Elecraft K2 Transceiver with Upgrades

• Microcontroller firmware 2.04A
• I/O controller firmware 1.09
• KPA100 firmware F1.06
• Elecraft K2 Discontinued 80-10m SSW/CW, 15W, 2.9" x 7.8" x 8.2", 3.3 lbs
• Elecraft K2 Manual the errata covers assembly only.
• Elecraft K160RX 160m receiver module installed.
• Elecraft KAF2 audio filter and real-time clock installed.
• Elecraft KNB2 noise blanker installed.
• Elecraft KPA100 power amplifier and RS-232 interface installed.
• Elecraft KSB2 SSB adapter installed.
• Elecraft KIO Programmer's Reference
• NOT installed: Elecraft 60m and transverter adapter requires microcontroller firmware 2.04P or later and I/O controller firmware 1.09 or later
• NOT installed: Elecraft KDSP2 DSP filter and real time clock. See page 31 to access the software version numbers
• Nifty! Elecraft mini setup and operating guides might be a useful item to get.
• BFO
• ?? installed ?? Elecraft Encoder upgrade
• ?? installed ?? Elecraft Keying Mods requires software 2.04P or later. Therefore not installed?
• ?? installed ?? Elecraft KPA Upgrade can be used with KPA100 firmware revision 1.08 or higher, not required.
• ?? installed ?? Elecraft K2 PLL reference upgrade
• ?? installed ?? Elecraft Rev B kit

Antenna

• All measurements are rather inaccurate. Tape not pulled particularly tight. Branch does move a bit. Wind blows the tape somewhat.
• 46.5' from ground to tree branch.
• 52' from tree branch to top of chain link fence at the Koff's yard.
• 59' from tree branch to bottom of siding on rear of house.
• 69' from tree branch to top of chain link fence at the Zwany's yard.

Operating Notes

• K2 can handle an SWR of 2:1
• Battery for real-time clock may be dead. Does not retain time across a power cycle. CR2032 or equivalent required.
• Need a calibrated signal source to set S-9 level.
• VFO linearization, using "CAL PLL", not attempted.
• Filter settings, using "CAL FIL", not attempted.
• Transmit current limit recommended to be set to 3.5A or less. Set and confirmed 2017-12-25.
• "8r hold" function must be enabled when transmitting with the KPA100. See page 49 of the KPA100 manual. Confirmed 2017-12-25
• S-meter calibrated to LO: 184, HI:18. Calibrated 2017-12-25.
• KPA100 temperature calibrated for 21C at 70F on 2017-12-25.
• General Operation
  • With KPA100 is installed, you should use only the SO239 antenna jack.
  • With KPA100 is installed, the BNC antenna connector should be kept covered by the supplied rubber cap.
  • When the K2/100 reduces power due to high SWR, you'll see the message HI REFL on the K2's LCD.
  • Initial tune-ups should be done in QRP mode (10 watts or less). Use only that amount of power required for your tuner to operate correctly.
  • The maximum recommended power for PSK31 mode is 40 W, and for higher duty cycle modes such as MFSK, 25 W.
  • RS-232 cable required is NOT standard. See page 61 of the KPA100 manual.
  • RS-232 parameters: 4800baud, 2 stop bits, 8 data bits, no parity, hardare handshaking off, local echo on, line-feed on.
  • Tap MODE to cycle through the operating modes: C = CW, L = LSB, U = USB, r = RTTY (if enabled).
  • The RF GAIN control should normally be set fully clockwise.
  • Adjust the AF GAIN control for comfortable volume.
  • The preamp provides about 14 dB gain. If you experience strong in-band interference, you may want to turn the preamp off.
  • 10 dB of attenuation can be switched in by turning on the attenuator. This is more effective than using the RF GAIN control in the case of strong-signal overload.
  • Tapping DISPLAY alternates between frequency, real-time-clock, and voltage/current display mode.
  • The current VFO frequency can be locked by holding the LOCK switch until "LOC" is displayed.
  • Use TUNE to key the transmitter. There will be on beep upon entering TUNE mode, and one beep upon leaving TUNE mode by tapping any switch or paddle.
  • To see actual power output, use TUNE. In "TUNE" mode, the display always shows the actual power output (except when the display is showing voltage and current via DISPLAY)
• Split Mode Operation
  • To enter SPLIT mode, hold SPLIT until the message "SPLIT" appears on the LCD. Holding SPLIT in again will display NOR (normal).
  • However, there are times when you only want to quickly listen on your transmit frequency, not switch VFOs. In this case you can hold in the REV switch (reverse), which temporarily swaps the VFOs. When you release REV, the LCD will return immediately to the receive frequency.
  • When using SPLIT, experienced operators can simultaneously hold in the REV switch and adjust the VFO knob--all with one hand--to quickly find a clear spot to transmit. (REV overrides VFO lock as described previously.)
  • play with "RIT and XIT" on page 98
• CW Operation
  • Keyer input requires stereo 1/8” phone plug, jack is an SJ-373
  • The K2 is supports paddles via a TRS (tip, ring, sleeve) socket. The sleeve is connected to a voltage source. The contacts of a paddle short the sleeve to either the tip or the ring to produce a series of dots or dashses via the internal keyer.
  • The plug on a straight key must be insulated to prevent the voltage on the sleeve from being shorted to the ring contact. Have accomplished this by wrapping the plug with clear tape and cutting away enough tape to provide bare metal for the sleeve and tip contacts while insulating the ring contact.
  • External Keying Auto-Detect via DOT and DASH lines will be pulled low simultaneously.
  • To use a hand key or external keying device, select INP HAND using the menu. Use the "tip" contact (DOT) of the key jack
  • With PDLn selected, the "tip" contact on the stereo key jack is DOT and "ring" (the middle contact) is DASH. PDLr is the reverse.
  • In CW mode, you must send a few CW characters or press TUNE to allow the ALC (automatic level control) to lock-in the new power level.
  • In CW mode, the frequency shown on the LCD takes into account an offset equal to your sidetone pitch. This allows you to determine a station's actual carrier frequency by matching their pitch to your sidetone, rather than by zero-beating the signal. The SPOT switch can be used for this purpose.
  • If you want to try out the keying without actually transmitting, hold the VOX switch until the display shows "TEST". The mode letter C on the LCD will flash to remind you that you have disabled transmission. Holding the VOX switch in again returns to "OPERate".
  • Use AFIL to select an audio filter. In CW and CW reverse modes, and leave FL2-4 at the narrower factory defaults (0.7, 0.4, and 0.2).
  • Use SPOT to match the received frequency. Using SPOT does not mute the receiver. Tune the radio while using SPOT till the sending station's signal "disappears" under the sidetone annunciated by SPOT.
• NEXT item is "Message Memories" on page 101
• K2REMOTE provides flexible remote control of the K2, even over the Internet (using TCP/IP).
• K2VOICE is a voice feedback program for the K2 which make the K2 fully usable by hams who are unable to see the normal K2 controls and displays.
• With K160RX option installed, you'll have a separate receive antenna jack (BNC) on the lower rear panel.

