The basic technology if anybody is interested: http://www.logwell.com/tech/CCL/index.html
and the meter itself (minus the comparator part): http://www.logwell.com/tech/CCL/shooting_CCL_amps.html http://www.logwell.com/schematics/shooting_CCL_schematics.html Syd ----- Original Message ----- To: "Multiple recipients of list CHIPDIR-L" <[email protected]> Sent: Sunday, September 18, 2005 4:04 PM >>> 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). > -- 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).
