QRP ? 
what does it mean?
In amateur radio, QRP refers to low-power transmission. The term comes from the abbreviation for "Reduce transmit power" from the Q key and is the counterpart of QRO. By definition, the transmitter output power must not exceed 5 W in CW and 10 W in SSB.
Disadvantages
- Weak signals, such as those produced by a low-power QRP transmitter, are often overlaid by all kinds of interference, which makes reception significantly more difficult. In addition, a weak signal easily "disappears" due to fluctuations in the stability of the transmission path, it is subject to fading. This reduces the probability of a secure connection.
- With weak signals, the transmitted information is often difficult to read, making it difficult to hold a conversation. Sometimes it only succeeds in transmitting little more than the call sign. It must be mentioned here that with QRP operation, the fact of the radio connection itself often replaces the connection content that a secure connection would have offered.
- Not every radio partner understands the greater effort that is required to be able to record a weak station that could also have sent with higher power.
Advantages
- One appeal of QRP is not going to high power when QRP is still usable.
- A QRP transmitter with a low output power consumes little energy and is usually small, light, easy to set up (do-it-yourself) and possibly battery-operated.
- Due to the low transmission power, QRP transmitters cause less interference and less influence on other devices.
- Simple portable operation is possible with the mostly lightweight transceivers.
Elecraft K2
Elecraft's K2 is designed for use at home and on the go. The low reception current of the K2
(approx. 150 mA in battery saving mode) enables mobile operation with small gel cell batteries.
The K2 even includes an option for a 2.9Ah internal battery. Excellent sensitivity and dynamic range, Full QSK break-in (diode switched), Adjustable RX/TX CW pitch, High-speed memory keyers, selectable RX sideband, and sharp IF Crystal filters become standard.
👉 Elecraft K2 Homepage 👉 Elecraft K2 Owners Manual
My K2 is equipped with :
- KAF2 Audio filter and real time clock
- KSB2 SSB-unit
- KNB2 High performance noise blanker
- K160M 160M and 2. RX-Port
- KIO2 RS-232-Com Port and Aux I/0
- KAT2 Automatic Antennatuner there is also an option "KBT2" - internal Accu, which I didn't install because my K2 is only used in the shack.
In addition, the Ten-Tec 1208 50MHz Transverter is connected.
Standard features
- Tough, attractive case
- Small, portable size: 2.9 x 7.8 x 8.2 inches (H x W x D).
- Weight 3,3lbs. (without internal options)
- 80-10 meters; 160 m optional
- Efficient 12 volt operation (10 - 15 V) for at home or on the go
- Power consumption only 150 mA (battery saving mode)
- CW only or SSB/CW + digital modes with SSB option
- Backlit LCD and LED bargraph; Day/night settings
- PLL synthesized - low phase noise
- Microprocessor controlled
- 3 transverter bands; programmable display, IF, power
- Dual VFOs with split operation
- Direct keyboard entry of frequencies and memory channels
- RIT and XIT with four offset ranges
- Built-in high-efficiency speaker
- Memory Mode, VFO A/B, Split, RX Filter, etc.
- Simple menu system for advanced settings. (Up to two menu functions can be assigned to the two programmable function keys on the front panel.)
- Space for additional ports on the back
- Intelligent Band Scanning Mode
Receiver
- Low noise single conversion superhet receiver
- Double balanced diode mixer for excellent dynamic range
- Receive sensitivity: 0.15uV (preamp on, typical)
- Narrow amateur band, double-tuned bandpass
- RX/TX filter, relay switched for better IMD response
- Smooth, fast IF-derived AGC (no "popping")
- Switchable preamp and attenuator
- IF with variable bandwidth, crystal filtering
- Multiple choices for VFO tuning rate
- 10 Hz tuning resolution
- Bar graph S/RF OUT/ALC meter
- Adjustable squelch
Transmitter
- Adjustable 0.1-15W (K2), 0.1-100W (K2/100)
- Rugged, SWR-protected, push-pull PA transistors
- Programmable current limit for battery operation
- Harmonics and spurious outputs: Better than -40 dBc
CW features
- Fully diode-switched notch with variable QSK delay (at both QRP and 100W levels)
- 9 memory keyer; iambic A and B; adjustable weight
- 9-50 wpm (internal keyer); 70+ wpm (external keying)
- Programmable message repeat interval
- Simultaneous computer and paddle CW keystrokes
- Quartz filter with variable bandwidth (approx. 200 - 2000 Hz)
- Adjustable RX CW offset with tracking TX side tone.
