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40M High Performance
Superhet Receiver
Designed by Jim Kortge, K8IQY

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This kit has been retired. Thank you for your support

SS Announced at OzarkCon 2011 - HT announced at OzarkCon 2014           
Kitted and Offered For Sale By The Four State QRP Group        

The SS-40HT high performance receiver is the latest design from Jim Kortge, K8IQY. Modified for interfacing with the SS-40TX transmitter strip, it is an evolution of the SS-40SS. SS stands for "Stable and Sensitive". It exhibits the signature IQY extremely quiet amplifier chain. Disconnect the antenna and the receiver's noise floor is almost undetectable. A matched crystal IF filter provides a steep sided 500 cycle bandpass and outstanding opposite sideband rejection. Covering the 40M QRP "watering holes", a Super VXO provides 25-30 kHZ of smooth stable tuning, and no perceptible drift even from a cold start. While easy to build, this is not a trivial kit. There are 150 parts, and when completed the resulting high quality receiver is a pleasure to use.

Originally intended as a companion receiver for the NS-40 transmitter, the HT version interfaces with the new SS-40TX transmitter strip to create a high prformance transceiver. The HT may also be used with a Magic Box TR system between it and an NS-40 allowing effortless transceiving.

First time builders please note: This kit is not difficult to build. All parts are through hole except the main mixer, which is an easy to solder large footprint SMT part. The parts are wide spaced on the board making installation easy, and all connectors are board mounted which eliminates point to point wiring. After all the parts are installed it's ready to try out.

Specifications and Design Features
Sensitivity (MDS): -132 dBm  Spectacular, nearly all the big rigs on this list  are less sensitive (without their preamps) than is the SS-40.
Selectivity: 500 Hz IF Filter with great skirts.
Opposite Side band Rejection: Outstanding, greater than 50 dB!
Noise floor: Incredibly quiet! 45 dB below the 40M average noise floor, and 20dB quieter than the famed 2N2 series.
Audio stage: Drives speakers to undistorted, clean, room filling volume, or use earphones.
Tuning Range: 25-30 kHz of stable, smooth, and easy tuning.
Super VXO: Three crystals and NO PERCEPTIBLE DRIFT! Not even from a cold start!
Audio Derived AGC: That is smooth, very effective, pleasant to hear, and easy on the ears.

SS-40HT Assembly Manual For kits shipped since 1 April 2014.
SS-40 Assembly Manual, For kits shipped since 27 June 2011
Assembly Manual In Spanish Translation by Jon Iza EA2SN, thank you Jon.
Assembly Manual In Japanese Translation by Kyonosuke Hiroi JHØCCK, thank you Kyonosuke-san.
Assembly Manual, 5K Tuning Pot Version For kits shipped before 15 June 2011
Radioafionados Article. Authored and Translated by Jon Iza EA2SN, thank you Jon.
Assembly Manual In Spanish, 5K Tuning Pot Version Translation by Jon Iza EA2SN, thank you Jon.
Click to download WB8RCR's Dial Maker program. A generic dial can make an effective
frequency dial when used with a calibration chart such as this one.
K9PL's Review  in the K9YA Telegraph  (posted here with permission)  Thank you Philip.
Elecraft's Excellent Capacitor Identification Page  Posted with permission.
Electronics 2000 Resistor Code Graphic calculator  Posted with permission.
Ten Tec TP-41 Enclosure Drill Template
SS-40 Photo Page
Front Panel Label
IF Filter Response Curve
Tuning Pot Kit For First run only.   Kits shipped after 25 June 2011 do not need the kit.

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