RF-KIT RF2K-S Guide

Bedienungs- und Installationsanleitung RF-KIT Linearverstärker RF2K-S
Assembly and adjustment instructions
for linear amplier RF2K-S
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Assembly and adjustment instructions RF-KIT Power Amplifier RF2K-S
Table of contents
1. Explanation of symbols, Environment protection 3
1.1 Explanation of symbols 3
1.2 Environment protection 3
1.3 Transport package 3
Step 1: Unpacking the device 4
Step 2: Removing the housing cover 4
Step 3: Removing the front panel 4
Step 4: Installing current operating system
on Micro SD card 5
Step 5: Installing Raspberry Pi® 4 Model B 5
Step 6: Connection controller board with
Raspberry Pi® 4 Model B 6
Step 7: Connection Touch screen with
Raspberry Pi® 4 Model B 7
Step 8: Connection Touch screen with Controller board 7
Step 9: Preparatory work for alignment 8
Adjustment 9
Position of the potentiometers relevant for adjustment on the
Controller board 9
Position of the adjustment elements and measuring points on the
Tunerboard 10
Step 10: Adjustment voltage display 10
Dear customer,
Congratulations on your purchase of a RF-KIT linear amplier!
RF-KIT devices oer innovative and reliable technology, functionality and
appealing design.
If, in spite of our careful quality control, you have any reason to complain
or have a question about the device, please contact the dealer you trust or
even directly to RF-KIT.
vy 73 es gd dx de
RF-KIT Reinhard Förtsch
Heuleithe 14 · 91322 Gräfenberg
Germany
Tel.: [phone]
www.rf-kit.de
[e-mail]
Raspberry Pi®is a registered trademark of the Raspberry Pi Foundation.
© 2020 by RF-KIT Reinhard Förtsch
Errors and omissions excepted. The removal of the copyright notice and
the use of content, even in part, violates applicable law and is expressly
prohibited.
Step 11: Test of the frequency measurement
and the lowpass lter circuit 10
Adjustment power display 10
Step 12: Adjustment forward power display
(low) 10
Step 13: Adjustment forward power display
(high) 10
Step 14: Adjustment reected power display
(low) 11
Step 15: Adjustment reected power display
(high) 11
Step 16: Adjustment SWR-measuring bridge 11
Step 17: Looping in the PA module 12
Step 18: Adjustment display current consumption 12
Step 19: Severe Error Alarm 13
Step 20: Adjustment forward power display
(full power) 13
Step 21: Fine adjustment power display via the menu 13
Step 22: Optional power ne tuning via the menu 14

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Assembly and adjustment instructions RF-KIT Power Amplifier RF2K-S
1. Explanation of symbols, Environment protection
1.1 Explanation of symbols
Warnings
Warnings are marked by a warning triangle.
In addition, signal words indicate the nature
and severity of the consequences if the mea-
sures to avert the hazard are not followed.
The following signal words are used in this document:
NOTE means that property damage may occur.
WARNING means that serious or even life-threatening personal injury
may occur.
DANGER means that serious or life-threatening personal injury will
occur.
Important information without danger to people or proper-
ty is marked by the adjacent symbol. These informations are
boanded by lines above and below the text.
1.2 Important informations
Symbol Meaning
►Instruction
➔Reference to a position in the document
Enumeration/List entry
- Enumeration/List entry
(2nd level)
1.3 Environment protection
Disposal of packaging
The packaging protects the device against damage during transport. The
packaging materials are selected according to environmentally friendly
and disposal-related aspects and thus recyclable.
The return of the remaining packaging parts, such as packaging straps, PE
bags, etc., into the material cycle saves raw materials and reduces waste.
If you plan to dispose of the packing by yourself, please locate the nearest
recycling center.

