> Duane Hall <[EMAIL PROTECTED]> wrote: > I disagree with your above statement. The DHE voter is not > "a rectified hf noise circuit".
Well... maybe the hf noise label is not really 100% right. What I was trying to most point out is that it's not a true signal to noise voter circuit vs something like a Motorola or GE circuit. . > The Doug Hall Electronics 4RV and 4RV/2 Voters use a log amp > and peak valley circuits. There is an ac amplifier, might be a log layout but the following circuit is a standard percision rectifier. I never bothered to run audio through it to see if and where it might be audio spectral focused but it looks like a plain jane audio op-amp percision rectifier circuit to me. Call me silly but I don't see anything obvious in the circuit picking noise vs signal. > It is a relative comparator between channels so the output is > not a S/N value, Yep, it looks to be only a comparitor of the channel rectifier circuits against the other channels via a reference bus. One of the reasons why levels are so critical... loud voice audio in a not so well level set-up system can be voted-off same as noise. > but the comparison is based on S/N ratio. > Looking at the envelope of the audio, the peaks are the > signal, the valley is the noise floor. Signal to Noise. Well... isn't the percision rectifier after the log amp pretty much changing whatever ac signal it sees to rectified dc? It doesn't seem to have any circuit around it that's frequency seletive other than maybe an rc time constant before the rect. > You may be confusing the DHE voter with the LDG. My > understanding of the circuitry in the magazine article > (that the LDG was based on) is that it > uses rectified high freq noise. >From a brief glance they looked similar... but who knows. I might be out to lunch again and need to review my notes. Then again... > Early DHE voter production runs used thumbwheel pots, and > that made the level settings a little touchy. It sure is/was... > To the person who is looking for a 4RV manual from 1987, get > me your mailing address. I'll be glad to send you a copy. > Duane Hall, AB8QU > Doug Hall Electronics You folks have always been great about customer support... You should start making the RBI again... hint, hint. cheers, skipp
