Thanks John -- You are the second one to suggest them. Talon is the deal for sure. I ordered two of these parts. Fluke used them in a lot of gear. Have any volt-nuts modified the chopper system of the 343A to reduce parts count and improve stability? Seems like a good place for an LT1150, OPA627 or some such to improve overall performance.... Dick Moore On Nov 7, 2012, at 4:00 AM, volt-nuts-request@febo.com wrote: > Message: 1 > Date: Tue, 6 Nov 2012 14:10:16 +0000 > From: John Lofgren <jlofgren@lsr.com> > To: Discussion of precise voltage measurement <volt-nuts@febo.com> > Subject: Re: [volt-nuts] Fluke 343A part > Message-ID: > <5544E52D608067489823B4AED0BB6B570B0B7491@Exchange2010.lsr.local> > Content-Type: text/plain; charset="us-ascii" > > Talon Electronics shows a Fluke FP226043 as the replacement for the MEM556C. They have 48 in stock at $5.12 with no minimum order. > http://www.talonix.com/shop/item.aspx?itemid=3978 > > -John > > > -----Original Message----- > From: volt-nuts-bounces@febo.com [mailto:volt-nuts-bounces@febo.com] On Behalf Of Dick > Sent: Tuesday, November 06, 2012 1:06 AM > To: volt-nuts@febo.com > Subject: [volt-nuts] Fluke 343A part > > I picked up a fairly new Fluke 343A and it appears that Q39, MEM556C p-chan. enhancement-mode MOS-FET is shorted. This part seems to be unobtanium unless you are named Romney, Gates, or Walton. Any suggestions on a replacement or an alternative method? This part is the input signal chopper transistor, driven by a multivibrator.

I've used Talon as well, their prices are usually only affordable by taxpayers via their respective governments but like this one they have surprised me in the past. One time they sent me the wrong part and they sent me the replacement and asked at my convience to send the other one back On Wed, Nov 7, 2012 at 11:36 AM, Dick <richiem5683@gmail.com> wrote: > Thanks John -- You are the second one to suggest them. Talon is the deal for sure. I ordered two of these parts. Fluke used them in a lot of gear. > > Have any volt-nuts modified the chopper system of the 343A to reduce parts count and improve stability? Seems like a good place for an LT1150, OPA627 or some such to improve overall performance.... > > Dick Moore > > > On Nov 7, 2012, at 4:00 AM, volt-nuts-request@febo.com wrote: > >> Message: 1 >> Date: Tue, 6 Nov 2012 14:10:16 +0000 >> From: John Lofgren <jlofgren@lsr.com> >> To: Discussion of precise voltage measurement <volt-nuts@febo.com> >> Subject: Re: [volt-nuts] Fluke 343A part >> Message-ID: >> <5544E52D608067489823B4AED0BB6B570B0B7491@Exchange2010.lsr.local> >> Content-Type: text/plain; charset="us-ascii" >> >> Talon Electronics shows a Fluke FP226043 as the replacement for the MEM556C. They have 48 in stock at $5.12 with no minimum order. >> http://www.talonix.com/shop/item.aspx?itemid=3978 >> >> -John >> >> >> -----Original Message----- >> From: volt-nuts-bounces@febo.com [mailto:volt-nuts-bounces@febo.com] On Behalf Of Dick >> Sent: Tuesday, November 06, 2012 1:06 AM >> To: volt-nuts@febo.com >> Subject: [volt-nuts] Fluke 343A part >> >> I picked up a fairly new Fluke 343A and it appears that Q39, MEM556C p-chan. enhancement-mode MOS-FET is shorted. This part seems to be unobtanium unless you are named Romney, Gates, or Walton. Any suggestions on a replacement or an alternative method? This part is the input signal chopper transistor, driven by a multivibrator. > > > _______________________________________________ > volt-nuts mailing list -- volt-nuts@febo.com > To unsubscribe, go to https://www.febo.com/cgi-bin/mailman/listinfo/volt-nuts > and follow the instructions there.