Si5351a Synthesiser


So tonight i bout together one of 3 QRP Labs Si 5351a kits that I bought, not for WSPR use, but for future CW or SSB transmitter projects. The synth IC itself is awesome, 3 individually programmable square wave outputs. The kit went together ok, a couple od minor annoyances. The footprints used for the 2 transistors were wrong for the parts being used, and the spacings were kind of wring, there is so much more room on the board that it could have been spaced out better so the resistors did not sit under the cap of the transistors, and the SMA pads were about 1mm too short and required fiddling and spacing off the board before soldering,  anyway, thats about all i can bitch about HIHI.


Parts laied out for install, 3 SMA connectors are not included in the kit.


Resistors installed.


Caps and voltage regulator installed.


Transistors installed.


Final product with headers and SMA connectors installed. Next i will make a board to mount this on, supply power to the 4 different 5v pins???? not sure if it needs 4 different voltage lines, but according to the pinout it does, will need to look into this more. Next job will be to code up some Arduino code to test it and then turn it into a VFO.


One thought on “Si5351a Synthesiser

  1. there is some code written by Alf VK2YAC on QRP Labs web site, I have just built OCXO version and am about to start testing.

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