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Assembly and adjustment instructions RF-KIT Power Amplifier RF2K-S
Step 1: Unpacking the device
►Open the shipping carton carefully and remove the device.
►After unpacking the device, inspect it for shipping damage.
►Report any damage immediately to the shipping company or dealer.
Keep the shipping carton.
►Place the device on a stable work surface and have ready the required
tools.
Step 2: Removing the housing cover
►Loosen 4 lateral countersunk screws and then
remove the housing cover.
Step 3: Removing the front panel
►Loosen 2 countersunk screws each on the left and right to detach the
front panel from the device frame.
Before the device can be used, any necessary adjustments must be
carried out!
A Raspberry Pi® 4 Model B must also be installed (not supplied).
In order to prevent the device from being put into operation without these
adjustments and installation works having been carried out, suitable mea-
sures have been taken which must be reversed for operation within the
scope of the adjustment and installation works.
Note:
The device is not ready for operation when de-
livered! Although it can be switched on, it will not
generate any HF-power.
To carry out the adjustments you need some tools and measuring instru-
ments:
Phillips screwdriver and small screwdriver
Reference wattmeter
Digital Multimeter
Soldering station
In addition, the device must be connected to a control transmitter and an
dummy load:
Control transmitter (TRX) with adjustable output power
2 coaxial cables (approx. 1 m) with correctly fitted connectors PL-259
50 Ω dummy load; load capacity min. 1 kW
For the internal cabling you need:
2x USB-cable (USB-Mini to USB; approx. 0.5 m)
1x HDMI-cable (HDMI-Micro to HDMI; approx. 0.5 m)
These 3 cables are included in the delivery, in addition to a power plug and
a piece of coaxial cable with SMA plug.

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Assembly and adjustment instructions RF-KIT Power Amplifier RF2K-S
Step 4: Installing current operating system on Micro SD card
The device is supplied with a Micro SD card, which must be loaded with
the current operating system for the device.
To download the latest operating system you need a so-called “FTP pro-
gram“ (e.g. “FileZilla“, “WinSCP“ or similar).
You can obtain the corresponding data as a Zip le from the following ad-
dresses:
Version “International“:
Server: Port: User: Password:
access816807157.webspace-data.io 22 u100014070-rf2ksi RF2K-S-int
Version “US“:
Server: Port: User: Password:
access816807157.webspace-data.io 22 u100014070-rf2ks_w RF2K-S-usa
Version “Canada“:
Server: Port: User: Password:
access816807157.webspace-data.io 22 u100014070-rf2ks_ve RF2K-S-ve
Save the downloaded and unzipped le to the supplied Micro SD card
using the disk imager software “Win32 Disk Imager“.
“Win32 Disk Imager“ is available as freeware for Microsoft Windows as a
version for installation. The free software must therefore be installed after
downloading, which requires administrative rights on the computer.
Installing a version of the operating system other than that
intended for your country will void the warranty.
Step 5: Installing Raspberry Pi® 4 Model B
►Remove 4 pre-assembled screws from the spacer bolts provided for
fixing the Raspberry Pi® 4 Model B.
►Insert the Micro SD card preprogrammed in Step 4 into the slot provi-
ded in the Raspberry Pi® 4 Model B.
(continued on next page)
►Disconnect the cable between the power supply and the power
switch (1).

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Assembly and adjustment instructions RF-KIT Power Amplifier RF2K-S
►Place the Raspberry Pi® 4 model B on the spacer bolts as shown in
the picture below and secure it with the 4 screws previously removed
from the spacer bolts.
Step 6: Connection controller board with Raspberry Pi® 4 Model B
Now the Raspberry Pi® 4 model B must be carefully connected to the
controller board, Touch screen (2) using the 3 cables supplied.
2 cables from the connection sockets at the rear panel for USB and LAN
are also to be connected with the Raspberry Pi® 4 model B.
Always take care to avoid any mechanical stress on soldered
sockets of all components.
Especially the HDMI sockets of the Raspberry Pi® 4 Model
B are wellknown to be particularly sensitive in this respect!
►Connect the USB cable already present in the device to
“D lower - USB“ on the Raspberry Pi® 4 Model B.
►Connect the LAN cable already present in the device to
“F- LAN“ on the Raspberry Pi® 4 Model B.
A
B
C
F
E
D
USB from the
rear panel
LAN from the rear panel
Raspberry Pi® 4 Model B:
A- Micro HMDI / B- Micro HMDI / C- Power supply / D, E - 2x USB /
F- LAN
1 2
5
4
3
Controller board: 1 - Mini USB / 2- Mini USB / 3- USB / 4- USB / 5- USB
►Connect “4- USB“ on the Controller board to “C- Power supply“
on the Raspberry Pi® 4 Model B.
C
4
►Connect “1- Mini USB“ on the Controller board to “D upper - USB“
on the Raspberry Pi® 4 Model B.
The socket “2- Mini USB“ of the Controller board will not be used and
therefore remains free.