Using the K160RX

Using the Audio Filter

Using the K2/100 at High Power

Using The Noise Blanker

You should leave the noise blanker OFF unless noise is present. If signals become degraded with the noise blanker turned on, try a different setting, or try turning off the preamp.

The NB button controls the noise blanker mode, which is OFF on power-up. If you hear pulse-type noise, first tap NB to select "NB1" (narrow pulse width). The "NB" annunciator on the LCD will turn on. If this does not improve the signal to noise ratio, tap NB again to select "NB2" (wide pulse width).

Note: The wider pulse width can result in audible modulation of strong signals, especially in CW mode.

The LEVEL button controls the blanking threshold. When you turn on the K2, the threshold will be set to "HITHR". This means that only strong noise pulses will activate the blanker, which minimizes received signal degradation. However, on a quiet band or when using low-efficiency antennas, you may find the "LOTHR" setting more effective. This is especially true when operating mobile, since a whip antenna may be inefficient yet still pick up ignition noise. "LOTHR" is selected by holding LEVEL, and holding it again switches back to "HITHR".

The "NB" annunciator will blink whenever L O T H R is in use. This serves as a reminder that any signal degradation that you hear may be due to the low blanking threshold.

Using The SSB Adapter

• Tap AGC to select SLO AGC (recommended for all data modes).
• See page 21ff of the manual.

Using the RS-232 Interface

• Do not use a pre-assembled cable of any kind between the KPA100 and a computer. Some of J8's pins provide special signals not intended for use with an RS-232 interface, and you could damage the K2, KPA100, or the computer if these lines are used incorrectly.
• DB-9 male connects to K2
• DB-9 Pinout
  • Pin 1: DCD -- bare shield wire connected at KPA100 DB-9 only
  • Pin 2: RxD -- straight thru to PC connected DB-9 -- default high from KPA-100
  • Pin 3: TxD -- straight thru to PC connected DB-9 -- default high from Mac
  • Pin 4: DTR -- unused and unconnected -- default low from Mac
  • Pin 5: Gnd -- straight thru to PC connected DB-9 u
  • Pin 6: DSR -- unused and unconnected-- default low from KPA-100
  • Pin 7: RTS -- connect to CTS at PC connected DB-9 only -- default low from Mac
  • Pin 8: CTS -- connect to RTS at PC connected DB-9 only -- default low from KPA-100
  • Pin 9: RI -- unused and unconnected
  • See KPA-100 Manual page 61f
• use the command

  screen /dev/cu.usbserial-A600MHSJ 4800,echo,cs8

  to connec to the K2.
• with minimal testing have been able to query the K2 and obtain information as well as change settings (change band via "SW01;")