DESCRIPTION - The ECP-1 Preamplifier by Lance Johnson Engineering is a Low Band Receive Only Remote Preamplifier System for the 40-80 and 160 Meter Bands. This system was developed in 1997 by a Certified Professional Engineer and has been critically reviewed in the April 1998, Low Band Monitor, after two years of Beta testing by Colorado low band enthusiasts. Today, the ECP-1 system has been used successfully in over a dozen DXCC countries worldwide.
The basic (50 Ohm) ECP-1 Preamplifier System is made up of FOUR components:
1. Power Signal Box - A Powder Coated (HRO-60 Grey) Die Cast Metal Power Signal Box that is used in the Hamshack to distribute 12 Volt DC to the Preamplifier and RF to the Remote Receiver Input.
2. Preamplifier - The Elbert County Preamplifier is housed in a Powder Coated (HRO-60 Grey) Die Cast Metal enclosure, rejects BC Interference by as much as -40 db, matches (1:1) any Receiving Antenna with 50 ohm impedance and provides 10 db signal gain. By adding an accessory Beverage Box (9:1) Transformer or Pennant Box (18:1) Transformer the ECP-1 will work with these popular antennas.
3. Termination - The F/B 1000 is a Termination Device used to improve the Front-To-Back performance of your Receive Antenna. Detailed Set Up Instructions are Included!
4. The 12 VOLT DC (200 ma) Power Supply is now included with the ECP-1 System.
Try the ECP-1 System for 30 Days and if not satisfied simply return it for a full refund.
PRICE INCLUDES SHIPPING IN U.S.A - VISA and MasterCard Accepted!
FOR LOOPS:
The complete ECP-1 (1:1) System is only $99.95 with the Priority Mail Postage Paid.
Select your high quality matching transformers below:
PENNANT TRANSFORMERS and BEVERAGE TRANSFORMERS:
Accessory PB-1 (18:1) and BB-1 (9:1) Transformers for use with the ECP-1 (1:1) System or other Preamplifiers ar available.
Both the PENNANT BOX and BEVERAGE BOX Transformers are housed in a Powder Coated (HRO Grey) Diecast Enclosures that connects to the ECP-1 Prteamplifier.
Simply connect the PENNANT BOX or BEVERAGE BOX to the ECP-1 (1:1) with 50 Ohm Coax.
The complete PB-1 "Pennant Box" is only $39.95 with the Priority Mail Postage Paid.
The complete BB-1 "Beverage Box" is only $39.95 with the Priority Mail Postage Paid.
Both of these Transformers include Termination (453 Ohm or 910 Ohm) Resistors.
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THEORY OF OPERATION - The Lance Johnson Engineering ECP-1 Elbert County Preamplifier is a Low Complexity Amplifier for use with a Low Band (40-80-160 meter) Receiving Antenna whose impedance is 50 ohms (Coaxial Loop). Using accessory 450 ohms (Beverage) or 900 ohm (Pennant). Transformers above the ECP-1 will match these popular antennas,
The ECP-1 Elbert County Preamplifier is intended to be installed remotely at the feed point of the Receive Antenna for superior performance..
The signal and the filter direct current voltage is conveyed via the 50 ohm coax to the amplifier by the unit's high quality Power Signal Box.
The receiving antenna is connected to the external accessory PP-1 or BB-1 transmission line type toroid transformer.
The 50 ohm output connects to a High Pass Filter whose characteristics attenuate local AM Broadcast Stations, but pass signals with low insertion loss above 1.8 mz.
The High Pass Filter passes the desired RF signal to a rugged transistor amplifier.
The amplifier circuit was selected because of some unique design features.
This amplifier circuit uses two different types of feedback.
Both Shunt Feedback at (R1) and Emitter Degeneration at (R4 & R6) are deployed.
ATTRIBUTES - By proper selection of the values of these resistors, several valuable attributes can be obtained.
· Broad Band Frequency Operation.
· Control the input Z (50 ohm) to properly terminate the High Pass Filter.
· Allows the optimization of the Gain by varying the value of Resistor R4-6.
Transistor Q1 is a 2N2222A High Frequency Transistor with a Low N.F. is operated in Class "A" Mode.
When running Open Loop (w/o feedback) Gains in the region of 30 db can be obtained.
This much Gain would produce too much noise when used with a Receiving Antenna.
STABILITY - By using Shunt Feedback and Emitter Degeneration, the Gain can be adjusted to lower values that work well with Receive Antenna applications.
Shunt Feedback also enhances the Amplifier Circuit, making it unconditionally stable.
Shunt Feedback also decreases the output impedance, that allows the circuits Impedance Matching Transformer T2 to adequately match the 50 ohm output to the coaxial transmission line, via Capacitor C8.
The Direct Current Voltage is conveyed from the Power Signal Box via the coax to Inductor L4 and the Voltage Regulator (78LO8A) Regulator to maintain a constant 8.0 volts for Transistor Q1, independent of the length of the coaxial cable used.
GAIN - The 10 db. Gain of the Elbert County Preamplifier has been set to provide excellent performance on the 40-80 and 160 meter amateur bands.
POWER SUPPLY - The Power Supply supplied with the Power Signal Box is 12VDC with a 200 ma. rating.
CABLES - Cabling is simple. Cable needs will vary for the Remote Antenna Input from the Power Signal Box. The owner must understand the use of his Transceiver's Remote Receive Antenna Input to use the product.
Care must be taken when connecting the unit's Signal Input (RCA Jack on the Power Signal Box) to the Transceiver.
If the DC-Input connector (UHF Connector) is accidentally connected to the Receive Antenna Input, a DC Voltage on the Antenna Terminal could damage the transceiver.
WARNING - The Elbert County Preamplifier is a Receive Only device. If you transmit directly into the Signal Power Box, serious damage to the product will result. Lance Johnson Engineering does not recommend using the ECP-1 on transceivers that are not equipped with Remote Antenna Input.