I got the BITX 20/40 on the air this morning. The receiver has been working for a week or so, but as usual it was a bit of a struggle to tame the transmitter. I got up early this morning and started poking and probing. I played with the driver and final coils a bit. I had used the same trifilar toroids that I'd used in the BITX 17, but this rig didn't seem to like them. So I went with FT-50-37 bifilars -- that seemed to work better. That IRF-510 seems to put out about seven watts on 40. (I still need to tame the transmitter on 20). The 40 meter signal looked great on the 'scopes (RIGOL and Tek!). Shortly before 8 am I worked AD4SY who reported that I was filling his shack with booming audio. Life is good.
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Tube Radios • Re: Testing DIY triodes - Now that I've decided to focus on planar element designs I'm making fixtures to keep the parts reproducible. This is how the plates are made. It's a simple...
22 minutes ago