Homebrew sBitx Walkthrough

 

Here is a video walkthrough and quick homebrew sBitx update.  I've intergrated the PA into the rig and calibrated the Tx levels.  I am very pleased to get 20 clean watts CW out on all bands from 80-10.  All modes are working well.  Final calibration meant deriving all my own band settings and updating the sBitx hardware configuration file hw_settings.ini.  Since my analog build is unique I had to start from scratch with the configuration.  I tested transmit on each band through the LPF and check the signal quality and strengthh on the scope.

When I first installed the PA it worked great on 80 and 40 but on the higher bands the relays were chattering and buzzing.   I added .1uF caps to the DC lines and that fixed the problem on all bands except 10 meters.  Farhan suggested adding bypass caps to the GPIO lines that drive the transistors that control the relays.  As N2CQR says - "Bob was my uncle!"  That fixed it.  

The radio sounds great and I have been getting good audio reports.   Had a QSO yesterday with PV8AL,Helio in Brazil on 17 meters SSB.  I got a 5:7 signal report plus good audio.  If you've ever worked Helio you know you can sometimes here a rooster crowing in the background.  Not so this time.

Its scary - I'm running out of bugs and problems.  I better be careful what I wish for.

73,

Dean

KK4DAS