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SAGE-300 Installation

Speech Audio Gain Equalizer

1. Preparation
1. Remove the Circuit Board from the Packaging and inspect it for damage.
2. If you are not already, familiarize yourself with the schematic and operation of the receiver you are planning to install the SAGE-300 into. This is a key step, as the SAGE-300 must be calibrated to your specific Receiver/application to ensure optimal operation.
2. Tools Needed
1. #1 flat blade screw driver or alignment tool
2. Fine Tipped soldering Iron
3. Electronics Grade solder
3. Additional Materials
1. 22~26AWG wire optional (if cable provided is not used).
2. Double Sided Tape (provided) or #2 machine screws and nylon standoff’s
4. Pre-requisites
1. Full understanding of your Receivers Operation and Audio Path (s).
2. Test Equipment (or a good ear).
1. Audio Tone Generator
2. Basic Audio Grade Oscilloscope
3. Transmitter capable of transmitting on the target receivers frequency
5. Specifications
1. Voltage Range: 10~18 VDC (12 Vdc Nominal)
2. Current Drain: 10ma typical
3. Input Impedance: 10K ohms AC coupled.
4. Output Impedance: 150 ohms AC coupled.
5. Gain +/- 10dB
6. Frequency Response: 275Hz to 4.4kHz controls set to center position (3dB down points).
7. THD: Less than .1%
8. Input Range: 0 to 8 volts Peak to Peak with controls set to center position/supply voltage at 12vdc.
9. Dimensions: 2.3" wide. 1.5" deep. ½" tall.
10. Mounting: Double sided tape (Provided) or via #2 screw holes.
6. Installation
1. Typically the SAGE-300 is installed between the audio output of a receiver and the modulation circuits of your transmitter. Note: If used with a repeater controller that decodes CTCSS tones the Sage-300 should be installed after to the point where the CTCSS is sampled. Typically this would be at the output of the Repeater Controller (to the transmitters modulation circuits).

Supply Voltage

2. Attach the Supply voltage (10~18Vdc) to either P1 Pins 1 and 2 (6 pin header) or to P-2 Pins 1 and 2. The supply voltage should be fused or protected against shorts. If a voltage internal to your transmitter is used please confirm that it has capacity to support the additional load.

Audio Input

3. Attach the Audio Input to P1 pins 6 and 5 (6-pin header) or P4 pins 2 and 1. It is recommended that you use shielded audio cable if the connection is longer than 6 inches in length or the SAGE-300 is used in a high RF environment. Typically the wire provided will work well.
4. Be sure to have a good ground at both ends of the audio path.

Audio Output

5. Connect the Audio to your transmitters modulation circuits to P1 Pins 4 and 3 (6-pin header) or P3 pins 1 and 2. Again it is suggested that you use shielded audio cable for long connection or high RF environments.
6. Be sure to have a good ground at both ends of the audio path.

Mount the SAGE-300

7. Utilizing the double sided tape provide or 2 each number 2 screws and nylon standoffs attach the DSL to a permanent location of your choosing. Be sure to confirm that you have not mounted it too close to a heat source or in a location where the board may be shorted out or damaged by other components, parts or wires.

Calibration

8. Ensure the output of your receiver does not exceed 4 volts peak to peak with a fully modulated signal at its input. If this is the case it will be required that you reduce this level to limit distortion and ensure proper operations.
9. Set all 3 Band Segment adjustment to nominal (screw slots vertical or straight up and down).
10. Test Equipment Method of Calibration
1. Using a Transmitter of known audio quality.
1. Attach an audio generator to the audio input of the transmitter (be sure not to exceed the manufactures specified input levels).
2. Tune the Transmitter to the Receivers frequency.
3. Attach the Audio Generator to the Transmitters Audio input.
4. Generate the desired audio frequency (typically start with the low band segment)
5. Enable the transmitter’s PTT circuitry.
6. Attach an Oscilloscope to the output of the SAGE-300 (P1-4 or P3-1) and observe the audio level of the transmitted signal. With the Band Segment adjustment at center position the gain should be nominal (no gain). Adjust the observed signal as you adjust the Gain to achieve the desired increase/decrease.
7. Repeat Steps 6.10.1.1 through 6.10.1.6 until all Audio Frequencies of Interest are adjusted to the desired levels for each of the band segments (low/mid/high).
2. Listening Method of Calibration
1. Utilizing off the air conversations or normal audio activities vary the 3 Band Segment adjustments until the Audio Quality sounds best to you. (Keep in mind that you can overdrive the SAGE-300’s input causing distortion of the output signal. Be sure you start your Calibration from the Center Position of each of the Band Segment Adjustments).

K2RF will also repair the SAGE-300 out of the warranty period for a nominal cost.