Hello Fabio, the rattling is ok, and as far as I remember, the behaviour was different depending on the range. Either the circuitry simply discharged the caps (rattling sound), or it even shut off the output completely, as if a short circuit occured. This is described in the manual, which you can find on the net. On your unit, I suspect the crowbar driver circuitry and/or sink supply to work incorrectly. Frank

Frank Stellmach <frank.stellmach@freenet.de> ha scritto: > Hello Fabio, > ... > > On your unit, I suspect the crowbar driver circuitry and/or sink > supply to work incorrectly. > > Frank Hello Frank, thank you, now I don't have time, but I opened the unit and saw a lot of dirt, this unit is old , the selectors plastic parts seem a little fragile and one was repaired in the past. when I have a little time I'll clean it and check the circuitry, I downloded the manual, the important is that the matched resistors and the voltage reference seem to be ok, the rest should be not hard to fix. Fabio. ---------------------------------------------------------------- This message was sent using IMP, the Internet Messaging Program.

Hi, Fabio, Also dont forget that the electroytics will be leaky with not being used for a while. After cleanng, try and leave it on overnight to reform them, unless it seems to be getting hot that is. M K > Date: Sat, 12 May 2012 09:08:14 +0200 > From: fabioeb@quipo.it > To: volt-nuts@febo.com > Subject: Re: [volt-nuts] Fluke 343 arrived, trip behaviour > > Frank Stellmach <frank.stellmach@freenet.de> ha scritto: > > > Hello Fabio, > > > ... > > > > On your unit, I suspect the crowbar driver circuitry and/or sink > > supply to work incorrectly. > > > > Frank > > Hello Frank, thank you, now I don't have time, but I opened > the unit and saw a lot of dirt, this unit is old , > the selectors plastic parts seem a little fragile and > one was repaired in the past. > when I have a little time I'll clean it and check the circuitry, > I downloded the manual, the important is that the matched resistors > and the voltage reference seem to be ok, the rest should be not hard to fix. > > Fabio. >

Another question for who opened these units before: my 343 main board is marked 341 3003, is the board shared between the two models? If I remember correctly in the schematics the differences on the mainboard should be some components values, is this correct? Fabio. m k <m1k3k1@hotmail.com> ha scritto: > > Hi, Fabio, > > Also dont forget that the electroytics will be leaky with not being > used for a while. After cleanng, try and leave it on overnight to > reform them, unless it seems to be getting hot that is. > > M K > >> Date: Sat, 12 May 2012 09:08:14 +0200 >> From: fabioeb@quipo.it >> To: volt-nuts@febo.com >> Subject: Re: [volt-nuts] Fluke 343 arrived, trip behaviour >> >> Frank Stellmach <frank.stellmach@freenet.de> ha scritto: >> >> > Hello Fabio, >> > >> ... >> > >> > On your unit, I suspect the crowbar driver circuitry and/or sink >> > supply to work incorrectly. >> > >> > Frank >> >> Hello Frank, thank you, now I don't have time, but I opened >> the unit and saw a lot of dirt, this unit is old , >> the selectors plastic parts seem a little fragile and >> one was repaired in the past. >> when I have a little time I'll clean it and check the circuitry, >> I downloded the manual, the important is that the matched resistors >> and the voltage reference seem to be ok, the rest should be not hard to fix. >> >> Fabio. >> > > > _______________________________________________ > 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. > ---------------------------------------------------------------- This message was sent using IMP, the Internet Messaging Program.

The 341A is a 343A with one fewer stage in the K-V divider. Otherwise it is electrically the same. Because the 343A has slightly better drift and noise characteristics, it is probable that it uses some parts that are selected. -Chuck Harris Fabio Eboli wrote: > Another question for who opened these units before: > my 343 main board is marked 341 3003, is the board shared > between the two models? > If I remember correctly in the schematics the differences > on the mainboard should be some components values, > is this correct? > > Fabio.