Category: Reviews

Amateur Radio Projects and Software Defined Radio

Alinco DX-SR9 Hybrid SDR Transceiver Review

Introduction
If Alinco’s DX-R8  receiver and the DX-SR8 had a child, it would be the DX-SR9. The DX-SR9 inherits the brains of the DX-R8 and the brawn of the DX-SR8 to create the DX-SR9 hybrid amateur radio transceiver. Hybrid SDRs are generally a standard radio receiver with buttons and knobs that feature an IQ output to allow its use with SDR software programs. This gives you the best of best worlds. You get a radio with standard buttons and knobs that you can quickly use when you don’t feel like firing up the shack computer for SDR. The Hybrid SDR also allows you to use it in situations where you would like to not have to fool with the computer like in the field or mobile. Unlike the black box SDR radios, you are not always tied to a computer for operation. The Hybrids also offer a more friendly introduction to SDR for new users. They can plug the rig in and use it immediately and come to grips with the SDR part later. When SDR software is added, then the radio gains some of the features of far more expensive radios such as panoramic displays and additional filtering. What’s …

Studio1 SDR Software Review

Introduction
As you know, SDR radio basically consists of two components, the radio hardware and the software used to process the signal. As SDR radio hobbyists we typically spend a lot of time looking into the specs of the hardware, but we don’t but as much consideration into the software side of things. The software can be just as important as the hardware we choose to get good performance from a SDR radio system. We often turn to some of the free software offerings to get started in SDR hobby. While there is absolutely nothing wrong with that and we greatly appreciate the work these authors has put into their efforts. However, you have to keep in mind that some of these programs use DSP (Digital Signal Processing) engines developed for SDR use that have been handed down for many years and have only been improved slightly over their original incarnations.  With that in mind, the developers at  SDR Applications set out to create a new high performance DSP engine for better SDR performance from your SDR hardware. That product is now called Studio1 and is distributed by Woodbox Radio. Studio1 is not a free application. However, this is …

Ham it Up HF Converter

Introduction
How would you like to have a very good HF SDR receiver with a wide spectrum display covering 2MHz or more for about $75? Well, you can when you combine the Ham it Up HF Up-converter with a RTL2832U stick. NooElec is selling an HF Up-Converter board based on an open hardware design in conjunction with Opendous Inc. for about $50 plus shipping. The Up-converter board basically converts HF signals to the FM band (specifically 100.5 MHz to 150 MHz) allowing your RTL2832U to tune in the HF signals. When used in conduction with SDR Sharp or HDSDR you are able to receive HF signals in AM, USB, LSB, CW, and other modes. HDSDR gives you roughly the same functions found on most better HF receivers like noise blanking, automatic gain control, variable filters widths, etc. These inexpensive HF up-converters are nothing new. There have been many designs floating around in either DIY form or completed boards. However, the Ham It UP converter looks like the first product produced in quantity and is available  directly from NooElec in the US. I purchased the Ham it Up HF converter for testing from NooElec and it arrived very quickly.…

RTL2832U / R820T vs RTL2832U / E4000

The bad news is that the venerable RTL2832U / E4000 chipset DVB-T stick that has been the source of many SDR projects is getting a little harder find. The good news is that the new kid on the block the RTL2832U / R820T looks like a worthy replacement. The other advantage is the the RTL2832U / R820T is a bit cheaper. The RTL2832U / E4000 is typically selling from $25 – $35 while the RTL2832U / R820T sells for around $10 to $20. The frequency range of the RTL2832U / E4000 is generally around 64MHZ to 1700MHz with a gap around 1100MHz to 1250MHz. The RTL2832U / R820T frequency range is 24MHZ to roughly 1850MHz with no gaps (found yet), and no DC offset spike. RTL2832U / E4000 uses a Pal type antenna connector and adapters are easily found at your local Radio Shack for external antennas. …

The MK802 Android Mini PC and Ham Radio

Since the introduction of the $25 to $35 Raspberry Pi mini pc was introduced earlier this year, there has a flurry of small inexpensive pcs that have followed. One of the most popular mini pcs has been the Mk802 pc on a stick. While the Raspberry Pi can still be hard to get ahold off, the MK802s are readily available from US vendors. The MK802 ships with Android 4.0 installed. The prices for the MK802 pc runs around $60 – $70 dollars shipped. Even though the MK802 seems to cost about twice as much as the Pi, you are getting a little more for your money. The MK802 comes with a case, built in wifi, power supply, HDMI adapter cable, usb adapter, and a mini usb cable. So in the end they are pretty equally priced considering shipping for Pi and adding the cost of the power supply and other cables. Plus running Android, the MK802 is pretty much ready to go out of the box. The MK802 also has more built in memory and a slightly more powerful processor. Like the Pi the MK802. the MK802 can run several Linux distributions using that can be installed on a micro …

Softrock Ensemble RX TX VS Alinco DJ-X11

I thought it would be interesting to compare the $74 Softrock Ensemble RX TX kits’ receiver to the DJ-X11 wide-band portable SDR capable receiver. This is certainly an apples to oranges comparison and completely subjective. Unlike the Ensemble RX TX which has a receiver that is limited to reciever the three bands it is built for (although it will receive pretty well slightly out side of those bands), the DJ-X11 is a wide band receiver that covers AM, HF, VHF, and UHF bands. All the radios were tested with the same antenna (20 meter attic dipole), on the same bands with the same center frequency, and at the same time of day within a 30 minute time frame. HDSDR was used as the SDR decoder for both the Softrock Ensemble RX TX and the DJ-X11. HDSDR will not tune the DJ-X11, so the center frequency was set manually on the DJ-X11. I typically use PowerSDR-UI for the Ensemble, but it does not decode the IQ signal as well as HDSDR does for the DJ-X11. I sampled the center frequencies of WWV at 15.000MHz, 14.070 MHz, and  14.275 MHz for both radios. I also used the non-SDR Yaesu FT-450D which is …

5 Great Holiday Gifts for the Amateur Radio Operator

It’s that time of year again! When all those sparkly lights set the Amateur radio enthusiast thinking about what new toys they would like to see under the tree this year. Ham Radio Science would like to suggest a few ideas to fill that empty spot under the Christmas tree. These are a few products that we got to use over the past year that we thought were pretty great. Here we go!

Tigertronics Signal Link USB – $99

New to Amateur Radio digital modes or would you like to replace that homemade interface that you hacked together? You might want to check out the SignaLink USB from Tigertronics. Easy plug an play interface to your radio and computer. Just specify the proper interface cable for your radio when you order, plugin the cable to the radio, connect the usb cable to your computer and you are ready to go digital. You will need to make a few level adjustments to the audio input and outputs, but overall the SignaLink USB is very easy to set up. Since it has its own sound card built in, you won’t have to worry about unwanted sounds going out over the air. …