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Assembly and adjustment instructions RF-KIT Power Amplifier RF2K-S
►Connect “H- USB“ of the Touch screen (2) to “E- USB“ on the
Raspberry Pi® 4 Model B.
E
H
Step 8: Connection Touch screen (2) to Controller board
►Connect “K- Power supply“ of the Touch screen (2) to “3- USB“ on the
Controller board.
3
Step 7: Connection Touch screen (2) to Raspberry Pi® 4 Model B
G
H
K
Touch screen: “G- HDMI“ / “H- USB“ / “K- Power supply“
►Connect “G- HDMI“ of the Touch screen (2) to “B- Micro HMDI“ on the
Raspberry Pi® 4 Model B.
B
G
Socket “A- Micro HMDI“ on the Raspberry Pi® 4 Model B will not be used
and therefore remains free.

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Assembly and adjustment instructions RF-KIT Power Amplifier RF2K-S
Step 9: Preparatory work for alignment
A suitable plug for the Power jack (9) is included in the delivery. With this
plug, together with a suciently dimensioned mains cable and a coun-
try-specic mains plug, the user has to prepare a mains cable suitable for at
least 16 A current consumption (cable cross-section >1.5 mm2).
A short piece of coaxial cable with one attached SMA plug (“Pigtail“) is also
included:
►Strip off approx. 15 mm of insulation at the free end of the “Pigtail“ and
tin it.
In the rear area of the power amplifier module, directly in front of the rear
panel, there is the free end of a white coaxial cable.
This coaxial cable normally lies at between the board of the power ampli-
er module and the rear panel and has been angled upwards for better
visibility in the following picture.
White coaxial cable
with free end
►Solder the “Pigtail“ to the free end of the white coax cable.
►Connect SMA-plug “Pigtail“ to TX/RX-Tuner-module.
Now the power amplier module is bypassed and the control signal is
looped through. All functions of the device can be tested in this way
without generating power.
►Check all plug connections for tight fit, freedom from mechanical
tension and correct connection.
►Connect TRX to Exciter input (17).
►Connect Dummy load to ANT1 (6).
►Establish PTT connection via PTT (7).
►Connect the device to earth via the Ground connector (11) on the
rear panel.
Use a cable with the shortest possible length and the largest possible
cross-section.
►Connect the unit to the mains using the power cable via the Power
jack (9) on the rear panel.

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Assembly and adjustment instructions RF-KIT Power Amplifier RF2K-S
Adjustment
Switch on the unit with On/Off (1). Wait until the main screen is displayed
on the Touch screen (2).
The following adjustments are made using setting
Tuner Mode: Auto - Bypass:
- Adjustment voltage display
- Test of frequency measurement and lowpass filter circuit
- Forward power display, reflected power display and SWR-display.
These power-based adjustments are carried out in the 20 m
band (14 MHz).
Fig. below: Position of the potentiometers relevant for the adjustment on
the Controller board.
0
I
Rear panel:
6
17
Front panel:
1
2
9
11
1 On/O
2 Touch screen
6 ANT 1
7 PTT
9 Power jack
11 Ground connector
17 Exciter input
7

