Ultimate-3
(dimensions 103x56x168mm). The topcover of the housing is replaced by a aluminium grid for better cooling.
There is a dual power supply inside (+5V and +PA).
The PA stage is equiped with 3x BS170 which will deliver a maximum outputpower of
about 1 Watt at 40m and lower bands
and are individually cooled with a mini heatsink.
The supply voltage (+PA) can be selected with a switch on the frontpanel from 5V or 7V to 9V
(low-, medium- or high power resp.).
A 5x2 pin header on the PCB of the U3 is mounted to upgrade the U3 Atmel chip (current version 3.09f).
On the frontpanel is a switch for the background-illumination of the display (high-, low intensity and off).
A 2.5 mm connector on the frontpanel can be used for a CW transmit key.
There is also a TX/RX relay inside with BNC connectors at the backside of the unit.
The Ultimate-3 is synchronised externally with the high performance Skylab SKM52 GPS module
(fitted in a separate plastic enclosure).
It gets the +5V from the Ultimate-3 and is internally stabilised to +3.3 V.
In this Ultimate-3 a maximum of six LowPassFilters can be mounted.
After the purchase of a NanoVNA the LowPassFilters have been measured.The NanoVna has a maximum number of 101 frequency points per sweep.
To increase this number NanoSaver app is used.
This app (which runs at a Windows machine) makes use of the calibration data in the calibrated NanoVna.
In that case the calibration data must be saved in memory slot 0.
The calibration is done with a BNC calkit (SOLT) of SDR-Kits, but can also be a sma- or N-type calkit.
After calibration of the NanoVna the insertionloss of the filters (inclusive the LPF test fixture)
is w.r.t. the BNC thru of the calkit.
For reference to the website of G0UPL about Ultimate3 click here
If you have a question/remark please contact me.March 7, 2022.
73, Kees PE0CWK
Ultimate-3
PE0CWK