Total posts : 45366
It is really good when folks post here about their experiments and observations. Thanks for sharing yours.
It is not surprising that you observed a decrease in range with R18 installed. There was quite a discussion about this between PhilB and others in a blog a few years back. Unfortunately, my bookmarked link to this is dead.
PhilB, the SSTRAN designer and manufacturer, posted here that the unit is intended to see a collector load of about 800 ohms and with the SSTRAN design antenna this is accomplished by an impedance transformation using the variable cap to “tune” the circuit. I don’t have the link handy but I will edit it in here later.
I found it. You might also want to peruse the whole thread:
Given this information, it can be seen that my antenna did not present the proper load and I needed R18 to get a good waveform. Unfortunately, R18 is probably getting more power than my antenna.
My problem, as I mentioned, seems to be due to distortion rather than antenna bandwidth. If you can gain access to a scope, it would really be helpful for you and us if you can compare the output waveforms with and without R18. The audio enrichment may be due to decreasing distortion rather than increasing bandwidth.
With the wide disparity among antenna systems we all use it is a wonder it works at all. Congrats to Phil for what he has done with his design.