80 character display screenshots

Character displays offer a good, low cost option for TrxAVR-Picastar
Any 40x2 or 20x4 NT3881D display panel can be used, but we suggest the following:

These displays are bright with high contrast and a good size. (the 20x4 is 99 x 61mm)

This page shows images of my 40x2 Optrex display (ie: Ian, G3VPX).
These images plus the brief comments plus the Picastar manual should provide enough information to drive a transceiver
using these displays.

The layout is such that no item crosses the centre line. This allows a simple switch to convert the display to 20x4.
The Right half becomes the top two lines and the left half becomes the bottom two lines.

NT3881 displays have eight user definable characters. Six of these are used in the S meter display below.
They are half and full S meter bars and 10, 20, 30and 40 dB over S9.
The remaining two are 25w and 130w power meter calibration labels.
(So you only have a scale calibration numerics for ranges of 25w and 130w !!)
- but this is fine for Forward and Reflected with a 100w PA .)


Initial 'home' display on receive.
The left side is mainly S meter + DSP parameter set colour + IP/NF (for best IP3 / best NF)
The right side is the two VFO frequencies, switch states and mode (LSB, USB, CWL, CWU)
The filter switch indiation is <W> or >N< on SSB and CTX andDEP on CW. (Context and Depth... see Picastar manual)

VFO A is on the left and VFO B on the right.
Within a 20 character width, there is space for two 8 digit frequency displays + VFO A/B labels + spaces.
However, there is no easy way of indicating which is the current VFO.
So we only label the current VFO. Hence in the display above: A is current.


Transmit display showing forward power with 130w range.


Transmit display showing reflected power with a 25w range


Transmit display showing SWR

They are soft key tasks for Forward, Reflected, SWR and Toggle Fwd/Ref/SWR
See TrxAVR keypads


DSP switches showing Noise reduction and speech Compression on.
The letters nabamcv represent switches: Noise reduction, noise Blanker, Auto-notch, Manual-notch, Vox/qsk and Compression
If they are upper case then the switch is on.
<W> indicates that the filter switch is in the Wide position.


CW mode. Filter switch = Depth, mode = CW LSB


DSP parameter setting. Parameter 6.1 is currently 2.10kHz
DSP parameter setting is accessed from the 'home' state either by:

  1. Key 8, as in Picastar. The most recently adjusted parameter is displayed with its value.
    Parameter navigation uses the keypad as in Picastar
    ( see Picastar manual).
    Rotating the Menu Encoder can also be used for parameter navigation and will move
    through all the available parameters ( the list excludes those parameters fixed
    in September 2008 by G3XJP which are prefixed with an 'x' in USER2b2.XJP)
    The tuning encoder is used to change the value of the selected parameter.
     Key # or ESC to exit.
  2. Rotating the Menu Encoder by 1 click will display the most recently adjusted parameter as
    above. Keypad or menu encoder may be then used to navigate the parameter list..


DSP parameter setting on transmit. Parameter 8.1 Tx Drive

AF gain being adjusted by turning Potentiometer B
Here, DSP parameter 2.1, AF gain has been assigned to one of the optional front panel potentiometers.
The AF gain 95 display appears as soon as pot is moved and persists two seconds after no further movement.


SSB width narrow being adjusted by a rotary Encoder.
SSB width narrow (parameter 6.1) has been assigned to an encoder.
The first click of the encoder displays the message window showing current parameter value.
Subsequent clicks adjust the value. The value indication changes on each click.
The message window disappears 2 seconds after no further encoder activity, but if another encoder
is turned, the message switches to it immediately.


RIT mode - split on - see Picastar manual. (The s of RITs means split is on)
Refer to the Picastar manual for use of the # key in controlling RIT/XIT.
Note that the VFOs are now labelled r and t instead of A and B.

RIT mode- split off. VFOs revert to A/B labelling.


XIT mode - split is on. Refer to the Picastar manual for use of the # key in controlling RIT/XIT.
Note that the VFOs are now labelled r and t instead of A and B.


XIT mode - split is on, # key pressed to display transmit frequency difference.
# key behaviour is exactly as Picastar - except that if you hold
the # key, the transmit display changes immediately to frequency difference. (In Picastar, this only
happens when you tune. Such a restriction is unnecessary here as we have two VFO displays)


DDS commands - Long key 2 press
This functions as in Picastar. TrxAVR is now waiting for the second digit to complete the DDS command.
(see Picastar manual and DDS command list)


DDS command confirmation. Some DDS commands give a confirmation message that persists less than 2 seconds.
Here, DDS51 has been keyed (or a soft key assigned to green params)


DDS command confirmation - DDS48


Menu key pressed - first item is Encoders and Pots assignment.
Rotate Menu Encoder for rest of main configuration menu - or press Menu again to select.


Menu key pressed again - we are now in a list of 8 encoders and 2 pots which can be accessed by rotating the Menu Encoder


Menu key pressed again - we are now able to select a DSP parameter to assign to Encoder 1.
The menu key rotates through the list of DSP parameters. We press Menu to select and then ESC ESC to back out of the menu system.


Main menu item: Rx button assignment. This menu item assigns one of 50 or so DDS, DSP and other tasks to soft keys A to O.

Menu pressed - We are now in a list of 15 soft keys A to O which we can view by rotating the Menu Emcoder.
SSB Mode (ie DDS11) has been previously assigned to soft key A.


Menu pressed again - we are now in the list of 50 available soft key tasks.
Rotate the Menu Encoder to select a task and then press Menu to assign it to soft key A. Then ESC ESC to exit the menu system.


Main menu item to control the display's bright level (ie the level when it isn't dimmed!!) (We are in a list of Main menu items)


Menu key pressed. Bright level setting. Rotate the Tuning Encoder to set the level and then key Menu to confirm.
(The display brightness will change during setting)


Setting DDS clock frequency - Main Menu option.
You can also set this with DDS33 as in Picastar. See Picastar manual. DDDS33 uses signal generator mode.
This Main Menu facility does not use signal generator mode and so allows you to fine tune the calibration by tuning the receiver to a
signal of accurately known frequency.


Main menu setting of USB offset. This does use signal generator mode and so is the same as DDS 31. (See Picastar manual)


Guard channel monitoring. DDS55 keyed.  When the other VFO is being checked (2 seconds in 20) it is labelled G.


Memory stack scanning. DDS 56 keyed.  Scan interval shown: t=5s.   03 means Memstack 60   currently on slot 3.


Wobbulator mode. DDS 58 keyed.  From A to B.   scan rate shown. = 0.8kHz/sec.
Scan rate is set by the tuning encoder as in Picastar. The range of available scan rates was chosen by observing a classic Picastar.


VFO stack tuning mode. DDS27 keyed.    See Picastar manual. St = a sticky slot  (Vo for volatile)

Memory stack tuning mode. DDS60 keyed.     03 - stack 0 (60) slot 3

Rate tuning mode. DDS22 keyed.   Current rate is 0.8kHz/sec.

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