Friday, March 27, 2015

End Fed Half Wave Antenna

I have found the End Fed Half Wave (EFHW) antenna to be the best all-around solution for portable operation. It is easy to deploy, requiring a single point of support.  If a support is not available I use the 31 ft Jackite fiberglass pole and a drive-on mount or alternatively dropped over a driven T-post.  These are truck camping alternatives only!  The hardware and tools are large and HEAVY but easy to use.

I have tried many of the well documented and the black-magic couplers and find little difference in performance.  I usually default to the coupler promoted by EARCHI (http://www.earchi.org/).  It is easy to build, or you can support the club by purchasing it assembled.

EARCHI EFHW Coupler

In all cases a tuner is REQUIRED.  I use only Elecraft tuners, either internal to the rig or the T1 external tuner. I use RG174 coax exclusively and favor N-Type connectors, primarily for ease of assembly. If the coax is 25 ft or longer I have found that additional counterpoise is NOT required. I have used a Common Mode Current Choke near the operating position but have not identified any significant benefit at QRP power levels.  Fourteen turns of RG174 on 3 inch PVC provides approximately 1K Ohms at 7.040 mHz.  Simply drill 1/2 inch holes at each end of a 3 inch section of 3 inch PVC.  Carry this and a handful of tie wraps.  If you suspect RF on the feedline, simply wind the choke (without cutting the coax) and secure it with the tie wraps.

How to Use the KDSP2 DSP Filter

ELECRAFT® K2 160-10 Meter SSB/CW Transceiver

Revision B, March 3, 2015


The KDSP2 is controlled by the following keys:
STORE  RCL   AFIL  AGC  XFIL  DISPLAY  BAND+  BAND-
When a button is to be momentarily pressed (tapped) it is shown like this:
BAND+
When a button is to be pressed and held for ½ a second, and then released, it is shown like this:
STORE.
The KDSP2 recognizes three modes:
C for CW;
S for SSB (it does not distinguish between LSB and USB);
r for RTTY.
For each mode, the KDSP2 maintains four filters.
Filters for the current mode are selected by holding the AFIL button.
Each time you hold and then release the AFIL button, you cycle to the next of the four filters in the current mode.
Filter Status Display
The K2 provides a filter status display, invoked by holding AFIL + AGC.  This displays the current XFIL and AFIL settings. For example, in CW mode, you might see
FL2 0.7 c
followed by
AF 1
The first display shows the DSP filter in use (#2 in this example) and the current XFIL width (700 Hz in this example) and the mode (c for CW in this example).  The second display is Audio Filter and number.  This display does not distinguish between modes, showing the DSP filter as AF rather than CF, SF, or RF.
NOTE: If AFIL has not been held since powering on the K2, only the XFIL information will be displayed.  The AF value reflects the last mode in which you held AFIL.
KDSP2 Primary Menu Displays
Each mode has its own primary menu display.  After you select a DSP filter for the current mode by holding the AFIL button, the mode and filter number momentarily appear in the K2 display.  To display the primary menu for the current mode, tap the DISPLAY button.
The typical SSB mode primary menu:
S2 nr nt
where S is SSB, 2 is filter #2, nr is de-noiser state, and nt is notch filter state.
The typical CW mode primary menu:
C2 nr
where C is the normal CW filter, 2 is filter #2 and nr is de-noiser state, or:
c2 nr
where c is the “soft” CW filter, 2 is filter #2 and nr is de-noiser state.
The CW normal filter and the CW soft filters are toggled by tapping BAND-.
The SSB and CW modes primary menus are used to enable/disable the notch filter and noise reduction (de-noiser) functions.
When the de-noiser or the notch filter is enabled, the corresponding symbol is prefixed with a period.
S2 .nr .nt
C2 .nr
The de-noiser state is toggled On and OFF by tapping BAND+.  When the de-noiser is toggled from OFF to ON a display similar to one of these will appear for a second:
S2 .n2 nt
C1 .n2
In each instance the r (of nr) is replaced by the current noise reduction level.
You may cycle through the levels of the de-noiser by holding and the releasing STORE.   The de-noiser levels for SSB and CW are set independently.  When ON, the noise reduction function is active for ALL four filter selections of the CURRENT mode.  If OFF, the KDSP2 automatically enables noise reduction whenever an adjustment is made.
The notch filter state (available ONLY in SSB) is toggled On and OFF by tapping BAND-.
In RTTY, neither the notch filter nor the noise reduction (de-noiser) function is available.  Therefor the primary menu for RTTY is the Filter Menu explained below.
KDSP2 Filter Menu Displays
In all modes, DSP sub-menus are accessed from the primary menu, in sequence, by holding  and then releasing RCL.  In other words, when a DSP primary or sub-menu is displayed, the next DSP menu in the current mode’s sequence is accessed by holding and releasing RCL.  The sequence wraps back to the beginning when RCL is held and released on the last sub-menu.
IMPORTANT: If the KDSP2 is bypassed (dSP byP) your only menu navigation options are tapping  BAND+ to re-enable the filter or tapping XFIL to exit the KDSP2 menu and return to normal operation.
CW Menu Sequences
CW Menu Sequence
Typical
Remarks
Primary
C1 nr

