Path: utzoo!mnetor!tmsoft!torsqnt!lethe!yunexus!ists!helios.physics.utoronto.ca!news-server.csri.toronto.edu!bonnie.concordia.ca!uunet!hayes!tnixon
From: tnixon@hayes.uucp
Newsgroups: comp.dcom.modems
Subject: Re: Practical Peripherals 9600 ROM version 1.29
Message-ID: <3791.27c25401@hayes.uucp>
Date: 20 Feb 91 10:48:33 GMT
References: <4142@orbit.cts.com> <24586@netcom.COM> <39430@cup.portal.com>
Organization: Hayes Microcomputer Products, Norcross, GA
Lines: 31

In article <39430@cup.portal.com>, schuster@cup.portal.com (Michael
Alan Schuster) writes: 

>>Being a radio enthusiast, it's hard for me to expect too much from
>>a high-speed modem without _ANY_ RF shielding, and no grounding. It took
>>me a couple days to keep the VHF packet station from driving it nuts!
> 
> Oh, Gawd! both my ATI and USR modems have the main board practically encased
> in metal (or plasticized foil). NO shielding! Is there an FCC Class "-A"
> certification?

I'm quite certain the PP9600SA is FCC Part 15 Class B certified for 
use in residential areas.  It is _not_ always necessary to have 
sheilding to pass Part 15, since Part 15 regulates _emission_ of 
electromagnetic interference!  It is possible to properly design the 
modem so that separate metallic sheilding isn't necessary.  Part 15 
doesn't, however, regulate at all whether or not the product will be 
affected by outside interference coming INTO the modem; that's left 
entirely up to the product designer.  

I may be wrong (I haven't seen the inside of a PP9600SA myself), but 
if you look at the inside of the plastic case, you'll probably find 
that it is dull gray color.  This would be metallicized paint, which 
IS shielding.  It's not necessary to have foil or metal parts to 
keep the modem from emitting interference.

-- 
Toby Nixon, Principal Engineer    | Voice   +1-404-840-9200  Telex 151243420
Hayes Microcomputer Products Inc. | Fax     +1-404-447-0178  CIS   70271,404
P.O. Box 105203                   | UUCP uunet!hayes!tnixon  AT&T    !tnixon
Atlanta, Georgia  30348  USA      | Internet       hayes!tnixon@uunet.uu.net