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    Tube Tester

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    Brap

    Posts : 83
    Join date : 2013-11-28
    Age : 61
    Location : Lisle, Illinois

    Tube Tester

    Post by Brap on Wed May 14, 2014 3:15 pm

    Looking for a decent tube tester for a variety of tubes. Pre-amp tubes to EL-34, KT-66 and newly released EL-509's from JJ. Having the ability to test 2A3's (4 pin) would be a bonus.

    Any ideas out there???

    MontanaWay

    Posts : 781
    Join date : 2014-02-06
    Age : 58
    Location : Brookings, Oregon

    Re: Tube Tester

    Post by MontanaWay on Wed May 14, 2014 7:28 pm

    Hickok seem to be the ants pants in tube testers.
    I myself have bought a 600A tester, should be arriving next week.

    One of the things that I have learned about testers in general by reading countless posts etc is that they are finicky and need to stay calibrated in order to give you the best and most accurate results.
    From what I have read, calibrating is not hugely difficult but a somewhat lengthy process, there are some excellent write ups on 'how to', I would also advise you to buy a 'calibration tube', usually 6L6, these are normally NOS and have been tested on calibrated testers, some suppliers almost certify these tubes, each of these calibration tubes come with a complete set of measurements, which you then compare against your own tester to see how well it is doing.
    There are some other components you should obtain to check and calibrate your tester.
    Regular maintenance and calibration is also recommended.
    Buying one, unless stated that is has been professionally calibrated etc., can be a bit of a hit and miss and can be costly, or you can pay close to $200 to have your tester professionally calibrated.
    The 600A I purchased was supposedly recently calibrated, I did buy it from a tube and test gear suppler, but still, I have purchased a calibrated 6L6 plus some other gear so that I can do my own calibration, I will also probably do a minor rebuild, such as replacing caps and checking resistor values etc., to ensure that when I do start to check tubes, the results I get are as close to the true condition of the tested tube/s.

    sKiZo

    Posts : 1308
    Join date : 2013-04-01
    Location : Michigan USA

    Re: Tube Tester

    Post by sKiZo on Wed May 14, 2014 8:29 pm

    Here's mine ... garage sale find from an old hammer ...



    May not look like much, but it's got the latest rolls and expansions.
    Does everything I need it to do anyway.

    Some of these things were real works of art inside ...



    Check out all the point to point, laced bundles, open contacts, oh oh oh ... wait ... let me go get a towel!




    MontanaWay

    Posts : 781
    Join date : 2014-02-06
    Age : 58
    Location : Brookings, Oregon

    Re: Tube Tester

    Post by MontanaWay on Wed May 14, 2014 8:38 pm

    thats another thing I meant to say, charts. Some are quite old, so make sure, they are at least 1961/2 onwards. Repro charts are available online to suit most chart using tube testers.
    Also, make sure that the tester you are thinking of buying has 9 & 7 pin mini sockets, some of the early ones do not. You can always get adapters, but they are not as readily available from what I've seen.

    Here is a good write up and testers, http://www.tubewizard.com/recommended_Hickok_testers.htm
    http://padgett.performanceresearch.us/tester/laterh.htm#580

    Tiziano73

    Posts : 29
    Join date : 2012-09-11
    Location : Italy

    Re: Tube Tester

    Post by Tiziano73 on Thu May 15, 2014 6:57 am

    Hi

    to test and match my tubes i use an Hickok 750 and a Tube Imp Digital Tester with a socket adapter.
    For phase/splitter tubes i prefer to select my matched pair with Tube Imp for Gm (pentode section) and Mu & Ia (triode section) for a balanced pair.
    For 12AX7 tubes i match them again with Tube Imp for Mu and Ra (Ra=Mu/Gm).
    I use Hickok for Gas, Shorts, Microphonics & Gm of all my tubes and it can also test rectifier for current.

    I hope this helps.

    BR

    Tiziano

    sailor

    Posts : 269
    Join date : 2011-04-04

    Re: Tube Tester

    Post by sailor on Thu May 15, 2014 9:17 pm

    Hi Brap, sailor here, The problem with all of the older American testers is none will list the JJ EL509. Because it's a lot newer tube than the testers. The  JJ EL509 has the same pin out as the 6550 family but requires a much higher bios voltage than that group of tubes. If the the bios is KT88 level the life of the tube will be very short. If the tester will allow you to adjust all of the parameters and will test  all of the tubes including the old 300B group. You should be able to set the necessary settings on the tester. I would ask Bruce at what settings he thinks the tube should be tested. Then look for a tester that will allow you to make the required adjustments. Of course I think you know where there is a schematic to build a tester or test and tube analyzer  from scratch. Hope that makes sense.

    sKiZo

    Posts : 1308
    Join date : 2013-04-01
    Location : Michigan USA

    Re: Tube Tester

    Post by sKiZo on Fri May 16, 2014 1:12 am

    My understanding is that KT88's and 6550's should use the same settings you'd use for a 6CA7, and those should be available on most any tester.

