operation.txt

This document describes the operation of the RadioUno arduino radio controller. 
For the purposes of this document, it is assumed it is installed in and
controlling a radio. Please see the schematic for specifics.

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This controller has 4 push button switches. 3 Normal push buttons
and a 4th as part of the rotary encoder used to tune the frequency,
change channels and select items in the menu modes.

All buttons have more than one function. They are controlled by short presses
and long presses. A short press is defined as less than 1/3 of a second. A long
press is longer than that. In almost every case you will have some feedback 
(display change etc) with a button press.

Button 1 (vc): 
Short Press toggles between VFO and CHANNEL operation.

Long press when in VFO mode saves the displayed frequency and mode to the
memory channel displayed after VF (00 - 99) (STORE). 
Long press when in CHANNEL mode recalls the frequency and mode from the 
channel to the vfo and changes from CHANNEL mode back to VFO mode (RECALL).

Button 2 (mr):
Short press cycles thru the modes. These are:
LSB/USB/CW(usb)/CW(lsb)/WSPR/BECN

Long press toggles RIT on and off.

Button 3 (scq):
A short press initiates automated transmission (beacons).
When the mode is WSPR, a short press will send ONE sequence on the 
displayed frequency. A press will abort the WSPR transmission.

When the mode is CW, a short press will send: 
"CQ CQ CQ DE (your call) (your call) K"

When the mode is BECN, a short press will send a CW beacon on the
displayed frequency. A press will abort the CW beacon. 

A long press of the scq button will start the SCAN mode. This increments 
the displayed frequency in 200 hz steps for 100 khz. At this point is goes 
back to the original frequency and starts the scan again.

Pressing scq again stops the scan and puts the frequency back to the 
original. While in scan mode, pressing AND HOLDING button 1 (vc) will
pause the scan. Releasing the vc button resumes the scan.

Another control is the rotary encoder and included switch.
In VFO mode, turning this knob clockwise will increase the frequency
by STEPSIZE (default 10 hz). Turning counterclockwise decreases
the frequency by STEPSIZE.

A short press on the encoder switch increases the STEPSIZE to 100 hz.
Another push increases the STEPSIZE to 1 KHz. Another short press goes 
back to 10 hz.

A LONG press changes step size to 10 khz. Another LONG press changes STEPSIZE
to 100 khz. Further LONG presses toggle between 10 khz and 100 khz. 

A SHORT press changes STEPSIZE back to 10 hz. Each change in STEPSIZE will
place an underline cursor on the digit that is changed while tuning.

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The KEYLINE (active LOW) keys the transmitter. In SSB mode (USB/LSB) the transmit 
oscillator is set to the displayed frequency, and the keyline goes high. The "R"
on the upper right of the display changes to a "T" and the lower left of the 
display will show reflected power (assuming you wired up the analog lines
to a directional coupler). 
On release of the keyline the transmit oscillator is set to 1 mhz, the "T" on the display
changes back to "R", and the reflected power display changes back to MODE.

In CW mode, the same happens, but a sidetone is generated.

In WSPR and BECN modes, the keyline has no effect. These modes are initiated by the scq button.

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*** Before Connecting Power for the First Time ***

The DC voltage in line at pin A0 on the arduino connects to a variable
resistor that connects to DC power. The resistor needs to be set so that 
A0 reads 2.5 volts with +12.5 volts at the top of the resistor.

*** MAKE SURE THE A0 LINE NEVER SEES MORE THAN 5VDC.***
    (Or 3.3VDC if using a 3 volt arduino. I use a 5 VDC unit).
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*** When Programming the Arduino Controller ***

For the 3 beacon modes to work correctly, your CALLSIGN must be programmed
and the code run thru the compiler. Currently the Callsign defaults to D0MMY.

Look for the line #define CALLSIGN "D0MMY" just after the comments in the
beginning of the code. Your callsign MUST be entered in UPPER CASE.

The RFPOWER setting also needs to be changed. This is a number from 0 thru
43 that is the dBm power level of your transmitter. This is used for WSPR.

The GRID SQUARE is programmed from the MENU mode and is field changeable.
The grid square is saved in EEPROM. Your location may change. Power levels and
call signs typically do not.

There are 2 defines: MINFREQ and MAXFREQ. These set the lower and upper
frequency tuning limits and are set with the low pass filters your radio will be
using. Setting these is entirely up to you. 

Receive Frequency: I use a Tayloe detector. This requires the receive frequency
to be 4 times the displayed frequency. With the PLL setup values I use, the highest
DISPLAYED frequency is about 30 MHz. This is multiplied by 4 to 120 MHz. Any excursion
beyond this means you will need to play with the PLL values. 

If you use a DC receiver where the receive frequency is the same (+/-) as the 
displayed frequency, then you can set the MAXFREQ as high as about 150 MHz.

The MINFREQ should not go lower than about 200 KHz with the current PLL values.

