Sine Systems silence sense

[HadYourPhil]

The suggested circuit for a silense sensor shown in the Sine Systems book (alliteration city!) uses 470mf caps as the "time constant" for sensing. Does anyone know the approximate time that gives? I am looking to build several of these and would like about a minute or so before triggering.

(page 4-3 in the manual)

 

[frankberry]

Without the manual and the resistor values associated with the timing circuit, it's impossible to answer your question.
Why not build one and adjust the capacitor value to get the delay that you require?

 

[HadYourPhil]

Excuuse me! I was just hoping someone might've been there before...
It uses a couple of 470 uf caps across the rectified audio: Audio in on the left, one side of the audio goes to the C1-C2 connection. The caps are (from top to bottom) + - + -, and D1 and D2 are polarized D1+, D2 -.

-----470 0hm--l--D1---l---- +
l C1
---------------------- l
l l
l
l C2
l--D2----l--- -

 

[ChiefEngineer]

The Sine unit book indicates the time. It is online at the Sine site. It is adjustable however. From several minutes as it ships to about 15 seconds where I set it.

In the past building a delay unit has involved capacitors across a relay coil that take some time to charge. Unfortunately it has always been experimental. Potter Brumfield sells some inexpensive time delay relays also. Another option?

 

[HadYourPhil]

That's strange. I had already downloaded the book (that's where the circuit came from) but the page this info is on, 4.3, doesn't give a time constant. Are you looking in a different/better book? Mine is RFC-1/B book.

 

[BobOnTheJob]

I have one of these across the 600 ohm output of a PCL 6000 STL receiver (wish all composite receivers had an always active 600 ohm output). It feeds an input channel on the RFC1/B. The delay can be varied by setting the low limit on the channel...the lower the limit before it alarms, the longer the time constant. It's been years since I built it, but it seems it takes 20 seconds or so in my application.

 

[HadYourPhil]

With the sloppy audio I have to deal with, I think I'd be more comfortable with 30-40 seconds.
Oh, for the days of an actual warm body in the studio...

 

[HadYourPhil]

I built two of the circuits, and as built with 470 uf capacitors, you get about a minute before alarm. 1000uf is two minutes. That's what I ended up using.

 

[Bengalsfan]

I have one of these across the 600 ohm output of a PCL 6000 STL receiver (wish all composite receivers had an always active 600 ohm output). It feeds an input channel on the RFC1/B. The delay can be varied by setting the low limit on the channel...the lower the limit before it alarms, the longer the time constant. It's been years since I built it, but it seems it takes 20 seconds or so in my application.

I have done something like that but using the audio out of a mod monitor. rectify the audio to a DC signal and put it on one of the Sine channels. Then calibrate the Sine to when that DC level drops below a trigger point, it fires an alarm.

 

[BobOnTheJob]

Goes to show how great these people are...they offer a silence sensor product and then tell you how to avoid buying it using $4 in parts.

 

[mbrg]

But if you buy from them you get a Goo Goo Cluster candy bar shipped with your item (better than bswusa's Almond Roca..). I've built from the book and bought their available versions of Silence Sense and Temp Monitor....homebrew works okay by setting the low limits and rules, but you get what you pay for.

 

[bossbill]

Sorry dude, but Almond Roca beats Goo Goo Cluster any day.

 

[alleo]

Re: Sine Systems RFC-1 B wont hang up the line ?

I heard the repair ICs are comeing from Jemco but what parts are cuseing the troub as I don't have dig for this yet but it will some time answ it just dosn't now that I'm 640 miles away from it why wouldn't it stop answ the phone while i was by it .................Allen