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NorthStar

Cherokee NightRider


WINScanner

WINScanner


NR-100 Block Diagram

NR-150 Block Diagram

NR-150 Wiring Diagram



Microphone Connection

Pin Description
1 Ground
2 Microphone
3 TX Key (Connect to Ground)
4 Speaker (Connect to Ground)

COMPONENTS

NS-100 Schematic Diagram

NS-150 Schematic Diagram

MC145106P PLL Frequency Synthesizer

TDA6130-5 TX Mixer

TA7310 Oscillator, Mixer and Amplifier

TA7222 Audio Power Amplifier

NJM4558 Dual Operational Amplifier

LM324N Quad Operational Amplifier

2SC1969 RF Finale Transistor

2SC1966 RF Driver Transistor


Improved receive gain

Quieting of AM reception and improving gain of incoming signals is a common request from radio operators. In the first stages of the HF input 2SC1674 transistor can be found. This transistor is responsible for the amplification of a small detected signals. A problems exist if the transistor itself is noisy as is such the case of the 2SC1674 when compared to other low noise packages. Along with the amplification of the incoming signals is transistor noise. Replacement of this transistor with a higher gain, lower noise transistor greatly improves the signal to noise ratio of your receiver.
We will use an 2SC2999 transistor that has higher gain lower noise characteristic. Replace the 2SC1674 (TR17) with an 2SC2999 (or similar low noise and high gain transistor) to achieve this improved signal to noise ratio.
Re-Adjust L5 and L6
The gain will improved with more than 6dB with the same signal to noise ratio.