PSK-series Transceivers

  PSK-20  PSK-30  PSK-40

new pic.jpg

 

Full instructions may be found under ‘documents’ on this web site

 

Click below for troubleshooting info:

http://smallwonderlabs.com/psk_docs.htm

(This document dates back to the original product release, but the transmitter RF strip has not changed appreciably since then.)

 

 

This design is a simplified variant of the 'PSK-20' design originally published in June 2000, QST magazine. It features an all new printed-circuit board and hotter driver and PA transistors for more robust power output. 

FEATURES:

Double-sided PCB 5.27" x 4.6", plated-thru-holes, solder masked/silkscreened for easy assembly
- interfaces with your computer's soundcard.

Built in audio isolation transformers/ VOX-switched.

Directly compatible with computer sound card interface- NO ‘RIGBLASTER’ REQUIRED.

- detailed 24 page Technical Manual for Assembly and Alignment Instructions,
- All on-board parts supplied in kit (as pictured above)

 

-      add a computer and a 50-ohm (nominal) antenna and you'll be on the air with PSK31
- no drift, no VFO tuning, no muss, no fuss!
 

-      The rig is crystal-controlled and was designed to work with the popular (and free!) ‘DigiPan’ software. Output power is 3-4W PEP. The crystal control provides excellent stability and its simplicity keeps the cost low. Performance characteristics for all PSK-series versions are similar.

Click below for free DigiPan software  (The PSK-series will work with many available software application- I suggest it only as a starting point if you don’t already have software)

http://www.digipan.net


Kit assembly is straightforward- there are only four toroids to wind! The number of adjustments is kept to the minimum consistent with good performance, and no special test equipment is needed to perform the alignment. There’s no harness wiring- all interface connectors mount on the rear of the circuit board. The board kit includes a 24-page manual with color figures. Step-by-step assembly instructions are included.


PSK-series Interfaces:


The interface cables to your computer are ‘off-the-shelf’ items, available from Radio Shack and other suppliers – there’s no soldering of adapter cables required and no extra interface units! Once the transceiver kit is assembled, it's 'plug-and-play'- operating adjustments are made via your computer.

The PSK-series board kit has an optional enclosure available, pictured above with top cover removed. The PSK-series board assembly slides directly into side rails in an extrusion enclosure.  It’s fixed to the rear panel via the BNC connector’s retaining hardware.   The enclosure and bezels are a handsome medium-grey finish. End panels are included- they’re a handsome black-anodized finish and are pre-punched and silkscreened.

 

-FREQUENTLY-ASKED QUESTIONS-

"What skills do I need to complete this kit successfully?"

I assume you’ve had some soldering experience (the instructions provide a 'refresher'). The instructions are comprehensive, and include component identification guides and toroid-winding instructions.  Detailed step-by-step instructions will guide you through the assembly process!

 

"What test equipment do I need?"

You'll need a HF wattmeter- A $30 Radio Shack SWR/Wattmeter is perfectly adequate for this project. Comparably-priced meters (e.g.MFJ) are also suitable.

It's also helpful to have another amateur rig (or frequency counter) to adjust a trimmer to provide accurate frequency calibration. Lacking this, the adjustment may be made by setting the trimmer for maximum on-screen PSK31 activity. All other adjustments are 'tune-for-maximum'. The alignment procedure is straightforward and is contained in the instructions.

 

"What else do I need to complete my station?"

- A PC (Pentium or equivalent- 100 MHz or better) with soundcard. The PSK-series transceivers interface with the MICROPHONE IN and LINE OUT jacks on the back of your computer. You supply a pair of standard 3.5mm stereo soundcard cables- available at your local electronics emporium.

- A 12 to 15V regulated DC supply capable of delivering at least 1 Amp of current. The instructions call out several popular candidates. Note that the garden-variety 'wall-wart' supplies are typically unregulated and are not up to the task. The PSK-series kit includes a power plug and 2' of cord to connect to a power supply.

-A 50-ohm nominal antenna cut to the operating frequency. At its simplest, this is a half-wave dipole antenna fed at the center with 50-ohm coax such as RG-58/U or RG-8/U. There are also a variety of vertical antennas available commercially.

 

"What if I run into trouble?"

Small Wonder Labs will answer your e-mail inquiries promptly. I recognize that I can't anticipate every possible question in the instructions, and your feedback helps me improve the product. Parts shortages are resolved by immediate shipment of make-up parts.

If you run into trouble during alignment and test, I'll guide you through the troubleshoot process as far as we can get by e-mail. If that doesn't do the trick, my repair person offers prompt and reasonably-priced service- he'll troubleshoot and repair the unit and let you know what he found.

 

Dave Benson, K1SWL
Small Wonder Labs
3/11/2010