Filter
C1 1.3 .65

DSP Bypass
dSP On
Hold STORE to return to primary menu
DSP Bypass
dSP byP
Tap BAND+   to turn dsP ON, or
tap XFIL  to exit KDSP2 menu
Noise Reduction
Nr 89 71

CW Noise Reduction GAIN
Cn G 0.0
Hold STORE to view firmware revisions
CW Filter GAIN
CF G 0.5
Hold STORE to view firmware revisions

SSB Menu Sequences
SSB Menu Sequence
Typical
Remarks
Primary
S2 nr nt

Filter
S.2 .20 2.5

DSP Bypass
dSP On
Hold STORE to return to primary menu
DSP Bypass
dSP byP
Tap BAND+   to turn dsP ON, or
tap XFIL  to exit KDSP2 menu
Noise Reduction
nr 89 81

Notch Filter
nt 40 .07

SSB Noise Reduction GAIN
Sn G 7.0
Hold STORE to view firmware revisions
SSB Filter GAIN
SF G 0.0
Hold STORE to view firmware revisions

RTTY Menu Sequences
RTTY Menu Sequence
Typical
Remarks
Filter
r2 2.5 1.0

DSP Bypass
dSP On
Hold STORE to return to primary menu
DSP Bypass
dSP byP
Tap BAND+   to turn dsP ON, or
tap XFIL  to exit KDSP2 menu
RTTY Filter Gain
rF G 0.0
Hold STORE to view firmware revisions

