And the finished product.
Anyway, this was a fun project and this will be my main 75m AM transmitter. I really would like to pair it with an Alpha.
Jon
Congrats on getting it built, Jon! Mucho work and you learned a lot.
But... "Finished Product?" "Pair it with an Alpha?" Not so fast.
Now the honeymoon is over and the hard work starts to see how clean it is and to optimize it. Next: Some formal, systemized data tests.
1) Run a 50 Hz triangle audio wave thru and see how it looks, input compared to output.
2) Also, run a 50 Hz square wave thru to see how it handles it.
3) Then run a 2-tone test to see how clean it looks up and down the band on your SDR spectrum display.
4) Do a sinewave audio sweep from 30 Hz to ~10 KHz and see how true the sinewave stays and how flat it is across the audio spectrum. This will let you EQ it with confidence knowing that there are no band-aids covering up problems.
You may find you need some work before amplifying it thru a big amp. The 2-tone will tell a lot. Once you get the results, there are a list of things you can look at to improve things. I can help you zero in. (negative feedback, heavier loading, voltage stability, capacitive shunting, general IMD improvements, etc.)
Post the screen shots and data results of the tests above and put your BAs on the table, mate!
T
