 |
Background:
Software Defined Radio (SDR) is
a collection of hardware and software technologies that enable
reconfigurable system architectures for wireless communications.
SDR provides an efficient and comparatively inexpensive solution
to the problem of building multi-mode, multi-band,
multi-functional communications devices that can be enhanced using
software upgrades. As such, SDR can really be considered an
enabling technology that is applicable across a wide range of
areas within the wireless industry.
SDR-enabled communications
devices can be dynamically programmed in software to reconfigure
the characteristics of equipment. In other words, the same piece
of "hardware" can be modified to perform different functions at
different times. This allows the manufacturer to concentrate
development efforts on a common hardware platform.
The SDR-1000:
The
SDR-1000, from
Flexradio. is a
complete Software Defined Radio (SDR) transceiver interface to a
Personal Computer. It provides everything needed to convert
a PC into a high performance, 11KHz-65MHz general coverage
receiver with 160M-6M (2M optional) Amateur Radio band transmit
capability. The SDR-1000 is described in detail in a four
part
article series in QEX Magazine.
With the new RF Expansion Board (RFE), the SDR-1000 offers world
class >90dB third-order IMD dynamic range (depending on sound card
quality) and -141dBm MDS in a 500Hz bandwidth. To learn more
read the
RF Expansion Board data sheet.
The
SDR-1000 incorporates a novel
Quadrature Sampling Detector
to provide high dynamic range with minimal components. An
Analog Devices AD9854 quadrature DDS and 200MHz 1ps jitter clock
oscillator provides continuous coverage with very low phase noise.
The SDR-1000 delivers 100W PEP on the 160-10m (50W 60m) HF bands
with the optional SDR-100WPA linear amplifier. Without the
amplifier, it provides 1W PEP on HF and 500mW on 6m. The
SDR-1000/RO is a receive only version that does not include the
RFE board. We also accept custom orders for receive only
versions that include the RFE board where the 1W amplifier has
been disabled.
Click
HERE
for W5GI's recommendations for configuring the SDR-1000
for optimum voice transmission .
Flexradio Achieve:
(Email sent to the Flex Radio reflector enabling other SDR-1000
users to read what I had to say about audio and other issues.)
06/18/05
After extensive testing with various
input devices-from sophisticated audio enhancer's to just
turning up the pre amp gain in the setup screen, I've
concluded that an external pre-amp is preferred to either a
second sound card or direct connection of mic [to D44] and
increasing the pre-amp to over 50.
My external system consists of a
Behringer UB-802 Mixer that sells for $50 or less. It has 6
inputs and 6 outputs. It also has 2 pre-amps and provisions
for aux equipment. This mixer works well with all the Heil
microphones and even less expensive mics. The mixer also has
a 3 band EQ which really helps-especially with the Heil
mics. I highly recommend this little gem for those who
what/need a pre-amp and want exceptional transmit audio.
The mixer can be purchased from the
Guitar Center in most major cities or over the Internet from
places like Musicians Friend.
w5gi
06/18/05
I just created different datum bases
for each of my operating interests. For example, I have a
database for 40 meters SSB using conventional filter
settings for both receive and transmit, compressor set to
3 db, and all other variables set for typical 40 meter SSB
operation. Conversely, I have a 20 meter database for
Hi-FI operation that uses wider filters in both receive
and transmit and no compression. I also made a DX
database with narrower filters, some equalization and more
compression.
The process was simple- I saved the
database I developed, then renamed it.
If you would like to download one or
more of my data bases, simply click on any one of the
following:
PS-now I would like to see a button
that will allow "one-step" selection of any saved data
base without having to go to the setup screen to import a
new data base.
PS-no other radio on the market has
this capability to SAVE ALL SETTINGS!
FlexRadio mailing list:
FlexRadio@flex-radio.biz
http://mail.flex-radio.biz/mailman/listinfo/flexradio_flex-radio.biz
|
|
|
Copyright © 2004
JOHN P BASILOTTO, W5GI
(512) 608-6727
w5gi@aol.com
|
|
|
|
|