In SSB mode, a typical filter menu display might be:
S.2. .20 2.5
This shows the mode (S), filter number (2), lower cutoff frequency (.20 kHz) and upper cutoff frequency (2.5 kHz).  The decimal point after the S in S2 indicates the de-noiser is active. The decimal point after the 2 in S2 indicates the notch filter is active.
If a CW or RTTY filter were being displayed, the numbers represent center frequency and width:
C.2 .60 .80
This example shows the standard CW filter number 2, de-noiser active, .60 kHz center frequency and .80 kHz width.  (The notch filter is NOT available for the CW mode.)
A blinking decimal point prefix indicates which parameter value may be changed by tapping the BAND+ or BAND- buttons.
To change which parameter will be edited,, hold the STORE button. The blinking decimal point will move to the other parameter.
Saving KDSP2 Filter Settings
Every time you make a change to any KDSP2 setting, it is automatically saved into EEPROM.
Bypassing the KDSP2
If you switch to the KDSP2 menu while the DSP is in bypass mode you will be sent directly to this menu.
If the KDSP2 is bypassed (dsp byP) you have only two options.  Tap BAND+ to re-enable the KDSP2.  Tap XFIL to exit the menu and return to normal operation.
If the KDSP2 is not currently bypassed, to access the Bypass Menu hold and release RCL repeatedly until dsp 0n is displayed.
Tap BAND- to bypass the DSP.  The display will show:
dsp byP
Tap BAND+ to re-enable the DSP.  While the DSP is synchronizing with the current mode of the K2, the display will show something like this:
d2 .nr nt
When the synchronization is complete the d will be replace by the letter indicating the current mode.
If you wish to exit the menu system leaving the KDSP2 bypassed, tap XFIL.
From the Bypass menu, if the KDSP2 is enabled (dsp 0n), you can hold the STORE button to return to the primary menu for the current mode.  If you hold the RCL button, you will be taken to the next sub-menu of the current mode.
De-noiser Menus
Hold and release RCL until the De-noiser Menu is displayed:
nr 89 71
The characters nr indicates the de-noiser, or noise reduction, menu. The first number indicates the Beta, or aggressiveness, of the filter and the second number affects the hold time, or decay rate of the filter. The values 89 71 shown are the factory default.
A blinking decimal point prefix indicates which parameter value may be changed by tapping the BAND+ or BAND- buttons.
To change which parameter will be edited,, hold the STORE button. The blinking decimal point will move to the other parameter.
Low Pass Filter
The low pass filter (LPASS) filter has a width in CW mode from a few tens of Hertz to 2.5 kHz; in SSB mode to 3.0 kHz; in RTTY mode to 3.5 kHz.
In CW and RTTY modes, to invoke the low pass filter, increase center frequency to its highest value and bandwidth to its widest value.  You will then see:
C.1 LPASS if mode is CW, filter is #1, and the de-noiser is enabled, or
 C1 LPASS if mode is CW, filter is #1, and the de-noiser is disabled.
In SSB mode, to invoke the low pass filter, increase the high cut off frequency to its maximum limit (3.0 kHz) and reduce the low cut off to its minimum (.00 kHz).  You will then see:
S.2 LPASS if filter is #2 and the de-noiser is enabled, or
 S2 LPASS if filter is #2 and de-noiser is disabled.
To change from this special filter, just tap BAND- or BAND+ to move the last edited parameter from its extreme.
Notch Filter Menu
Hold and release RCL until you see the notch filter menu (nt):
nt 39 07
This is the notch filter menu.  The first parameter represents Beta and the second parameter Decay.  The value shown is the factory default.
A blinking decimal point prefix indicates which parameter value may be changed by tapping the BAND+ or BAND- buttons.
To change which parameter will be edited, hold the STORE button. The blinking decimal point will move to the other parameter.
Gain Menus
Hold and release RCL until you see the GAIN menu of interest.
Of the five Gain Menus available in the KDSP2, three are based on mode (CW, SSB or RTTY) and two are related to the de-noiser function.
The SSB de-noiser Gain menu looks like this:
Sn G 7.0
The CW de-noiser menu looks like this:
Cn G 0.0
The Filter Gain menus are prefixed:
CF G 0.0 for CW Filter
Sf G 0.0  for SSB Filter
rF G 0.0  for RTTY Filter
The numeric parameters indicate the gain setting in dB. The setting may be changed in 0.5 dB steps, from ‑5.5 to +18.0.
To increase the setting, tap the BAND+ button. To decrease it, tap the BAND- button.
Displaying KDSP2 Firmware Revision
In order to view the firmware revisions you MUST be in any of the five GAIN menus.  Hold the STORE button.  You will see the firmware revisions of the DSP and KDSP2 controller.  For example:
dSP 03.16
which indicates the DSP Flash firmware version is 3.16, followed two seconds later by:
CtL 03.00
which indicates the controller firmware version is 3.00.
Real-Time Clock Menus and Displays
From any DSP menu, you may enter the clock menus by holding STORE + RCL.  You should see the current time displayed in standard 24-hour format:
14.11.07
If you see
  -----   
you were not in a DSP menu when you held STORE + RCL.
If the voltage of the Lithium backup cell is below limits, the time and calendar displays will be filled with E.
EE.EE.EE  or  EE-EE-EE
After replacing the battery, follow the clock and calendar setting procedure.
If you have replaced the battery correctly and see EE.EE.EE or illegal characters/symbols, proceed with the clock and calendar setting procedure.
To display the date for two seconds, from the time of day display, tap either BAND button.  You will see the current date as:
04-22-03 (MM-DD-YY) or 22-04-03 (DD-MM-YY)
Holding STORE will return you to the primary DSP menu of the current mode.
Selecting the Date Format
From any DSP menu, enter the clock mode by holding STORE + RCL.  You will see the current time of day in 24-hour format:
14.11.07
Hold RCL.  You will see the current date format as:
nn-dd-yy or dd-nn-yy
Tap either BAND button to toggle between these formats.  When you have made your selection, hold STORE to save it to EEPROM.  The calendar will be displayed for two seconds, and then the display will return to time of day.
Setting the Real-Time Clock
From any DSP menu, enter the clock mode by holding STORE + RCL.  You will see the current time of day in 24-hour format:
14.11.07
Hold RCL.  You will see the current calendar format as:
nn-dd-yy or dd-nn-yy
From this, the calendar format view, hold RCL to enter the real-time clock setting routine.
You will now have the opportunity to view and change (f desired) the following values:
Field Name
Typical Display
Year
yr 03
Month
m 04
Day
dt 22
Hour
Hr 14
Minute
m 11
In each of the menus the parameter may be changed by tapping BAND+ to increase its value or tapping BAND- to decrease its value.  Each of the parameters will wrap when their value reaches the maxima or minima.  The firmware allows you to enter an invalid day of the month.  The clock hardware will correct the errors when it advances to the next day.
Hold RCL to save the current value and move to the next.  You may return to the time display at any time by holding STORE.  Holding RCL while on the minute menu will also return you to the time display.
Each time BAND+ or BAND- is tapped, seconds are set to zero.  This provides a convenient way in which to synchronize with an accurate time source such as WWV.

