The Iowa QRP Group Presents:
The 30M WARCbler PSK-31
Rig Conversion Kit
By: Fred Spinner, W0FMS and Jeff Woods, W0ODS
(C) Copyright 2001, Fred Spinner and Jeff Woods -- All Rights Reserved

May 14, 2001

Part 5--


The NJ-QRP 80m Warbler is well suited for conversion to other bands, recognizing the limitations of a direct conversion design.  As long as the frequency is within the fundamental mode of oscillation of a crystal (up to about ~= 30 MHz) a Cohn filter can be designed to work with this simple, but elegant design.  The circuit otherwise is simple and should also scale to other frequencies.  Care should be taken in the adjustment of the rig so it is not overdriven, and the carrier (LO) suppression is adequate.

Our goal was to try to make a rig for a band that had not previously been covered by Small Wonder Labs or the NJ-QRP group, and do it for a reasonable price.  We think this goal has been realized with this "redesign" of the unit, and 30m is a good band to try to encourage operation on. We ordered the smallest amount of crystals we could at the "overseas factory" rate, and need to sell off sets of these crystals at nearly our cost.

This is why we are going to offer 15-20 sets of "PSK-30" rigs with the cooperation of the NJ-QRP group at Dayton initially.   A more concise "conversion manual" will be written before Dayton.  We will supply those of you who showed interest in "conversion kits" for the existing PSK-80's with crystals as soon as we return from Dayton.

If there is sufficient demand, we could order another set of crystals.  The lead time on these, however, are at least 6 weeks.  We will make the decision to do this based on the demand for the first set of conversion parts.  We are going to try to keep the pricing at $25 (hamfest pickup), or $30 shipped postpaid to the USA.  If there is overseas interest, please contact us and we will see what we can do.

To get the NJ-QRP PSK-80 kit, buy from the NJ-QRP website:

The total cost will be around $75 for the NJ-QRP kit and our conversion parts.  The "Dayton Special" in conjunction with the NJ-QRP group will probably be in the $55 to $60 range.

For further information on these kits, check this website, or contact:

Jeff Woods, W0ODS,
Fred Spinner, W0FMS,

Or SEE US AT Dayton!!!


More graphs, and computer models will be added here in the next week or so.  (Before Dayton)

About the "twisted pair":

Jeff Woods graduated from Rose-Hulman Institute of Technology with a BSEE in 1991.  Jeff has been an Extra class ham for years, and actually worked as a brass pounder for the merchant marines a few years ago.  Jeff now works for Rockwell Collins, Inc. Government Systems division, in Cedar Rapids, IA  Jeff previously worked for Kachina Communications, Inc. in Arizona, and in fact was the dude pictured on their sales brochures and QST ads a couple of years back...  Jeff did the circuit modifications other than the filter redesigns in this project, and ordered the crystals (what a guy!).  Jeff is lucky enough to still work with radio hardware for a living!

Fred Spinner graduated from Rose-Hulman Institute of Technology with a BSEE in 1992.  Fred has been a ham for years, and now holds an Extra class, but isn't much of a brass pounder.  Fred also works for Rockwell Collins, Inc. Government Systems division in Cedar Rapids, IA.  Fred does mainly software design at work, but he redesigned the filters for the rig.  "I thought my EE skills atrophied!  Guess not!", so quotith Fred. (They probably still atrophied, just didn't notice it this time!)

Fred and Jeff had one lunch hour that obviously was WAY too long.  Hence this project was born.  We will probably live to regret it!
(We have so far-  A fundamental truth in this universe:  "No good deed goes unpunished!")

Cheers!  72!

Fred W0FMS, Jeff W0ODS

May 14, 2001
Fred Spinner