- Selectable opposite sideband RX for QRM reduction
KAF2 Audio Filter and Real-Time Clock
The KAF2 offers an elliptical LC low pass filter and a narrow band pass filter for CW or data use. The low-pass filter attenuates noise and high-frequency QRM without affecting voice or data signals. The low-noise, two-stage active bandpass filter helps capture weak CW signals and can be turned on or off from the front panel. In addition to two audio filter settings, the KAF2 includes a 24-hour real-time clock/calendar with its own multi-year display emergency battery. Just tap the DISPLAY button to see the time or date on the K2's LCD! Supports MM/DD and DD/MM date formats.
KSB2 SSB Adapter
The KSB2 adds SSB and data modes to the basic K2 transceiver. Includes an optimized 7-pole 2.2kHz crystal filter.
Can be used with almost any dynamic or condenser microphone.
Specifications
- Quartz filter bandwidth approx. 2.3 kHz at -6 dB; 6/60 dB form factor approx. 2:1
- Carrier rejection -40 dB or better (typical)
- Speech compressor compression ratios: 1:1, 2:1, 3:1, 4:1
- Power consumption 10-15mA
- Size 4.1 x 2.2 inches (10.4 x 5.6 cm)
KNB2 Noise Blanker
Noise blanker option for the K2
The KNB2 eliminates most impulse noise, including that from power lines.
Specifications
- Blank widths NB1 - 10 µS; NB2 - 70 µs
- Power consumption Approx. 13 mA when on, 2 mA when off
- Size 2.3 x 1.4 inches (58 x 36 mm)
K160M - 160M and 2nd RX Port
Adds 160 meters of TX/RX and a second RX antenna input (usable for all bands).
Also supports transverters,
that require split TX/RX paths.
Specifications
- 160 m frequency range: 1.8 to 2.0 MHz
- Output power: 10 watts (nominal), adjustable to less than 0.5 W
- Receive antenna switch
- Impedance 50 ohms
- Isolation > 50 dB between RX ant. socket and main antenna socket (J4)
- Applicability all bands (independent selection on each band)
- Current drain: 0mA
- Size: 6.6 x 2 cm (2.6 x 0.8 inch)
KIO2 RS-232 Interface Aux I/0
With the KIO2 installed, you can control the K2 entirely by computer and you don't need an external level converter,
as the KIO2 offers true RS-232 levels. Compatible with most competition and logging software, as well as ours
own K2VOICE and K2REMOTE programs. The KIO2 Programmer's Reference provides extensive information for those
who write custom K2 control programs.
Note: The KPA100 option for the K2/100 includes an RS-232 interface. The KIO2 is only required for the base, 15W K2, without KPA100.
Specifications
- RS-232 interface:
- Data rate and format: 4800 baud, 8 data bits, no parity, 2 stop bits
- handshaking None
- ESD protection: +/- 15 kV; Signal lines HF-filtered and shielded
- Power consumption: 5 to 10 mA (typ.)
- Size: (KIO2 PC board) 1.5"(L) x 1.5"(D) x 0.5"(H) (3.8 x 3.8 x 12 cm)
KAT2 Automatic Antenna Tuner
With the KAT2 you can connect almost any antenna directly to the K2 and use it on all bands (160-10 m).
Two antenna sockets are provided - with the ANT 1/2 switch you can immediately A/B test both antennas for any signal.
Uses all latching relays so current drain is zero except when voting.
Specifications
- L - C ranges: L: approx. 0-20 µH in 256 steps; C: approx. 0-2400 pF in 256 steps
- Network type: L network (L series, shunt C); C switchable to transceiver or antenna side
- Adjusted SWR range: Up to 10:1 typ. (varies by band; smaller range on lowest/highest bands)
- Tuning time: 1 to 5 seconds typical for initial tuning; < 1/2 sec to recall saved settings
- SWR display: 1.0:1 to 9.9:1
- Power display: 0-20 watts (approx.); Forward and reflected power in 0.1W increments
- Power Consumption: Approx. 10-30mA during TUNE; < 5 mA at all other times
- Size: 4.2"(L) x 1.6"(D) x 1.5"(H) (10.7 x 4.0 x 3.8 cm)
Ten-Tec 1208 - 50MHz Transverter
the "magic band" for the K2
Ten-Tec's Model 1208 transverter is easy to connect and brings the 6 meter band over the 10 meter band to the K2.