Factory Default CW Filter Settings
Filter
Center
Width
Notch
Denoise
Denoise Level
1
LOW PASS
LOW PASS
Not avail
Off
1
2
600 Hz
800 Hz
Not avail
Off
1
3
600 Hz
250 Hz
Not avail
Off
1
4
600 Hz
100 Hz
Not avail
Off
1

Factory Default SSB Filter Settings
Filter
Low Cutoff
High Cutoff
Notch
Denoise
Denoise Level
1
LOW PASS
LOW PASS
Off
Off
1
2
200 Hz
2.5 kHz
Off
Off
1
3
300 Hz
1.9 kHz
Off
Off
1
4
300 Hz
1.6 kHz
Off
Off
1

Factory Default RTTY Filter Settings
Filter
Center
Width
Notch
Denoise
Denoise Level
1
LOW PASS
LOW PASS
Not avail
Not avail
Not avail
2
2.5 kHz
1000 Hz
Not avail
Not avail
Not avail
3
2.2 kHz
300 Hz
Not avail
Not avail
Not avail
4
1.0 kHz
200 Hz
Not avail
Not avail
Not avail

Other Factory Defaults
de-noiser
Beta
89

Decay
71

SSB Gain
7.0 dB

CW Gain
0.0 dB
notch filter
Beta
40

Decay
07
SSB Filter
Gain
0.0 dB
CW Filter
Gain
0.0 dB
RTTY Filter
Gain
0.0 dB

Real-Time Clock Button Meaning by Menu
Menu
BAND+
BAND-
RCL
STORE
Time
Calendar Menu
Calendar Menu
Calendar Format**
DSP Main Menu*
Calendar
Time Menu
Time Menu
Calendar Format**
DSP Main Menu*
Calendar Format
Toggle Format
Toggle Format
Year Menu
Calendar Menu
Year
Increment Year
Decrement Year
Month Menu
Time Menu
Month
Increment Month
Decrement Month
Date Menu
Time Menu
Date
Increment Date
Decrement Date
Hour Menu
Time Menu
Hour
Increment Hour
Decrement Hour
Minute Menu
Time Menu
Minute
Increment Minute
Decrement Minute
Time Menu
Time Menu
* Filter is the primary menu in RTTY mode; Main is the primary menu in CW and SSB modes
** Only when DSP is active; otherwise sends you to DSP BYPASS Menu
Button Action by Menu
Menu*
BAND+
BAND-
RCL
STORE
Primary (USB & CW)
Toggle Noise Reduction
Toggle notch filter**
Next Menu
Next Noise Reduction Value
Filter
Increase Width, Center, Upper or lower cut off
Decrease Width, Center, Upper or lower cut off
Next Menu
Move to next parameter to edit
Bypass
DSP On
DSP Bypass
Next Menu
Main Menu
Noise Reduction
Increase Decay or Beta
Decrease Decay or Beta
Next Menu
Move to next parameter to edit
Notch
Increase Decay or Beta
Decrease Decay or Beta
Next Menu
Move to next parameter to edit
Gain
Increase Gain
Decrease Gain
Next Menu
Firmware Version
* Filter is the primary menu in RTTY mode; Main is the primary menu in CW and SSB modes
** Only in SSB mode
Revision History
Date
Revision
Description
January 15, 2015
A
Initial release
March 03, 2015
B
Move Filter Status Display to top.  Correct errors to explain how to exit the DSP Bypass menu when the KDSP2 is disabled.  Add title page.