If you use a superhet receiver, you will need to calculate the mixer oscillator
frequency based on your I.F.

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*** First Use ***

There are some values that MUST be configured the first time the controller is used.
To set these, go into the MENU. While holding the VFO/CHANNEL button, turn on
power. When 'Menu" comes up, release the button. Turn the rotary encoder to select
the various menu entries, and press VFO/CHANNEL to select the entry.


The first is "set defaults". Press the VFO/CHANNEL button until "writing" shows up.
Release the button. You will see the channels being programmed. Other default
values will also be loaded into EEPROM. When finished, you will go back to "set defaults".

Rotate the knob to select "Calibrate Osc". Press the VFO/CHANNEL button. You will
see "Rotate knob" and a 0. The 0 is the frequency offset and can be +/- the reference
frequency. Right now OSC 2 is putting out 10 mhz. Use a calibrated receiver or
frequency counter to detect this. Rotate the knob while testing the frequency at OSC 2.
When it is exactly 10 MHz press the VFO/CHANNEL button. This will save the value.

Two other menu options can be changed: "Sidetone" and "Set Grid Square". The sidetone
is also the receiver offset in the CW modes and defaults to 700 hz. This can be
left unchanged.

The default gridsquare is AB01 and can be changed at your convenience.

Power OFF the radio when done. Powering back on WITHOUT the VFO/CHAN button pressed 
starts normal operation.

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*** More Details ***


At power up, the frequency and mode are read from memory channel 00 in
EEPROM. These are used for initial operation. The channel number is then 
set to 01 and the radio is put in VFO mode.

The radio is put in receive mode and the band map register is set and
the band lines are output on the MCP23008 port expander to select the 
low pass filters.

The default tuning step is set to 10 hz. A line (the cursor) will appear under
the digit that will change when the rotary encoder is used to tune to 
another frequency. Pressing the button on the rotary encoder will change the
tuning speed. A short press will go from 10 hz to 100 hz to 1000 hz then back to
10 hz. A long press (> 300 msec) will toggle between 10 KHz and 100 KHz and
back to 10 KHz. A short press puts you back to 10 hz.

The LCD display will show the following:
Left, top line:
VF (vfo mode)
01 (the memory channel in CHANNEL mode is set for channel 01)
The transmit frequency (receive frequency will differ in certain modes)
A 'R' for receive. (This switches to 'T' in any transmit mode).

Left, bottom line:
The mode (LSB, USB, etc)
If active, 'RIT'.
DC Voltage read from the DC in line

If the VFO/CHANNEL button is pressed while TURNING ON the radio, you will 
placed in the MENU mode. Details about the MENU mode are discussed elsewhere.

Turning the TUNE knob will change the displayed (and RF) frequency. Clockwise
tunes UP, counter-clockwise tunes DOWN. 


A short press on the MODE button steps through the modulation modes. They are:
LSB (lower side band)
USB (upper side band)
CW-U (CW, upper side band receive)
CW-L (CW, lower side band receive)
WSPR (WSPR beacon)
BECN (CW beacon)
and then back to begining (LSB).

A short press on the VFO/CHANNEL button will toggle between VFO mode and 
CHANNEL mode. In VFO mode, you will tune between MINFREQ (set in the source 
code as 2.90 MHz) and MAXFREQ (set in source code as 15.2 MHz). (You can
change MINFREQ and MAXFREQ in code).

In CHANNEL mode you can select 100 channels from 00 thru 99. Each channel
holds a frequency and mode.

When in VFO mode, a short press goes to channel mode. The current frequency 
and mode are stored. A short press while in CHANNEL mode will restore the
saved frequency and mode and jump back to VFO mode.

In CHANNEL mode rotating the rotary encoder clockwise will increase the 
channel number by 1 until channel 99. Then further clockwise rotation will 
go back to channel 00. Rotating the rotary encoder in CHANNEL mode counter-
clockwise will decrease the channel number by 1 until channel 00. Further 
rotation past 00 will go to channel 99.

Pressing the encoder switch will increment the channel number by 10, going
back to 01 after channel 99.

When in CHANNEL mode, a long press of the VFO/CHAN button will recall the 
current channel information (frequency and mode) to the VFO, deleting whatever 
was in the VFO at the time. Also you will switch from CHANNEL mode to VFO mode 
when recalling a channel.

When in VFO mode, a long press of the VFO/CHANNEL button will store the current 
VFO frequency and mode to the channel number shown in the display. The current 
VFO frequency and mode will not change. You will see a displayed message that the 
data was stored showing the channel it was stored to.

If you want to store the current VFO data to a channel you are not on, do the
following:

Short press on VFO/CHANNEL button to select channel mode.
Rotate the rotary encoder to select the channel. 
Short press on VFO/CHANNEL button to go back to VFO mode.
Long press on VFO/CHANNEL button will store the displayed frequency and mode
to the displayed channel.

