group
doesn't exist.

It is still probably healthy to maintain a little skepticism about
the SDR-IQ too. It reportedly has switchable lowpass
and highpass filters at 5 MHz and 15 MHz. It seems they
would cover most desensitization issues. The 5 MHz
highpass filter should prevent desense due to nearby lower
frequency broadcast band stations. But if you've got a ham
in the neighborhood who keys up on either 40 or 20 meters it
seems to me that could desense the SDR-IQ to
everything from 5 MHz to 15 MHz.

It's interesting.
I'll be watching the reviews and this group.

--
rb

"Ron Baker, Pluralitas!" wrote in message
...

"Steve" wrote in message
oups.com...
On Jun 2, 7:03 pm, "Ron Baker, Pluralitas!" wrote:
"Ron Baker, Pluralitas!" wrote in
m...



"RF Caused By SDR-IQ" wrote in message
...
There is a new Yahoo group
http://groups.yahoo.com/group/RFICausedBySDRIQ/which may be of
interest

snipola


To me, the most striking thing about this little box is that it's
actually USB powered.

Yeah, USB is pretty cool.

So, it wouldn't require an independent power
supply or wall wart. That means you could run it off a battery powered
laptop after you lost power in a storm or something. I guess that's
kind of neat, but if it generates so much RFI that a new Yahoo group
has appeared just to discuss that fact, I wouldn't let this thing
anywhere near my house.

I'm skeptical about the OP. He never responded to any other
posts. I checked out that yahoo group when he first posted and
it had one member. Checking now, yahoo says the group
doesn't exist.

It is still probably healthy to maintain a little skepticism about
the SDR-IQ too. It reportedly has switchable lowpass
and highpass filters at 5 MHz and 15 MHz. It seems they
would cover most desensitization issues. The 5 MHz
highpass filter should prevent desense due to nearby lower
frequency broadcast band stations. But if you've got a ham
in the neighborhood who keys up on either 40 or 20 meters it
seems to me that could desense the SDR-IQ to
everything from 5 MHz to 15 MHz.

It's interesting.
I'll be watching the reviews and this group

Sounds very much like the front ends of most HF receivers. Both my Yaesu
FRG-7700 and my Kenwood HF transceiver have this type of rough bandpass
front end. I guess the days of tuned RF front ends have passed. I'm glad my
Grundig 600 has a preselector.

There are many SDRs available today; the Winradio G-series is possibly
the best known. The Flexradio SDR-1000 (now replaced) and the RF Space
SDR-14 and SDR-IQ have properties most other SDRs do not have; the
ability to record a large (up to 190 kHz) portion of the spectrum to a
PC hard drive. The recording can later be analyzed using different
demodulators, bandwidth settings etc.

Ordinary front end filtering is difficult to match with a 190 kHz
spectrum, hence one might need extra high-/lowpass filter or even
notch filters to avoid very strong signals.

The SDR-IQ does emit RFI on higher shortwave, masking very weak but
audible signals. I didn't know until I was informed about it but I
only use higher SW for listening to strong international stations.
There is no RFI on lower SW and MW. I don't know if this is also the
case with the SDR-14 and the Flexradio systems. For me the RFI is a
non-issue; for others it may be very important.

For me, the ability to record 19 MW channels into a file for later
analysis far outweighs the RFI and front end issues with the SDR-IQ.
Others may judge otherwise or have a more hostile RF environment.

"bm" wrote in message
ups.com...
There are many SDRs available today; the Winradio G-series is possibly
the best known. The Flexradio SDR-1000 (now replaced) and the RF Space
SDR-14 and SDR-IQ have properties most other SDRs do not have; the
ability to record a large (up to 190 kHz) portion of the spectrum to a
PC hard drive. The recording can later be analyzed using different
demodulators, bandwidth settings etc.

Ordinary front end filtering is difficult to match with a 190 kHz
spectrum, hence one might need extra high-/lowpass filter or even
notch filters to avoid very strong signals.

The SDR-IQ does emit RFI on higher shortwave, masking very weak but
audible signals. I didn't know until I was informed about it but I
only use higher SW for listening to strong international stations.

So you have one. Interesting.

There is no RFI on lower SW and MW. I don't know if this is also the
case with the SDR-14 and the Flexradio systems. For me the RFI is a
non-issue; for others it may be very important.

Every radio has its birdies. My TS-440 probably has about 20.
And I always have my CRT computer monitor on which
puts out spurs spaced 63 kHz through half of the HF band.

I wonder how strong and wide the interference from the
SDR-IQ is. Maybe it is normal. Maybe it will be reduced
once they go through FCC certification and the boxed version
is available.


For me, the ability to record 19 MW channels into a file for later
analysis far outweighs the RFI and front end issues with the SDR-IQ.
Others may judge otherwise or have a more hostile RF environment.


Yeah, the SDR-IQ has a lot of good applications.

Checking the TS-440, it covers HF with 10 filters of
varying width. One filter selects 0.5 to 1.5 MHz.
So when tuned to MW the whole
band is coming through the front end filter at one time.
A serious MW DXer might consider a preselector even
with an old style receiver.

I looked at the digital receivers a while back and pretty
much decided that I would go with the RX-320D when
I could afford to lose a week playing with a new toy.
But the SDR-IQ looks like it could go to the top of
the list.

--
rb

"Brenda Ann" wrote in message
...

snip


It is still probably healthy to maintain a little skepticism about
the SDR-IQ too. It reportedly has switchable lowpass
and highpass filters at 5 MHz and 15 MHz. It seems they
would cover most desensitization issues. The 5 MHz
highpass filter should prevent desense due to nearby lower
frequency broadcast band stations. But if you've got a ham
in the neighborhood who keys up on either 40 or 20 meters it
seems to me that could desense the SDR-IQ to
everything from 5 MHz to 15 MHz.

It's interesting.
I'll be watching the reviews and this group

Sounds very much like the front ends of most HF receivers. Both my Yaesu
FRG-7700 and my Kenwood HF transceiver have this type of rough bandpass
front end. I guess the days of tuned RF front ends have passed. I'm glad
my Grundig 600 has a preselector.

What kind of Kenwood do you have? I have
the TS-440. Hadn't thought about it before but
just read in the manual that it uses 10 filters to
cover HF. That is certainly better than the
SDR-IQ but it is conceivable that a
preselector would be advantagous with the
TS-440 is some situations.

There is a ham about a mile away that runs
25 W, PSK31, on 20 meters occasionally. When he
keys up everything else on my 3 kHz wide waterfall display
disappears. 20 meter falls in the range of the TS-440
10.5 to 14.5 MHz front end filter. I wonder if his
signal is desensing my receiver to everything in that
range. I'll have to check next time.

--
rb