"I was debating about if I was going to put up a video or not" ->Next time that happens, no need to debate, just do it 🙂 Even if things might appear repetetive, like your common emitter biasing process, I am sure many of us don't mind seeing it the 100th time. On the contrary, most will appreciate it. Don't forget that your video quality and presentation skills have also improved over time, so while some content may be repetetive in nature, the presentation is not. Good video!
Thanks for the feedback, it's much appreciated. I'm conscious the biasing is mostly the same each time, but as you say, keeping it in is probably the best way ahead.
@@CharlieMorrisZL2CTM, if you don't post new videos I just watch the old ones over again, so I'm sure your new video will have something different in it. :)
Typically people would run the two stages the other way around, voltage gain then emitter follower. The emitter follow can be configured to drive 50 ohms directly, saving the fuss of a output transformer. The voltage gain stage will still be ample buffering and isolation for this purpose. The emitter follower could derive its bias from the voltage gain stage saving bias and coupling cap. But you cant argue with stuff that works! So jobs a good'un! de G0AFV
I've been digging around in Grob's Basic Electronics, and in Chapters 28 and 29 he touches Beta dc and Beta ac and says they are basically equivalent. Have you experimented trying to determine these values? I am having trouble accepting Beta ac = fT/op freq..
"I was debating about if I was going to put up a video or not" ->Next time that happens, no need to debate, just do it 🙂 Even if things might appear repetetive, like your common emitter biasing process, I am sure many of us don't mind seeing it the 100th time. On the contrary, most will appreciate it. Don't forget that your video quality and presentation skills have also improved over time, so while some content may be repetetive in nature, the presentation is not. Good video!
Thanks for the feedback, it's much appreciated. I'm conscious the biasing is mostly the same each time, but as you say, keeping it in is probably the best way ahead.
@@CharlieMorrisZL2CTM, if you don't post new videos I just watch the old ones over again, so I'm sure your new video will have something different in it. :)
coming along nicely.
Yes, quite happy with the VFO.
Typically people would run the two stages the other way around, voltage gain then emitter follower. The emitter follow can be configured to drive 50 ohms directly, saving the fuss of a output transformer. The voltage gain stage will still be ample buffering and isolation for this purpose. The emitter follower could derive its bias from the voltage gain stage saving bias and coupling cap.
But you cant argue with stuff that works! So jobs a good'un!
de G0AFV
That is interesting thanks. I thought buffering the osc early would be the better option. I'll have to remember that for next time. Cheers.
Beautiful work and explanation
Thanks for the feedback. I'm pleased it was useful.
I've been digging around in Grob's Basic Electronics, and in Chapters 28 and 29 he touches Beta dc and Beta ac and says they are basically equivalent. Have you experimented trying to determine these values? I am having trouble accepting Beta ac = fT/op freq..
No, not empirically. I have tended to use the text books. That might be something to look into at some stage.
@@CharlieMorrisZL2CTM I'm sure I saw in a video you used a NanoVNA to measure the R-in. Perhaps the data exists
Reduction gear on the tuning cap. Nice.
Yes. It works very well.
No matter how many times you repeat, we have no quams about it.. i enjoy every video and always learn heaps from you.. Thank you 8P5DG
Thanks for the feedback. The videos are rough and ready, but that's how I flow. 73.