Updating Classic Regenerative and Super Regenerative Circuits
Chuck Kitchin, N1TEV
Modern components allow Hams to modify the classic regenerative and super regenerative designs of the past. Ham radio experimentation is an excellent electronics teaching tool (as well as being FUN) and can lead to new discoveries in radio communications. This talk will cover the theory and modern applications of these classic circuits.
WSPRing Around the World
Joe Taylor, K1JT
Where in the world can your QRP signals be copied? With the WSPR computer program and a simple SSB transceiver, you can participate in a world-wide network of low-power stations exchanging beacon-like transmissions to probe potential propagation paths. Reception reports are uploaded in real time to a central database at WSPRnet.org, where you can see real-time signal reports and a world map of open propagation paths. WSPR uses techniques similar to those in the popular program WSJT, widely used for amateur communication by meteor scatter and "moonbounce".
The Midnight Loop — Theory and Practice of An Experimental Small Transmitting Loop
George Heron, N2APB and Joe Everhart, N2CX
The mysteries and science of STL antenna designs are explored by N2CX and N2APB, bringing a fresh approach to the classic limitations and introducing a state-of-the-art technology solution to this popular antenna topic. The first part of the presentation will overview theoretical design principles, to be followed by a practical working prototype for demonstration on 20 meters.
RF Filters: From Design to Construction and Testing
Dave Siegrist, NT1U and Bruce Beford, N1RX
A real-world low-pass filter for a 20M transmitter will serve as the backdrop for a discussion of HF filter types and designs. Dave and Bruce will walk through part selection, construction, and performance measurements of this filter during the talk. They will cover calculating values based on design goals, component choices and their impact on performance, and theoretical performance vs. real-world results.
Part 1. Dave Siegrist, NT1U
A discussion of RF filter design. Includes an overview of common filter types, their uses and characteristics. The design of a Chebyshev-type low-pass filter will be presented. Design methods will be introduced which use table values and filter design software to arrive at component values for the filter.
Part 2. Bruce Beford, N1RX
A specific filter design will be taken from the theoretical values through construction and testing. Component selection and its effects will be discussed. The filter is built with "real-world" components, and its performance measured and compared with the original design response.
QRP other bands, other modes, and large antennas
Allison Parent, KB1GMX
Strictly speaking, QRP has no implied band. But, it seems HF (especially lower HF) is home for most of QRP operations. You should know: QRP is great fun on the higher bands, too! In this talk we will discuss upper HF bands, VHF, and UHF QRP operation, and illustrate how some of the new digital modes have opened up new horizons and new challenges.
Something Old, Something New — A Medley of Ideas
Dave Benson, K1SWL
Do you ever feel the need for a break from ‘cookie-cutter’ QSOs? Rest assured, there is no end of interesting nooks and crannies within the QRP domain! This presentation takes a fond look at a ‘blast from the past’- AM operation on 75 meters. [This highlights a new product offering from Small Wonder Labs.] Not to neglect the newer modes, the talk also describes experiments with QRP SSB. The discussion also includes notes on simple QRSS operation and thoughts on circuit designs for the popular new WSPR mode.
Other presentation topics and information will be made available soon.