My trusty old Russky meter died and I can't be sans analog meter for long. Must be cheap and simple because they get dropped, crushed, snatched, whatever. Has anyone used the HM-102S while in the service? https://www.amazon.com/SOLTEC-HM-102S-Analog-Multimeter-VOLTS/dp/B01M1ETSF9 Why do these need a 9V battery? At 20k/V input impedance that just doesn't make sense. -- Regards, Joerg http://www.analogconsultants.com/
Analog meters: Why do they need a 9V battery?
Started by ●March 14, 2017
Reply by ●March 14, 20172017-03-14
That meter also measures resistance. It needs the battery so it can source current to measure the resistance. V/A measurements shouldn't need the battery to operate on their own. Ray Otwell On Tue, 14 Mar 2017 13:34:39 -0700, Joerg <news@analogconsultants.com> wrote:>My trusty old Russky meter died and I can't be sans analog meter for >long. Must be cheap and simple because they get dropped, crushed, >snatched, whatever. Has anyone used the HM-102S while in the service? > >https://www.amazon.com/SOLTEC-HM-102S-Analog-Multimeter-VOLTS/dp/B01M1ETSF9 > >Why do these need a 9V battery? At 20k/V input impedance that just >doesn't make sense.
Reply by ●March 14, 20172017-03-14
On Tuesday, March 14, 2017 at 4:34:36 PM UTC-4, Joerg wrote:> My trusty old Russky meter died and I can't be sans analog meter for > long. Must be cheap and simple because they get dropped, crushed, > snatched, whatever. Has anyone used the HM-102S while in the service? > > https://www.amazon.com/SOLTEC-HM-102S-Analog-Multimeter-VOLTS/dp/B01M1ETSF9 > > Why do these need a 9V battery? At 20k/V input impedance that just > doesn't make sense. > > -- > Regards, Joerg > > http://www.analogconsultants.com/Perhaps for reading high (Meg) Ohms.
Reply by ●March 14, 20172017-03-14
On 2017-03-14 13:51, Ray Otwell wrote:> That meter also measures resistance. It needs the battery so it can > source current to measure the resistance. V/A measurements shouldn't > need the battery to operate on their own. >Yes, but it also needs two AA cells (most meters only need one) and that ought to be enough. This meter requires a whopping three batteries, two AA and one 9V. If for some reason they use 9V for the highest ohms range that would be ok because it's no big deal when that doesn't work for long.> Ray Otwell > > > > On Tue, 14 Mar 2017 13:34:39 -0700, Joerg <news@analogconsultants.com> > wrote: > >> My trusty old Russky meter died and I can't be sans analog meter for >> long. Must be cheap and simple because they get dropped, crushed, >> snatched, whatever. Has anyone used the HM-102S while in the service? >> >> https://www.amazon.com/SOLTEC-HM-102S-Analog-Multimeter-VOLTS/dp/B01M1ETSF9 >> >> Why do these need a 9V battery? At 20k/V input impedance that just >> doesn't make sense.-- Regards, Joerg http://www.analogconsultants.com/
Reply by ●March 14, 20172017-03-14
On 2017-03-14 13:54, alan.yeager.2013@gmail.com wrote:> On Tuesday, March 14, 2017 at 4:34:36 PM UTC-4, Joerg wrote: >> My trusty old Russky meter died and I can't be sans analog meter for >> long. Must be cheap and simple because they get dropped, crushed, >> snatched, whatever. Has anyone used the HM-102S while in the service? >> >> https://www.amazon.com/SOLTEC-HM-102S-Analog-Multimeter-VOLTS/dp/B01M1ETSF9 >> >> Why do these need a 9V battery? At 20k/V input impedance that just >> doesn't make sense. >> >> -- >> Regards, Joerg >> >> http://www.analogconsultants.com/ > > Perhaps for reading high (Meg) Ohms. >Possible but still strange because the two AAs should be plenty for a meter with such a sensitive coil in it. -- Regards, Joerg http://www.analogconsultants.com/
Reply by ●March 14, 20172017-03-14
Joerg schrieb:> On 2017-03-14 13:54, alan.yeager.2013@gmail.com wrote:[...]>> Perhaps for reading high (Meg) Ohms.> Possible but still strange because the two AAs should be plenty for a > meter with such a sensitive coil in it.The meter has an Ohm x 10k range; the highest resistance mark on the Ohms scale is 20k: that corresponds to 200 MOhm. With a 9 V battery, the current through a 200 MOhm resistor will be 45 nA ... HTH Reinhard
Reply by ●March 14, 20172017-03-14
