Got a new multimeter

Discussion in 'General Electronics Chat' started by tom66, Feb 12, 2011.

  1. tom66

    Thread Starter Senior Member

    May 9, 2009
    First, a little rant: This meter was $99 + $35 shipping, which was a pretty good deal. That made it around £85. But because I ordered it from the USA (couldn't find it *anywhere* in the UK) I had to pay £23 in customs fees / VAT. :( That made it a bit more expensive than I had originally intended.

    But, it is a nice meter. It's a BK Precision 2709B. True RMS, 6,600 counts, 0.5% basic DC accuracy. Very good protection; two massive MOVs according to internal pictures, along with HRC fuses. Continuity mode is fast (<100ms) and latched (which is very good.) Most other ranges autorange very quickly. Capacitance is a bit slow, but does go up to 66mF, and it does let you range switch through it. It measures frequency, up to 66 MHz(!), which eliminates my need to buy a separate frequency counter, for now at least, as long as I don't need to measure very high frequencies.

    It's also got input jack detection. If you select a voltage range, but plug the probes into the current jacks, it beeps at you to alert you to this (very useful!) All ranges but AC/DC volts are protected to 500V; AC/DC goes to 750Vrms/1000V.

    I chose it mainly because Dave Jones (eevblog) highly recommended it.
  2. someonesdad

    Senior Member

    Jul 7, 2009
    On B&K's website, there's a link "Where to Buy" and they give a UK distributor:

    Company: Metrix Electronics Ltd
    City: Hampshire
    Country: United Kingdom
    Phone: 44 845 0343234

    If that one isn't current, an email or phone call to B&K might have uncovered another distributor near you.
    Last edited: Feb 12, 2011
  3. R!f@@

    AAC Fanatic!

    Apr 2, 2009
    Bk..I never heard of 'em..
  4. tom66

    Thread Starter Senior Member

    May 9, 2009
    Dammit, if I'd known that... anyway, I've bought it now.
  5. thatoneguy

    AAC Fanatic!

    Feb 19, 2009
    The frequency bandwidth is impressive! Price isn't too bad either.

    What is the shortest duration will the min/max/avg function catch? 1mS 10mS?
  6. SgtWookie


    Jul 17, 2007
    Just some recollections....
    One of B&K Precision's early products was a TV picture tube rejuvenator. I remember reading about those things back in the 60's. The basic idea was to get the cathode really hot by increasing the heater voltage temporarily, and then giving the cathode a HV blast that would strip a layer of the cathode material off. This was far better than methods that were offered by other manufacturers.

    I remember a "picture tube brightener" which you plugged in between the chassis harness and the picture tube base; my Dad bought one in the early 60's for our big DuMont black & white TV that was getting dark. I'm sure what it contained was a transformer to boost the voltage supplied to the heater filaments, increasing the emissions from the cathode.

    In those days, when you turned off a TV, the picture shrunk to an eerie white dot that remained for a long time in the center of the screen, which I would watch with fascination; I had no clue that I was being exposed to X-ray radiation. More modern CRT TV's had circuitry to prevent such emissions. Nowadays, you can't even buy a CRT TV, they are all LCD or LED panels.
  7. tom66

    Thread Starter Senior Member

    May 9, 2009
    I believe it is limited to the sample rate, so only 333ms (3 Hz sampling.)

    I also know now how I missed that supplier - I went to BK's site, typed in "2709B" to search for distributors, and got this list:

    The closest one was Sefram, but they had no pricing. All the others were US based.

    SgtWookie, your story brings an interesting point; why do modern CRT TVs flash when you turn them off? I remember once having a TV which did not do this. It was a sales point, I think, but I don't really know why...

    To test the frequency counter, I can use my dsPIC33F which should be clocked at 36.85 MHz +/-1%, or my PIC24F, clocked at 14.7456 MHz +/-0.005%.
  8. SgtWookie


    Jul 17, 2007
    Can't tell you offhand.
  9. marshallf3

    Well-Known Member

    Jul 26, 2010
    Hard to beat a good B&K
  10. debe

    Well-Known Member

    Sep 21, 2010
    Hi wookie, I still have one of those picture tube brighteners. Here in Australia they were made by Arlec, was a small 240V to taped outputs of 6.3/7.5/8.5/9.5V ac @ 1Amp. they certainly extended a BW picture tube, then that was back in the 60s.