Mercury 1101 tube tester.

Discussion in 'Amp Tech Center' started by BobbyZ, Apr 27, 2016.

  1. BobbyZ

    BobbyZ Doctor of Teleocity

    Posts:
    12,369
    Joined:
    Jan 12, 2011
    Location:
    Snellman MN
    I played with it a little yesterday. Left it with my friend that owns the music store and I ended up working there yesterday.
    So I tested some RCA 6L6s out of my SFSR and a pair of new JJ 6L6 (GT labels) all four test in the "good" range at a 55 on the 0-100 scale.
    I didn't get time to actually check them in the SFSR to see if they were the "matched" quartet the tester seemed to indicate. (pretty sure they're not)

    When I get the time I've got a bunch of 6L6s laying around. Got a pair of Mesa labled Sylvanias that I know are weak so we'll see what the tester reads on those. That pair in a SFTR turned it into a big Vibro Champ.
    (Last time I had the SFTR chassis out I went through all my old Sylvania 6L6s hoping to end up with a good quad. I got a pair.)
     
  2. Johnny Cache

    Johnny Cache Former Member

    Posts:
    1,809
    Joined:
    Mar 6, 2014
    Location:
    Oregon
    Yeah, matching tubes is another issue, current draw and such things most testers are not very good at measuring. But isn't it good to know your able to measure their strength and check them other things. I can see a big difference is strength of tubes and usually try to use tubes with close to the same strength. Searching old preamp tubes I found allot of OS good ones from other devices I keep on hand for future use. Have fun!
     
  3. ranjam

    ranjam Tele-Holic

    Posts:
    642
    Joined:
    Dec 29, 2015
    Location:
    Canada
    I have owned and played with a lot of tube testers over the years. While they are kind of an over priced Ouija board, you can do things with them. You own a Bias Probe, right? If not, why not? Now use that Bias Probe in your tube tester to very roughly match some output tubes. Better than nothing. Of course the line voltage is rectified for the B+ in your tester, so you get maybe +150VDC on the plates, which won't translate well when put into your amp with +450VDC or +500VDC on the plates. But it is something that will indicate how the tubes tracks. I still check the current draw in the amp, and I actually believe I learn a little about the tube I am trying to make work in my amp.
    Sometimes I leave my Bias probe in the amp and watch the tube drift. Rather than do that, I can 'warm up' the tube in a tester, as others are being tested in the amp. Yep, it's involved, a time waster, and not very productive (as the best tester is still the amp), but something to do, and hopefully learn about your amp, the tube, the tester, everything. Eventually you get it down to an efficient science.
    Have fun, and get a better tester if the money and timing situation are right. Hit those ham swap meets. Good luck.
     
  4. Cjl77

    Cjl77 Tele-Meister

    Posts:
    420
    Joined:
    Nov 12, 2013
    Location:
    lake charles ,La
    I'm with silverface on this.
    What a tube does and reads at 150 volts is a whole lot different than at 450 volts.
    I have a home made set up I use. It's my bench power supply with basically a mock up amplifier mounted on a piece of plywood. Nothing fancy, but it runs tubes at real world voltages. That's all difference in my opinion. Good or bad isn't really a test.
     
  5. robrob

    robrob Poster Extraordinaire Ad Free Member

    Posts:
    7,626
    Joined:
    Dec 29, 2012
    Location:
    United States
    I have a tester in my shop and it looks cool but I haven't actually used it since I tried it out the day UPS delivered it.

    The best way to test power tubes for balance is to put them in an amp and bias it. Then swap the tubes in their sockets and see how much of the bias difference was due to the circuit, not the tubes.
     
  6. BobbyZ

    BobbyZ Doctor of Teleocity

    Posts:
    12,369
    Joined:
    Jan 12, 2011
    Location:
    Snellman MN
    I'm going to a hamfest next week but I won't buy another tester unless it's a real nice one and dirt cheap. This one is fine for me. Just to sort out the completely dead or shorted ones. The rest I'll do in the amp like I always have.
     
  7. keithcc

    keithcc Tele-Meister

    Posts:
    318
    Joined:
    Oct 20, 2009
    Location:
    Tulsa
    Real nice ones and dirt cheap do not go together.

    The olde phart hams have found out that the stuff of interest to audiophools and guitar geeks is Big Money. What goes to the hamfest is the stuff they don't want, unless he has went \SK (died) and the family takes it to the fest or lets his repeater club do it instead of dumpstering it all.

    The definitive book on tube testers:

    http://www.amazon.com/Tube-Testers-Classic-Electronic-Test/dp/1886606145
     
  8. BobbyZ

    BobbyZ Doctor of Teleocity

    Posts:
    12,369
    Joined:
    Jan 12, 2011
    Location:
    Snellman MN
    I missed the hamfest last weekend, my brother flew home. I was thinking that was this weekend.

    No biggy I would've just bought a bunch of crap anyways. :)

    Probably would've seen the same tube testers there I saw at the last one. Cut power cords and no manuals.
     
  9. cap47

    cap47 Tele-Holic

    Posts:
    530
    Joined:
    Jul 27, 2014
    Location:
    bushnell, fl
    Just because you've heard countless forum Experts?? say you need 400V doesn't make it fact! I would easily justify $100 if I saw a tester like that one with manual.
     
  10. Tele wacker

    Tele wacker Tele-Holic

    Posts:
    663
    Joined:
    Jun 15, 2009
    Location:
    Wichita is nice.
    I have used a little Sencore emissions tester for years and it serves me well. If the tubes test "strong", has good emissions, no grid leakage and no shorts, it is usually ok in an amp.
    I do agree that the bigger tube tester are better because they perform more tests on a tube. I have 2 of the bigger tube testers but the little Sencore is really handy.
     
    BobbyZ likes this.
IMPORTANT: Treat everyone here with respect, no matter how difficult!
No sex, drug, political, religion or hate discussion permitted here.


  1. This site uses cookies to help personalise content, tailor your experience and to keep you logged in if you register.
    By continuing to use this site, you are consenting to our use of cookies.