
5760.000 = 144.000 standard
LP: < 3.5 dB NF, > 17 dB G
1 mW min. to 10W max. Adjustable
DEM Part Number 5760-144K, CK and 5760-144LPK and CK
5.7 GHz. Transverter, Low P ow er Trans ver t e r, Kit and Complete Kit
Specifications
Preliminary:
This document is found on line at http://01895fa.netsolhost.com/PDF/Manuals/5760144CK_RevE.pdf . It contains blue clickable links with pictured examples of the procedure or
process described for cor r ect asse mbly.
The 5760-144CK and 5760 -144LPCK is a complete kit version of the 5760-144 and the
5760-144 Low Power transverter. In our Complete Kit version, you receive all 3 circuit board kits,
the 5760K (transverter PCB), the TC and the DIGILO synthesizer with a prepped extruded
aluminum enclosure, mounting plate, and all necessary hardware and connectors to get you on the
air. When completed, you will only need to supply a TR switch, Antenna and a 2 meter
transceiver. The 5760K is a PC board kit originally designed by W1GHZ and Down East
Microwave Inc. When W1GHZ (ex N1BWT) first designed and released the details of this
transverter in NOV. 1997 QEX, it was a basic PC board design with some details of how to
interface it with a few circuits to produce a simple state of the art transverter. DEMI has refined the
design and produced a one basic PCB Kit (Low Power) and two Complete Kits (Low Power and a
3 watt version) with all of the interfacing required.
In this transverter kit, the DEM TC is the interface circuit board that allows the use of up to a
10 watt 144 MHz transceiver. It contains TX and RX level adjustments. It provides all of the DC
and RF switching functions for the transverter actuated by it’s keying circuit that is either PTT-L (to
ground) or PTT-H (+ voltage) on transmit. It also supplies all internal biasing of the transverter and
external switching functions for TR switches, PAs, and LNAs. It also contains a 9 Volt 1.5 amp
voltage regulator to supply the regulated DC power to the transverter.
The DIGILO synthesizer (the LO) provides a nominal -10 dBm outp ut at 5616 MHz. for 144
MHz IF operation. The transverter PCB accepts the LO input and amplifies it to the correct level
with a test port for tune-up before the signal is injected into the mixers on the transverter board.
The 5760 MHz TX and RX signals are provided through 2 separate SMA type connect or s. The TX
and RX connectors are spaced correctly to allow a direct connection of common SMA relay to
complete the system and allow the use of a common antenna connection.
This assembly manual assumes that the complete kit version (5760-144CK or 5760144LPCK) is being assembled but is also used for the 5760K, the PC board kit version. Use what
is required from this document for the different assemblies.
All kits include the PCB, all components, pipe caps, connectors, required hardware, and a
CNC machined circuit board mounting plate. This plate is the key to the success and reliability of
the transverter. The plate is used as a fixture to attach the pipe cap filters to the circuit board. It
aligns the pipe caps in the correct position and then prevents scorching of the PCB while sweating
the pipe caps to the PCB. After assembly of the pipe caps, the mounting plate provides support to
the circuit board to prevent cracking of components and damaging ground vias. After assembly,
the plate provides easy attachment of standard SMA connectors used for tune-up and final use.
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There are 2 main requirements for the completion of this kit. You will need to “Sweat” the pipe
caps in place on the circuit board. This r eq ui res a pr opa ne tor ch. A standard soldering iron will
not work! Second, you will need a way to detect RF power at 5 cm frequencies to aid in tune-up.
This can be done with a detector diode, a microwave milli-watt power meter or a spectrum
analyzer. The filters need to be tuned after assembly! There are five of them in the low power
version and seven in the 3 watt unit. Both transverters will not work without correct alignment of the
filters!
Options:
Other than IF operating frequencies in the 2M band, there are no assembly options for the
5760 transverter board detailed in this manual. You are limited by the transverter’s PCB and
supplied components of what version you can assemble. The manual will describe one way of
assembly that will produce a state of the art 5760 MHz. transverter of choice. If you wish to
experiment with different gain stages and add-on filters and amplifiers, do it with caution.
Modifications should not be attempted without test equipment that will provide accurate power
levels and a spectrum analysis. DEMI will be more than happy to consult you with any of your
modifications, but will only assume full responsibility for this design if you use the supplied
components and assembly procedure. If you decide to stray from the original design or assemble
the 5760 PCB with your own components, you will assume the responsibility of the results. We will
answer any questions you may have but a repair and/or alignment by DEMI will only occur if
the transverter kit is in stock form! If you have any questions about this policy please consult us
first before proceeding with your own design or modification.
Assembly:
The TC should be assembled first per its assembly document. Some general assembly
options may be implemented to it depending on your requirements. The DEM TC has provisions
for an extra RXIF gain stage that may be required if you chose to tower mount the assembly or use
a large attenuator with a high power 144 MHz transceiver. The TC allows a 1mW to 10W common
or separate IF input that will require the proper configuration. It's your choice. The regulated and
unregulated voltage is switched to supply any additional stages such as a LNA or power amplifier
or the PTT circuit may be mirrored or inverted. The standard document of the TC has many more
details concerning its various options of operation. Please follow it for assembly and for the
completion of the complete kit version of the 5760-144 or 5760-144LP.
The DIGILO frequency can be set up and experimented with before the main
transverter assembly is started. The complete manual for it is on line at :
http://01895fa.netsolhost.com/PDF/Manuals/digilor18_9_1.pdf or you can wait until the test
procedure to set it up.
When configuring your system, please note that DEMI can supply a few external options. If
you require a “State of the Art“ noise figure, a 5 cm PHEMT preamplifier can be purchased. It is
part number L5ULNA as and assembled unit, L5ULNAK (board kit) or a complete kit version is
L5ULNACK. If you require more output power than the 3 watt version and have access to the
surplus market of 5 to 20 watt amps, be sure of the drive level of the amplifier. Most amplifiers may
only require 10 mW of drive which can be easily provided by the LP version of this kit. DEMI also
stocks relays, a basic sequencer and other accessories that will enable you to complete your 5760
MHz. station.
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