The TEN-TEC RX 340 is a multi mode, general coverage synthesized receiver utilizing extensive Digital Signal Processing. DSP brings the performance and repeatability of expensive military grade communications receivers into the price range of top end commercial receivers for shortwave listeners. Tunable from 5 kHz to 30 MHz, it provides tuning steps and display resolution of 1 Hz. All three displays are blue green vacuum fluorescent and provide unparalleled contrast and readability. The RX 340 is a laboratory quality instrument in its ability to quantify the amplitude and frequency characteristics of signals and receivers.
The performance level of receivers in this class is possible only through extensive use of Digital Signal Processing. These designs utilize fewer analog circuits than traditional receivers. Powerful, specialized DSP microprocessors replace many of the discrete circuits with intensive software containing over 60,000 lines of code. High dynamic range analog stages provide 1st , 2nd and 3rd I.F.s and 80 dB of AGC where signals then pass through analog to digital converters. Everything else is accomplished in DSP including all mode detection, I.F. filters, AGC remaining 40 dB , adjustable BFO , passband tuning and noise blanker. An astounding 57 I.F. bandwidths from 100 Hz to 16 kHz are included. All filters have shape factor of 1.5 1 or better 6 to 60 dB . USB , LSB , ISB , CW, AM, Synchronous AM and FM are built in. Four AGC modes are provided. Conventional Fast, Medium and Slow modes are familiar but the Programmable mode is groundbreaking. User may build their own personal AGC characteristic by selecting attack, hang and decay rates. Manual control from front panel is also adjustable over 120 dB range. A tunable notch filter rejects unwanted signals in the passband. Receiver front end incorporates built in preselector with eight octave bandpass filters. Switchable 10 dB preamp and 15 dB attenuator are also provided. Signal strength meter is calibrated in both’s sunits and dBm.
TEN-TEC has been supplier of commercial government grade receivers for some years now. Our RX 331 was previously available only in a black box version for remote control. That model is used in government military applications worldwide where multiple units run 24 hours 7 days a week without interruption. RX 340 uses these field proven circuits the PC boards are identical brought together in a new cabinet with a comprehensive front panel. This provides conventional operation from the panel while retaining all of the remote control aspects of its predecessor. A built in multi drop RS 232 interface permits remote operation at baud rates from 75 to 38,400. Accessed from rear panel DB 25 connector, the interface can be configured for single or multiple receiver applications. The complete command language is published in the manual so enterprising users can write their own remote control software. RX 340 also includes Built in Test or BITE . This self test capability will identify virtually all faults to the board level.
Memory and scan features fall into four categories a scratchpad memory, 100 memory channels, memory scan and F1 to F2 scan. Each memory channel retains the frequency along with mode, I.F. bandwidth and BFO setting. Dwell time is programmable, Channel lockouts are provided and a pause feature lets you interrupt scan momentarily. Squelch works in all modes and adjusts over a 150 dB range.
RX 340 has built in TCVCXO to provide 1 ppm frequency stability across the entire operating range of 0 to 50 degrees C. Audio is delivered to built in speaker on the top panel, external speaker jack on rear and front panel headphone jack. Separate volume controls provided for speaker and headphone. Fixed level 600 ohm audio is also provided on rear panel. Front panel is a Lexan graphics overlay designed to last a lifetime. Chassis is aluminum with alodine plating on all parts to protect finish in less than ideal environments. Measuring 5.25 x19 x12.5 HWD , RX 340 can be mounted in a standard 19 opening rack and weighs 12.5 lbs. One year warranty. Made in U.S.A.
RX 340 was recently endorsed by noted receiver design engineer, Dr. Ulrich L. Rohde, KA2WEU:
“In testing the RX 340, I find that this is the only affordable, totally DSP based receiver where the digital AGC is as good, if not better than analog AGC systems. The intercept point for reasonable spacing is very impressive, better than +35 dBm in all cases.
WorldStation, a sophisticated software package to operate the RX 340 under computer control, is now available from DXT ra, Inc. Click here to access the DXT ra website at www.dxtra.com DXT ra, Inc. is a TEN-TEC authorized value added reseller of TEN-TEC receiver products.