Re: Microphone level adjustment question - Update
I was surprised that nobody appears to be using a scope to set the drive level but that is not unlike the old days :) It appeared as though I might have both overdrive and when overdriven some stability issues in my kit.toggle quoted messageShow quoted text
Using G8OWB's documentation for PE1BWI's stability mod I added the 220 ohm and the 1,000 ohm resistors. Most of the harshness that I was hearing on the local receiver was gone but there were still strong hints of overdrive.
At this time I set all of the bias pots and the drive pot to their CCW position and performed the necessary alignment adjustments. I was careful to not bring up the drive pot (R83) to far.
Although my Bird43P will not read individual voice peaks it was registering about 8 watts PEP on a steady Ahhhhhh. While all of the roughness in the audio now seems to be gone I will have a good 400 MHz. scope available tomorrow and will take a look to see if it is still flat topping. I suspect that it is.
I will follow up with the results of the scope tests and let you know what the real PEP is on normal voice peaks. Not a lot different than adjusting a Central ELectronics 10B with no test equipment.
I received one comment about RF getting into the electret microphone elements. That comment should have be in a LARGE BOLD font as it is certainly the case with the BitX20A that I have :)
73 - Mike - K9JRI
--- In BITX20@..., "k9jri@..." <k9jri@...> wrote: