Path: utzoo!utgpu!news-server.csri.toronto.edu!rpi!zaphod.mps.ohio-state.edu!wuarchive!uunet!pilchuck!ssc!tad
From: tad@ssc.UUCP (Tad Cook)
Newsgroups: comp.dcom.modems
Subject: Re: Telebit modem power level
Summary: - dbm levels
Message-ID: <1217@ssc.UUCP>
Date: 24 Jun 91 03:51:25 GMT
References: <873@wrangler.WLK.COM>
Distribution: na
Organization: very little
Lines: 33

In article <873@wrangler.WLK.COM>, bill@wrangler.WLK.COM (Bill Kennedy) writes:
> 
> Hmm, I seem to have promised a question a few paragraphs early...  It would
> seem to me that the T-1600 is set just like the TB+ in that they both have
> resistors for a -9 dBm power limit.  The Telebit tables range from 0dBm to
> -15dBm and I have the right resistors to cover that range.  The problem I am
> trying to solve is that the modem on this end is pushing too much energy into
> the line, I was able to significantly improve my S/N ratio by turning the
> cellular volume down as far as it would go.  So which way do I go?  Do I
> progress from -9dBm towards 0 dBm or towards -15dBm? 


 
If the output level is now -9 dbm, then going to -11 dbm or -12 dbm
would be a lower level.
 
The actual voltage output is referenced to 1 mw on a 600 ohm
load, which is about 775 mv (.775 volts) for 0 dbm.  For -9 dbm,
it is about 275 mv.  -12 dbm is about 195 mv.  -15 dbm is about
138 mv.



Tad Cook
Seattle, WA
Packet: KT7H @ N7DUO.WA.USA.NA
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