CDG2000 High-end transceiver

Thanks to G3KBB, G3OCQ and G3SBI for their effort in making a transceiver, that can compete with the most expensive ones on the market.

During the process of building this transceiver we (OZ9MO and myself) have made some corrections primarily based on measurements but also based on our personal opinion to a specific circuit.

Some (maybe most) of the changes can be seen in the following PDF´s.


   Updated   Title

    28/07 04    Front-end board 

    28/07 04    Post Mixer Amp.

    28/07 04    Controller

    07/09 04    Syntesizer

    07/09 04    Syntesizer - translated

    28/07 04    Transmit exciter

    28/07 04    Transmit exciter corrections

    03/09 03    CW osc/Af amp/2 tone osc.

    07/09 04    Mod. for CW

    05/12 04    Changes to key and CW osc.

    11/09 03    IF amp.

    07/09 04    More remarks to IF amp.



       My CDG2000 



























Pic-A-Star Software Transmitter and Receiver

Thanks to G3XJP, Peter for sharing his knowledge with me too. Working with software for Pic´s and DSP´s this way has been - and still is - a real challenge. Without participation from the Yahoo-group members the project would not have reached this high perfection.









     My STAR














SWR meter

For details - take a look at the web site of F1FRV. That site is very good.



This SWR meter will be added to the STAR PA.















Current measurement

I found it nice to be able to monitor the current to the STAR PA. Several circuits were tested and the one I found best is shown here.


Now I have a DC voltage (or DC current) going from 0 (0 amp) to 3-4 V (20 amp). I can now monitor the current and later I can use that signal to shot down the PA if anything happens that causes the current to increase to more than a preset value.






Rubidium Frequency Standard

I finally managed to place the LPRO Rubidium Osc. in a box with a PowerSupply - a couple of distribution amplifiers - (thanks to OZ9MO) and a circuit to tell me if the oscilator has locked or not.

I have transformers at the output of the amplifiers to avoid "ground loops" - therefor the insulated BNC sockets.

Schematic of all this can be found here.

The LCD voltmeter on the front is for a future feature.

My tests with frequency adjustments can be seen here.






The Rubidium osc.

is placed under

the heatzink.
















An Automatic Antennatuner was described in the Danish Ham magasin "OZ" in dec. 2002 and the following months. The group that designed the unit called it ATU 2002. I do not know if there has been any description on the internet. The unit has a max power handling of approx. 100W. I am using it after my 150W PA and it seems to work fine. My main purpose was to correct bandedge SWR so the PA could see a near 50 ohm load. I do not expect the Tuner to handle all impedances with that power!



















to be described


New PA for 432MHz (1kW)

to be described


PA3AKE frontend

to be described



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