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From: gandrews@netcom.COM (Greg Andrews)
Newsgroups: comp.dcom.modems
Subject: Re: Telebit modem power level
Summary: The power level is a negative number.
Message-ID: <1991Jun18.045058.5805@netcom.COM>
Date: 18 Jun 91 04:50:58 GMT
References: <873@wrangler.WLK.COM>
Distribution: na
Organization: Netcom - Online Communication Services  UNIX System {408 241-9760 guest}
Lines: 28

In article <873@wrangler.WLK.COM> bill@wrangler.WLK.COM (Bill Kennedy) writes:
>
>Here's my question.  Page E-1 of the T-1600 FM (I'm going to start with
>the T-1600 because it's already plugged into everything) starts its table
>with a power limit of 0.0 dBm, resistor value of 6.65K.  The TB+ FM, same
>page also starts at 0.0dBm, different value.  
>

Yes, the modems have different circuitry driving the telephone line, so
they use a different value resistor to achieve the same output power.

>
>  [....]
>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?  
>

They're negative numbers, so the larger the number, the softer the signal.
0 dBm is the loudest, -15 dBm is the softest.  You want to go softer, so
you want the resistor values associated with -10 dBm, -12 dBm, etc.


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 |  Greg Andrews   |       UUCP: {apple,amdahl,claris}!netcom!gandrews    |
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