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---------- Original Message ----------

From: John <jhaserick84@...>

To: [email protected], Burt K6OQK <biwa@...>

Date: 10/25/2022 8:38 PM

Subject: Re: [repeater-builder] QUANTAR VHF Audio Interface...

Yes, Burt, I also agree with that concept because it is better in those circumstances of low initial audio and to me it also makes sense to increase intelligibility when you are receiving noise on the repeater.? It does usually reduce the highs from them being selectively clipped, so the question is how do you boost the highs back when the clipping is done on pre-emphasized audio where flat audio is defined by the same voltage at the clipper when the input frequency is swept from lowest to highest frequency at the same input deviation? By adding high frequency boost after the clipper, and then more low pass filtering? Possibly easier and better to just eliminate the pre-emphasis components before the clipper, and add comparable pre-emphasis after the clipper so a little audio compression without reducing highs and still the same low pass roll-off. There must be a way to configure Kevin's clipper /filter to achieve this result.

To my thinking, the advantage from having no repeater compression or clipping is when you want to repeat a repeat times X in analog so as to not keeping adding background noise or distortion each time, at least on the link radios if a quiet link path. Guess that is one big advantage of digital repeaters?

John

On 10/25/2022 4:47 PM Burt K6OQK <biwa@...> wrote:

John,

I personally do not believe in the 5 kHz in and 5 kHz out thinking.? A part of the problem is that stations with low deviation will come through with low deviation and those with high deviation can hit the transmitter's limiter too hard.? Some believe that it's the responsibility of those stations to correct their deviation, and learn to use correct mic technique. My experience in that area has proven to be: Good Luck!

Please understand, I don't mean to be talking at you, but just intellectualizing with you...

To my way of thinking, a repeater is not a piece of test equipment to be used as a deviation tester.? It's a contraption to improve / enable communications.? Proper processing also protects the transmitter and adjacent channel spectrum in a less destructive way.? Anything I can do to make it simple, reliable, and pleasant, is a plus.? That's why I have always used appropriate audio processing on my repeaters.? I've gotten arguments from the unwashed telling me that it brings up the noise on the incoming signal. Well, yes, that's true, but you're going to have to turn up the volume at the user's end if you want to hear those stations anyway.? When you do that you are not only bringing up the noise heard by the repeater, but also any noise between and the repeater.? Having to turn the volume up and down while listening to a repeater gets tiring after a while.

For what it's worth,

Burt, K6OQK