Re: Hilltopper mod performance

Charles W. Powell
 

I had time this afternoon to complete the audio mod to my Hilltopper 30, by replacing R5 and C22.  It makes an audible difference, putting a signal at -107 dBm from faint to fair.  If i turned the RF gain down to where it is roughly minimum, I could still hear the -107 dBm signal input.  At full gain, it was noticeably louder, meaning there is at an absolute minimum 3 dB of audio gain, and probably more like 6 dB. I didn't measure it but you can hear a difference with a controlled input.  I tried again at 0 dBm to overload the audio.  It was L-O-U-D with the earbuds on the table, but no howl, no squeal, and no feedback.

Tip:  Solder R5 into place from the bottom of the board.  It's easier to get to it and it won't slide down through because its already secured by gravity.  If you are building for the first time it really keeps R5 out of the way of the pushbutton switch standoffs.

72,

Chas - NK8O

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