home *** CD-ROM | disk | FTP | other *** search
- Xref: sparky comp.sys.mac:277 comp.sys.mac.comm:8744 comp.sys.mac.hardware:16664
- Path: sparky!uunet!usc!elroy.jpl.nasa.gov!decwrl!bu.edu!Shiva.COM!chris
- From: chris@Shiva.COM (Chris Outzen)
- Newsgroups: comp.sys.mac,comp.sys.mac.comm,comp.sys.mac.hardware
- Subject: Re: Shiva 9600 v.32 NetModem needs fixed! Help!
- Message-ID: <1992Sep7.151533.14889@Shiva.COM>
- Date: 7 Sep 92 15:15:33 GMT
- References: <1992Aug27.222807.13917@sequent.com> <1992Sep4.065714.2381@lna.oz.au>
- Followup-To: comp.sys.mac
- Organization: Shiva Corporation, Cambridge, Ma, USA
- Lines: 24
-
- In article <1992Sep4.065714.2381@lna.oz.au> randy@lna.oz.au (Randolph CHRISTOPHERS) writes:
- >In article <1992Aug27.222807.13917@sequent.com> dwightj@sequent.com (Dwight Johnson) writes:
- >>I need to know how to fix our NetModem. Shiva wants over $250 to even
- >>look at it. I think it should be a one or two component replace job.
- >>
- >>..... I checked to 7805 chip inside. It maintains 25VDC
- >>input and 5VDC output even after the modem dies. It is really hot though.
- >>
- >Hooly dooly, thats a 20V difference. I don't think 7805's are meant for
- >that sort of torture (usually a DC input of less than 10V is OK). Little
- >wonder its cooking.
- >
- >Randy.
-
- There most be something wrong with your wall-mount transformer. It should
- have an output of 9V AC. This 9V AC is put through a full-wave rectifer and
- then used as the input to the voltage regulator. If you are see 20V DC at the
- input something is wrong. You should check the output of the wall-mount.
- F.Y.I. The regulator input should be somewhere about 9-10V DC depending on the
- line voltage.
-
- Chris Outzen
- Manager Hardware Development
- Shiva Corp
-