To do this, the 1208 is connected to the K2 using a PL cable and the "TRN" item is called up in the K2 menu, the parameters are set and
we're ready to go 😉
The antenna I use on 50MHz is the Diamond V2000 at about 9ft above ground.
QRP Labs QCX Mini
The "QCX-mini" (QRP Labs Xcvr - mini): a feature-rich, high-performance single-band 5W CW transceiver kit with WSPR beacon
and built-in adjustment and test equipment. It is specially designed for portable operation,
where small size, weight and power consumption are important. Available for 160, 80, 60, 40, 30, 20 or 17m tapes.
Experimental use on 15, 12, 10 or 6 m (lower output power and reduced sensitivity).
👉 QRP Labs 👉 QCX Manual
/p - friendly features
- Small size: 95 x 63 x 25mm body (including keypads)
- Low power consumption (e.g. 58 mA reception current, with 12 V supply and switched off display backlight)
- Light weight, 202 grams
- Tough extruded aluminum body
- All-metal BNC short connector, screwed to housing
technical specification
- Easy to build, two-board design, board with main circuit and connectors, display panel board with LCD; All control boards mounted on a push-out sub-board. No wiring, all controls and connectors are mounted on the board
- Professional quality double-sided, thru-hole, screen-printed circuit boards
- You can choose a single band, 160, 80, 60, 40, 30, 20 or 17 m
- approx. 3-5 W CW output (depending on supply voltage)
- 7-14V recommended supply voltage
- Class E amplifier
- 7-element low-pass filter ensures regulatory compliance
- CW envelope shaping to remove key clicks
- High performance receiver with at least 50dB of unwanted sideband rejection
- 200 Hz CW filter without ringing
- Si5351A Synthetic VFO with encoder tuning
- 16 x 2 yellow/green LCD screen
- Iambic keyer or straight key option included in firmware
- Simple digital signal processing assisted CW decoder displayed on screen in real time
- S meter on screen
- Real time clock on screen (not battery backed up)
- Full or half QSK operation with fast semiconductor transmit/receive switching
- Frequency presets, VFO A/B split operation, RIT, configurable CW offset
- Configurable sidetone frequency and volume
- Connectors: 2.1mm barrel power connector, 3.5mm keyer jack, 3.5mm stereo headphone jack, 3.5mm stereo PTT jack, 3 .5mm stereo jack for CAT control, BNC RF out
- Built-in test signal generator and settings menu to perform simple setup adjustments
- Built-in test equipment: voltmeter, RF power meter, frequency counter, signal generator
- Beacon mode supporting automatic CW, FSKCW or WSPR operation
- GPS interface for reference frequency calibration and time measurement (for WSPR beacon)
- CAT control interface
- Optional 50W PA Kit
- Optional extruded, cut/drilled/laser etched black anodized aluminum body
CW 4 ever 😉
homemade Keyer
tiny paddle by N6ARA
the fully assembled Tiny Paddle from N6ARA , ready to use with QCX mini
Small and light iambic button. Intended for use as backup paddles for field operations or ultra-lightweight radios,
here with separate 3.5 mm audio extension cable 3FT / 3D-printed TinyPaddle holder (see above)
Antennas
permanently installed
21ft Wire Fishing Rod Vertical with 9:1 MTFT (left) mounted on the fence, the wire is coiled onto the rod and at the top fastened by a luster clamp
the Diamond V-2000 50/144/433 MHz on a approx. 9ft long tripod - mast tube, mounted on a concrete - umbrella stand
portable antennas
C-WHIP Antenne, 17m, 3/8"
- Connector : 3/8"
- Length : 260 cm
- Max. Power : 250 W
Diamond Magmount PL-SP-M
/portable stuff
LOGILINK Powerbank PA0273, 10.000 mAh, Solar
- Integrated solar panel
- Ultra-fast charging with USB-C PD 2.0 / USB-A QC 3.0
- Built-in LED lamp
- With extendable stand
- Battery type: lithium polymer
- Output: USB A + Type C
- Input: microUSB + Type C
- Capacity: 10,000mAh
- Input: 5V / 2A
- Output: 5 V-/ 3 A
- Protection class: IP44
- Material housing: plastic
- Color: Black
- Weight: 285g
- Dimensions (LxWxH): 163x84x18 mm