Oops. You're entirely right, I just looked and answered without thinking, and without considering that most everyone on here knows FAR more than I do. RO On Tue, 14 Mar 2017 13:57:44 -0700, Joerg <news@analogconsultants.com> wrote:>On 2017-03-14 13:51, Ray Otwell wrote: >> That meter also measures resistance. It needs the battery so it can >> source current to measure the resistance. V/A measurements shouldn't >> need the battery to operate on their own. >> > >Yes, but it also needs two AA cells (most meters only need one) and that >ought to be enough. This meter requires a whopping three batteries, two >AA and one 9V. > >If for some reason they use 9V for the highest ohms range that would be >ok because it's no big deal when that doesn't work for long. > > > >> Ray Otwell >> >> >> >> On Tue, 14 Mar 2017 13:34:39 -0700, Joerg <news@analogconsultants.com> >> wrote: >> >>> My trusty old Russky meter died and I can't be sans analog meter for >>> long. Must be cheap and simple because they get dropped, crushed, >>> snatched, whatever. Has anyone used the HM-102S while in the service? >>> >>> https://www.amazon.com/SOLTEC-HM-102S-Analog-Multimeter-VOLTS/dp/B01M1ETSF9 >>> >>> Why do these need a 9V battery? At 20k/V input impedance that just >>> doesn't make sense.
Reply by ●March 14, 20172017-03-14
Yag... Sorry for the wrong nym, there. On Tue, 14 Mar 2017 17:37:55 -0400, Gone Postal <gone_postal@it.doesn't.exist> wrote:>Oops. > >You're entirely right, I just looked and answered without thinking, >and without considering that most everyone on here knows FAR more than >I do. > >RO > > >On Tue, 14 Mar 2017 13:57:44 -0700, Joerg <news@analogconsultants.com> >wrote: > >>On 2017-03-14 13:51, Ray Otwell wrote: >>> That meter also measures resistance. It needs the battery so it can >>> source current to measure the resistance. V/A measurements shouldn't >>> need the battery to operate on their own. >>> >> >>Yes, but it also needs two AA cells (most meters only need one) and that >>ought to be enough. This meter requires a whopping three batteries, two >>AA and one 9V. >> >>If for some reason they use 9V for the highest ohms range that would be >>ok because it's no big deal when that doesn't work for long. >> >> >> >>> Ray Otwell >>> >>> >>> >>> On Tue, 14 Mar 2017 13:34:39 -0700, Joerg <news@analogconsultants.com> >>> wrote: >>> >>>> My trusty old Russky meter died and I can't be sans analog meter for >>>> long. Must be cheap and simple because they get dropped, crushed, >>>> snatched, whatever. Has anyone used the HM-102S while in the service? >>>> >>>> https://www.amazon.com/SOLTEC-HM-102S-Analog-Multimeter-VOLTS/dp/B01M1ETSF9 >>>> >>>> Why do these need a 9V battery? At 20k/V input impedance that just >>>> doesn't make sense.
Reply by ●March 14, 20172017-03-14
On 2017-03-14 14:36, Reinhard Zwirner wrote:> Joerg schrieb: >> On 2017-03-14 13:54, alan.yeager.2013@gmail.com wrote: > > [...] >>> Perhaps for reading high (Meg) Ohms. > >> Possible but still strange because the two AAs should be plenty for a >> meter with such a sensitive coil in it. > > The meter has an Ohm x 10k range; the highest resistance mark on the > Ohms scale is 20k: that corresponds to 200 MOhm. With a 9 V battery, > the current through a 200 MOhm resistor will be 45 nA ... >Some of my previous meters were able to do this but if the 9V battery is only used for the highest resistance range that would be fine. I just want to be sure since I do not want any electronics in the way for DC measurements. I had a analog transistor voltmeter before and in the presence of pulsed RF it was about as fickle as DVMs are. It was so bad that I scrapped the thing. -- Regards, Joerg http://www.analogconsultants.com/
Reply by ●March 15, 20172017-03-15
Ray Otwell <ray(no space here)otwell(at)gmail(dot)com> wrote:>That meter also measures resistance. It needs the battery so it can >source current to measure the resistance. V/A measurements shouldn't >need the battery to operate on their own.If I don't need to measure resistors >100 k, 1.5V is sufficient. Diode test can have a need of higher voltages if one wants to test LEDs also. -- Dipl.-Inform(FH) Peter Heitzer, peter.heitzer@rz.uni-regensburg.de
