A complete HPSDR transceiver

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An example of a complete HPSDR transceiver using the Mercury, Penelope, and Ozy boards and other available hardware and software. It concludes with test measurements that compare the finished transceiver to other commercially available high end transceivers.

By Ron Cox, W9KFB (with help from the HPSDR group who made all this possible)

Specifications

The goal was to build and operate the Highest Performance Amateur Radio Transceiver that can be assembled using components documented on this wiki. Specifically in one case/enclosure, the following is expected:

A totally integrated transceiver with an integrated computer, audio amplifier, speaker, HPSDR components, and 10 to 50 watts of power output. Not included would be the keyboard, mouse, flat panel screen, and antenna tuner. You could compare the proposed rig to commercial rigs such as the Flex 3000, TS-B2000, FT-2000, FT-950, or Ten Tec Pegasus. The transceiver must be mechanically and electrically secure so that one would not hesitate to take one to a field day exercise or a DXpedition as a primary rig.

Enclosure

Rear view of case prepared for installation of HPSDR components

It may be possible to build the rig in the HPSDR's Pandora's box. It is very possible to do so if you are using a laptop computer and can keep the RF powerout requirements to that needed for narrow band modes such as PSK31 and CW. That rig is being built, but two other rigs that were built came closer to meeting the specifications above. Using this experience, the specification goals will be met.

The following information on the Antec New Solutions Case was taken from their web site at [1]. In looking for a good case to build a transceiver that meets the specifications above and that allows you to access and modify the circuitry without getting in the way, we found that this case meets most of the requirements and delivers many unexpected bonus features. The specific Antec case is a model NSK2480 in the "New Solutions Series". Here are the main selling points about this case and power supply that sells for under $100 USD at most internet suppliers that carry Antec cases:

Power Supply

  • The power supply is acoustically quiet and highly efficient.
    The 80 PLUS® Certified EarthWatts 380W power supply
  • The 80 PLUS® Certified EarthWatts 380W power supply is also very quiet electrically and has no detectable switching power supply signals. If any spurious signals are detected in testing, we will eliminate them using clamp-on ferrites.
  • Universal input (100 - 240 volts at 6 Amps with 50 or 60Hz). This power supply must power all the HPSDR components that we put in this case.

Case Structure

  • 0.8 mm cold-rolled steel construction
  • Triple-chamber structure to isolate power supply and amplifier heat for cooler & quieter operation
  • 4 Drive Bays are used for HPSDR components, no optical or hard drives will be mounted here

The internal HDD trays are removed to allow room for HPSDR components (see photo).

  • 4 Expansion Slots - Only two will be usable as expansion slots because we will only use a Mini-ITX motherboard
  • Front-mounted ports for easy mike and earphone connections: 2 x USB 2.0 (example: Griffin Knob and/or USB DSP headset); Audio in and out (analog mike and headset)
  • Unit Dimensions: 5.5" (H) x 17.5" (W) x 16.3" (D); 13.97cm (H) x 44.5cm (W) x 41.4cm (D)

The height of the enclosure makes it possible to mount the HPSDR Atlas, Mercury, Ozy and Penelope boards.

Cooling Design

  • Advanced cooling system: 2 side mounted 120 mm TriCool™ 3-speed fans

The fans really only cool one of the three chambers, the one with,the computer mounted in it, but they are very low noise when set at low or medium speeds.

Motherboard Selection

From experience building several HPSDR transceivers in this case, we have found that all is needed is a small footprint Mini IPX motherboard. No extra I/O cards are required if one uses virtual software ports. By using SATA drive ports exclusively we can use such a small motherboard. The motherboard for this project was just ordered from newegg.com. The cost was $129.99 USD plus $6.98 USD for shipping. You can find information on the selected motherboard, an intel DQ45EK Desktop Board , at this website. [2]

CPU Selection

There are a large number of CPUs that are compatible with the DQ45EK board. One can spend up to about $370 for the latest and greatest intel Core2 Quad CPU or one can purchase a Core2 Duo CPU for about $69. The current list and the significant cache memory sizes and the operating frequencies are displayed at this website: [3]