On Jun 20, 2018, at 11:52 AM, Ashhar Farhan <farhanbox@...> wrote:
I am reading this thread. I really have no comments except that there is no objective measurement or audio clip that i can comment upon. Hence let me make some general comments.
As old timers will testify, i never recommend, leave alone ship a circuit that i havent built at least twice and operated them on air for at least three or four mornings. I did extensive on-air tests as well as distortion measurements on the new? audio amplifier before shipping it out.
The thing that I have been unhappy about is that I had to reduce the overall gain. I took a decision to not revise the circuit too much but fix the excessive gain that can distort without the AGC. If we had the luxury of AGC, we could have lived with higher gain. The radio is now optimised to work well into 21 mhz. At 28 mhz, the gain is enough for headphone operations but speaker output will work only in a quite room.?
I continue to use the v4 regularly with FT8 as well as local ragchew on 40 meters. I have asked production to ship me a latest batch board to test it out. This is just in case there has been a mistake in terms of change of component values. I will report. This back in a day.?