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Assembly and adjustment instructions RF-KIT Power Amplifier RF2K-S
Step 10: Adjustment voltage display
►Adjust voltage display at the Touch screen (2)
(Menu →Calibration →Poti Config: “Indication area Voltage“)
with R26 on the Controller board to 53,5 V.
Step 11: Test of frequency measurement and lowpass filter circuit
►Set the transmit power of the TRX to 5 W (CW/AM/FM) reading on your
reference wattmeter.
►Connect TRX to Exciter input (17).
►Connect Dummy load to ANT1 (6).
►Operate PTT.
The frequency display of the PA should match that of the control transmit-
ter +/- 2 kHz.
►Check whether the display of the current band filter also changes on
the Touch screen (2) when the frequency or band is changed and
whether the correct band filter is displayed.
There are control LEDs on the Lowpass Filter Board:
►Check for all bands whether the band filters are also changed when
the frequency or band is changed and whether the correct band filter
is selected (corresponding LED lights up red).
►Release PTT, stop transmitting.
Position of the adjustment elements and measuring points on the
Tunerboard
R515 R502
C500
R526 R525
Adjustment power display
The following power-based adjustments are carried out in the 20 m band
(14 MHz).
Step 12: Adjustment forward power display (low)
►Set the transmit power of the TRX to 5 W (CW/AM/FM) reading on your
reference wattmeter.
►Connect TRX to Exciter input (17).
►Connect Dummy load to ANT1 (6).
►Operate PTT.
►Adjust R502 on the Tunerboard for 1.6 V at measuring point R525.
►Release PTT, stop transmitting.
Step 13: Adjustment forward power display (high)
►Set the transmit power of the TRX to at least 50 W or more (CW/AM/
FM) reading on your reference wattmeter.
►Connect TRX to Exciter input (17).
►Connect Dummy load to ANT1 (6).
►Operate PTT.
►Set R24 on the Controller board so that on the Touch screen (2)
(main screen) the transmit power supplied by the TRX is displayed with
the correct value as forward power.
►Release PTT, stop transmitting.

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Assembly and adjustment instructions RF-KIT Power Amplifier RF2K-S
Step 16: Adjustment SWR-measuring bridge
►Switch the device to “Standby“ using the switching area “Standby“.
►Choose the 6 m-Band (50 MHz).
►Set the transmit power of the TRX to 5 W (CW/AM/FM) reading on your
reference wattmeter.
►Connect TRX to Exciter input (17).
►Connect Dummy load to ANT1 (6).
►Operate PTT.
►Adjust C500 on the Tunerboard to display minimum SWR at the
Touch screen (2) (main screen).
Step 14: Adjustment reflected power display (low)
►Set the transmit power of the TRX to 5 W (CW/AM/FM) reading on your
reference wattmeter.
►Connect TRX to ANT 1 (6).
►Connect Dummy load to Exciter input (17).
►Operate PTT.
►Adjust R515 on the Tunerboard for 2.7 V at measuring point R526.
►Release PTT, stop transmitting.
Step 15: Adjustment reflected power display (high)
►Set the transmit power of the TRX to at least 50 W or more (CW/AM/
FM) reading on your reference wattmeter.
►Connect TRX to ANT 1 (6).
►Connect Dummy load to Exciter input (17).
►Operate PTT.
►Set R23 on the Controller board so that on the Touch screen (2)
(main screen) the transmit power supplied by the TRX is displayed with
the correct value as reflected power.
The bargraph of the reflected power on the main screen will deflect full,
but the digital power display will still show the value to be adjusted cor-
rectly.
►Release PTT, stop transmitting.

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Assembly and adjustment instructions RF-KIT Power Amplifier RF2K-S
Step 17: Looping in the PA module
►Disconnect SMA plug “Pigtail“ and unsolder its free end from the
white coaxial cable.
►Solder the free end of the white coaxial cable to the output of the PA
module.
White
coaxial cable
There are 2 bias jumpers on the PA module. On delivery both jumpers are
in position “BIAS OFF“.
►Set both jumpers to position “BIAS ON“.
Delivery status: “BIAS OFF“ Operating status: “BIAS ON“
Rear panel
Rear panel
Step 18: Adjustment display current consumption
►Remove SMA plug from input SMA socket PA module.
“BIAS ON“
►Switch the device to “Operate“ by tapping switching area Standby.
Now LED “53 V-On“ lights up.
►Connect TRX to Exciter input (17).
►Connect Dummy load to ANT1 (6).
►Set the transmit power of the TRX to 5 W (SSB).
►Operate PTT, whistle briefly into the microphone until both Bias-LED
light up green.
►Keep PTT pressed.
►Adjust Quiescent current with R25 on the Controller board until
3.6 A is displayed on the Touch screen (2).
►Release PTT, stop transmitting.
►Plug the SMA plug back into the input SMA socket PA module.
Bias-LED
LED: “53 V-On“
Fig. right: PA module