Note: you can tell the current channel by the 2 digit number after the VF on the display.



-- WSPR --

To use WSPR, either dial in one of the wspr frequencies on the VFO or go to preset 
channels 8-11. WSPR is time sensitive. It starts at 1 second  after the even numbered 
minutes. After selecting the frequency, short press the  MODE button to select WSPR. 

At 1 second past an even numbered minute, press the scq button.
A wspr transmission will start and continue for the next 110 seconds (appx).
If you want to abort the transmission, press the scq button. Otherwise the 
transmission will stop normally after about 110 seconds and return to receive mode.

Your call sign and power are encoded in the beginning of the source code, while
the grid is set from a menu entry. These will need to be set for WSPR to operate
correctly. See the notes above.

-- DC Voltage --

Before powering up this controller, make sure the variable resistor tied to port
A0 is set so that the voltage is set to 2.5 volts with 12.5 volts at the top of the
variable resistor.

The DC voltage is updated appx. every 5 seconds.

-- SWR Display --

Pin A3 is tied to a directional coupler to read reflected power during transmit.
The lower part of the LCD display will show a set of vertical bars corrosponding
to reflected power during transmit. The greater number of bars the greater the
reflected power. Note that this is a relative reading only.

-- Setting Default Channels --

Below the main code is a list of 100 channels and modes. These are used as default channels
when initializing the controller. These are overwritten when you store a channel in 
memory. These frequencies can be below MINFREQ (set in #defines) and above MAXFREQ.
This makes it useful for beacons where transmitting is all that matters. For this reason, 
if the channel frequency is greater than MAXFREQ, the receive oscillator is set to
1 mhz.

Pressing and holding the VFO/CHANNEL button during power on will enter the MENU mode.
Rotating the knob to 'set default chan'. Press the VFO/MEM button. You will see
'working' displayed. Release the VFO/CHAN button. The channel number will be displayed 
as each channel is loaded.

After a couple seconds, you will see 'done'. Power cycle the controller and channels 
00 thru 99 will be set to the frequencies and modes seen in the bottom of the source code. 
NOTE: This also reset the oscillator calibration to  0 hz and the sidetone frequency 
to 700 hz and set the grid square to AB01.

-- Calibrating the Oscillator --

Go into MENU mode (Press VFO/CHANNEL button while turning the radio on).
The first option is Calibrate Osc. Press the VFO/CHANNEL button. The current
frequency offset will be displayed (0 hz). Rotate the knob until the output at
OSC 2 is exactly 10.0 MHz. Press the VFO/CHANNEL button to set. Power cycle to 
resume normal operations.

-- Sidetone -- 

During CW transmit, sidetone is generated at pin A1. This is a square wave and should 
be fed to a low pass audio filter to make it sound better. Also the sidetone frequency 
is used as a cw offset in receive. You can change this. Power off the radio. Press and
hold the VFO/CHAN button while turning on to enter the MENU mode. Rotate the knob
until SIDETONE appears. Press the VFO/CHAN button. Now rotating the knob will change
the frequency of the sidetone (and cw offset) down to 500 hz and up to 1000 hz. The
sidetone will also be operational while adjusting. When you get the tone you want
press the VFO/CHAN button to save the value.

Power cycling the radio will go back to normal operation.

-- Setting the Grid Square --

The grid square is sent during WSPR and CW Beacon. This needs to set to your location.
Enter the Menu, select 'Set Grid Square'. The current grid square (saved in eeprom) will
be displayed. Use the encoder knob to select the letters/numbers of your grid square.
A push on the encoder switch will advance to the next position.
When the grid square is correct, press the VFO/CHAN button to save to eeprom.
If you do not want to save the new grid square, power off the radio. 

-- RIT --

Press and hold the MODE/RIT button (long press, > 300 msec). This enables the RIT
(Receive Incremental Tuning). The transmit frequency will stay fixed, but the receive
frequency will change. The default tuning speed is 10 hz, but pressing the tuning
knob will change the tune speed (see above). The VFO/CHAN and MODE functions are
disabled while in RIT mode, but you can tune to any frequency the radio allows
while in RIT mode. 

Pressing and holding the MODE/RIT button (longer than 300 ms) will turn off the RIT
mode and reset the receive frequency to what it was before selecting RIT.

-- SCAN --

There is a band scan feature. Press (long press) the scq (Scan/CQ) button to start the scan. 
The displayed frequency will step up 200 hz at a time thru 100 KHz. When the 
frequency + 100 KHz is reached, the frequency will jump  back to the starting point and 
resume scanning. This will repeat until the scq button is pressed again. Pressing the VFO/CHAN
button while scanning will pause the scan until the VFO/CHANNEL button is released.

This works in VFO mode as well as CHANNEL mode. This is useful in looking for 
activity on a dead band.

The default mode while scanning is USB.
 

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There are a lot of comments in the source code. If you are competent at all, you should
have no trouble making changes to suit your needs.