Re: si5351a CLK drive levels in uBITX #ubitx


I have several homebrew projects with Minicircuits diode DBMs and si5351 VFO/BFO/carrier oscillators.

I first tried si5351 clocks at all output levels via a 3dB 50 ohm pad into an SBL1 with unconvincing results. I seem to recall a scope on the clock pin showed significant loading when attached to the mixer LO port. 

I then inserted a 74HC04 squarer and a bigger pad with much better results, but it stops squaring at the higher end of HF. 

In my last build, a G6LBQ Bitx, I settled on a single stage 2n2222 common emitter buffer/amp (with broadband bifilar tapped (10T FT37-43) inductor) between the si5351 clock (running at 2mA) and an ADE-1, which gave good results. 
Just sharin', YMMV.  

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