>> This thing is a meter that shows when a casing collar locator (CCL) >> passes a coupling in an oil well. It is a simple amplifier and a >> microammeter that always runs off raw vehicle DC just fine. But the part >> that needs the bipolar supply is an auxiliary board that is a simple >> comparator circuit driving a Sonanlert annunciator when a collar is >> detected. >> >> This problem arises because the original manufacturer put one of those >> potted "brick" bipolar supplies in the gizmo that runs off mains line AC >> power (actually off of a generator or inverter in the truck). The way >> the thing is rigged, it is profoundly unsafe since explosives are >> dangling below the CCL. I have to get that line power out of the unit, >> hence the DC / DC converter. In the abscence of the comparator circuit, >> I would just run it on the vehicle 12 volt supply, but that dern >> comparator needs the bipolar supply. >> >> Sorry for not being more specific in the original post. >> >> Syd >> >> ----- Original Message ----- >> From: "Fred Townsend" <[EMAIL PROTECTED]> >> To: "Multiple recipients of list CHIPDIR-L" <[email protected]> >> Sent: Saturday, September 17, 2005 7:19 PM >> Subject: Re: Bipolar Power Supply >> >> >>>I have no way of determining what will or will not problem because you >>>have not defined the sensitivity of your application. 'Little circuit' >>>doesn't tell me much. However the converter scheme you describe is about >>>as good as it gets. I would make sure that primary and secondary grounds >>>are NOT connected together. Otherwise I would not expect a problem. >>> >>> Fred Townsend >>> >>> Syd H. Levine wrote: >>> >>>>I have a little circuit that runs off the 12 volt power supply in a >>>>vehicle. Part of the circuit needs a bipolar supply, and I was planning >>>>to use one of the cute little DC / DC converters to output maybe 5 watts >>>>off + and - 15 volt DC. The converter I have selected has a PI filter >>>>on the input, accepts a wide input range (8-18 Volts), and is regulated. >>>>My question is whether alternator hash will be a problem, Will I need a >>>>choke and capacitor on the front end of this gizmo like we used to put >>>>on car radios and the like? Or will the converter do its job OK with >>>>raw vehicle DC? >>>> >>>>Thanks in advance. >>>> >>>>Syd H. Levine >>>>AnaLog Services, Inc. >>>>Phone: 270-276-5671 >>>>Telefax: 270-276-5588 >>>>E-mail: [EMAIL PROTECTED] >>>>URL: www.logwell.com >>>> >>>> >>>> >>> >>> >>> >>> -- >>> Author: Fred Townsend >>> INET: [EMAIL PROTECTED] >>> >>> Fat City Hosting, San Diego, California -- http://www.fatcity.com >>> --------------------------------------------------------------------- >>> To REMOVE yourself from this mailing list, send an E-Mail message >>> to: [EMAIL PROTECTED] (note EXACT spelling of 'ListGuru') and in >>> the message BODY, include a line containing: UNSUB CHIPDIR-L >>> (or the name of mailing list you want to be removed from). You may >>> also send the HELP command for other information (like subscribing). >>> >> >
-- Author: Syd H. Levine INET: [EMAIL PROTECTED] Fat City Hosting, San Diego, California -- http://www.fatcity.com --------------------------------------------------------------------- To REMOVE yourself from this mailing list, send an E-Mail message to: [EMAIL PROTECTED] (note EXACT spelling of 'ListGuru') and in the message BODY, include a line containing: UNSUB CHIPDIR-L (or the name of mailing list you want to be removed from). You may also send the HELP command for other information (like subscribing).
