Orion 565 V2, What's New!
In Version 2.059d
Updated September 7, 2006
Modified AGC system. Now has slow attack to eliminate hang-up on noise spikes.
A new AGC algorithm was created to reduce the effect of noise spikes
on the receiver's gain. Normally, the
receiver gain is adjusted instantaneously which allows the radio to
react to large signal increases without
overload. This is referred to as Fast-Attack AGC. The decay rate or
AGC gain recovery function on the
AGC is user programmable. The decay rate can be set from very fast to
very slow. A noise spike can affect
the AGC system just like a signal so spikes can cause a fast-attack/
slow-decay reaction in the AGC system.
To overcome this effect we have created a slow-attack AGC system that
provides the AGC system with
some significant immunity from noise spikes. So occasional noise
spikes will not cause the AGC system to
react and thus will not need to go through a slow-decay period.
New Speech Processor
Modified the Speech Processor to use envelope detection for gain
changes instead of peak-detection.
The speech processor algorithm was altered to replace the TX audio
peak-detector with an envelope
detector to facilitate instantaneous gain adjustments.
Added AGC Rise control the DSP and CPU code.
The new AGC system includes a new AGC slope feature that provides a
varying audio level in relation to
the received signal when the DSP AGC system is active. Stronger
signals will appear to be louder and weak
signals will appear to be weaker. The AGC Slope function can be
adjusted for OFF, 1dB slope or 2dB
slope. The 1 or 2 dB slopes refer to the amount of audio rise for
each 10dB of signal rise.
Lowered AGC Decay range to lower to 1 dB/S selection.
Longer AGC decay rates can be selected down to 1dB/S.
Added ALC LED Hang to provide better visual feedback of ALC action
It was found that the short duration of the Orion's ALC LED was being
interpreted as weak MIC gain
because the ALC led did not get brighter the more the deeper into ALC
the transmitter went. To make MIC
adjustment easier the duration of the ALC LED was increased for any
transmitter ALC reaction.
Increased SSB TX filter taps to improve the low frequency roll-off.
Sideband transmit filters have been made sharper to improve the
transmit low-frequency roll-off while
preserving opposite sideband rejection.
Added Keying Loop tracking to add support for previous form of the
keying system.
A new menu item has been added to the TX MENU to control the behavior
of the AMPKEY signal output
on the rear of the Orion. The user can select to have the AMPKEY
track the KEY LINES or track the
AMPKEY LOOP. In the first case, the AMPKEY output follows the key
line regardless off the state of the
keying loop (either open or closed). In the latter, the AMPKEY only
appears when the tx-loop is closed.
This new feature provides flexibility to external uses of the AMPKEY output.
Added additional Microphone Gain Control.
Additional gain control has been added to the microphone input path.
The new control is located in the SSB
menu and provides an additional 18 dB of gain on top of any existing
hardware or software MIC Gain
adjustment. This additional MIC Gain is provided by a previously
unused Programmable Gain Amplifier
(PGA) located in the microphone channel A/D converter. Care should be
exercised as the combined
Hardware Mic Gain, Software Mic Gain and the PGA can result in
distorted transmit audio caused by
excessive gain. Greater flexibility in the MIC Gain allows a wider
range of microphone types to be used.
See the Orion history file for fixes and patches contained in this release.
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