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Assembly and adjustment instructions RF-KIT Power Amplifier RF2K-S
Step 19: Severe Error Alarm
►Connect TRX to Exciter input (17).
►Connect Dummy load via Reference wattmeter to ANT1 (6).
►Tune TRX to a frequency in the 20 m band (14 MHz).
►Adjust R19 on the Controller board about 10 turns counterclockwise.
►Switch the device to “Operate“ by tapping switching area Standby.
►Set the transmit power of the TRX to 5 W (CW/AM/FM) reading on your
reference wattmeter.
►Operate PTT.
If a Severe Error Alarm is already triggered now, R19 on the
Controller board must be adjusted further counterclockwi-
se. This will continue until the alarm message disappears.
►Gradually increase the transmit power of the TRX until 500 W is dis-
played on the reference wattmeter (the power display of the PA
display may still show a different value, as it will be calibrated in the
next step).
►Keep PTT pressed.
►Adjust the PAF display with R19 on the Controller board until the
value “1100“ is displayed.
(Menu →Calibration →Poti Config: “Indication area PAF“)
►Release PTT, stop transmitting.
Step 20: Adjustment forward power display (full power)
This adjustment is carried out in the 80 m-Band (3.5 MHz).
►Connect TRX to Exciter input (17).
►Connect Dummy load via Reference wattmeter to ANT1 (6).
►Operate PTT.
►Slowly increase the TRX transmit power from 5 W until Reference
wattmeter reads 1000 W (CW/AM/FM).
►Set R24 on the Controller board so that on the Touch screen (2)
(main screen) Forward power is displayed with 1000 W.
►Release PTT, stop transmitting.
Step 21: Fine adjustment power display via the menu
Please also note the description in the operating instructions
(➔ page 14, “Oset Calibration“)
Go to
Menu →Calibration →Oset Calibration:
The unavoidable frequency-dependent deviations of the linearity of the
directional coupler used for internal power measurement can be minimi-
zed for each bandpass range. The adjustment should be performed at an
output power of 1 kW. Use your preferred reference wattmeter for the ad-
justment.
Selection of the bandpass range is done automatically during transmission.
The detected band is highlighted.
►Adjust the internal power display by tapping switching areas
> (increase value) respectively < (decrease value).
Brief actuation changes the value in the indication area Forward by 0.1 W.
Longer actuation changes the value continuously.
►Press the switching area Save to store the settings.
►Repeat this procedure for each bandpass range to be adjusted.

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Assembly and adjustment instructions RF-KIT Power Amplifier RF2K-S
Step 22: Optional power fine tuning via the menu
Please also note the description in the operating instructions
(➔ page 15, “Output Power Calibration“)
Go to
Menu →Calibration →Output Power Calibration:
The output power generated at a given control power can be adjusted op-
tionally within certain limits for each bandpass range.
The 6 m band requires a higher control power than the
other frequency ranges and should therefore always be set
to “100“.
Selection of the bandpass range is done automatically during transmission.
The detected band is highlighted.
►Adjust the output power by tapping switching areas
> (increase value) respectively < (decrease value).
Brief actuation changes Calibration Value by 1 digit.
Longer actuation changes the value continuously (factory setting: 100.0).
Display area Forward Power constantly informs you about the currently
generated output power.
►Press the switching area Save to store the settings.
►Repeat this procedure for each bandpass range to be adjusted.

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Assembly and adjustment instructions RF-KIT Power Amplifier RF2K-S

Bedienungs- und Installationsanleitung RF-KIT Linearverstärker RF2K-S
Reinhard Förtsch · DH3NAB
Heuleithe 14 · 91322 Gräfenberg
[e-mail] · www.rf-kit.de
.-. ..-. -....- -.- .. - .--. --- .-- . .-. .- -- .--. .-.. .. ..-. .. . .-.