    Ditto for the EL34's and equivalents ...

    Also worth mentioning, a lot of the lists show number first, so you MAY have them listed, but bass ackwards, as in 88KT ...

    ~~~

    Wondering about the KT120's ... haven't found anything specific, but I imagine you could do macro tests on those using the same settings.

    sailor

    Posts : 269
    Join date : 2011-04-04

    Re: Tube Tester

    Post by sailor on Fri May 16, 2014 9:53 am

    Hi skizo, were these comments for me? If so it is the JJ EL509 that uses a much higher bios voltage and only JJ has ever made this tube. It is not the same as the old EL509 or it's American cousin the 6KG6 that may be on some tube testers which has a top cap.

    Brap

    Posts : 83
    Join date : 2013-11-28
    Age : 61
    Location : Lisle, Illinois

    Re: Tube Tester

    Post by Brap on Fri May 16, 2014 10:10 am

    Thanks guys for all the feedback on this topic. I guess I will just finish up the SOB and put the tubes in, flip the switch and close my eyes! JK. Per previous discussions, purchased 10 EL509's since there was some comments that there could be QC issues and that possibly 1 - 2 out of 8 could go south in the early stages. Will look locally for a decent tester for $200 or so for the other homemade / restored amps (Dynakit ST-70, 2A3 PP, Heathkit W5M, WPA-2, AA-32, Eico tuner).
    FWIW, having a grand time constructing the SOB. With schematic in hand and the nice touch of color coded wire for the different signals, this is bringing me back to the 1970's DeVry Tech days! Quite the maze on the puppy tube sockets though! Will have to get creative on the coupling caps -- purchased some larger Mundorf SGO's for kicks.

    sKiZo

    Posts : 1308
    Join date : 2013-04-01
    Location : Michigan USA

    Re: Tube Tester

    Post by sKiZo on Fri May 16, 2014 2:12 pm

    sailor wrote:Hi skizo, were these comments for me?

    Just general commentary on tube testers in general, long as we're on the subject ...

    Another item - most older testers that don't have the newer style sockets can be adapted quite readily using an outboard box that usually plugs into the octal socket. The grid cap is used to provide the missing signal for 9 pin tubes. I got lucky in that the official factory adapter came with mine, modded and ready to go.

    Some testers will require a bit of internal modification, so best to search your particular model if you need to expand. You can usually find test data for newer tubes also if you dig hard enough. I found a nice Excel sheet that covers a LOT of tubes not included in the latest Precision tester rolls.

    MontanaWay

    Posts : 781
    Join date : 2014-02-06
    Age : 58
    Location : Brookings, Oregon

    Re: Tube Tester

    Post by MontanaWay on Fri May 16, 2014 3:22 pm

    sKiZo wrote:
    sailor wrote:Hi skizo, were these comments for me?

    Just general commentary on tube testers in general, long as we're on the subject ...

    Another item - most older testers that don't have the newer style sockets can be adapted quite readily using an outboard box that usually plugs into the octal socket. The grid cap is used to provide the missing signal for 9 pin tubes. I got lucky in that the official factory adapter came with mine, modded and ready to go.

    Some testers will require a bit of internal modification, so best to search your particular model if you need to expand. You can usually find test data for newer tubes also if you dig hard enough. I found a nice Excel sheet that covers a LOT of tubes not included in the latest Precision tester rolls.

    any chance of sharing that Excel data??  Smile 

    Pillo69

    Posts : 105
    Join date : 2012-04-11
    Location : Granada (España)

    Re: Tube Tester

    Post by Pillo69 on Fri May 16, 2014 7:24 pm

    Hello.
    They have offered me this device, I do not know not to be European manufacturing operation.
    You believe it may be a good choice?.

    http://subefotos.com/ver/?0eaa8f23e2f670aaf530a162bbba2cf4o.jpg

    sKiZo

    Posts : 1308
    Join date : 2013-04-01
    Location : Michigan USA

    Re: Tube Tester

    Post by sKiZo on Sat May 17, 2014 1:34 am

    MontanaWay wrote:

    any chance of sharing that Excel data??  Smile 

    Won't do you any good as it's specific to the Precision testers ... but you asked for it.

    http://pcbunn.cacr.caltech.edu/jjb/Precision/P660_settings.xls




    sKiZo

    Posts : 1308
    Join date : 2013-04-01
    Location : Michigan USA

    Re: Tube Tester

    Post by sKiZo on Sat May 17, 2014 1:40 am

    Pillo69 wrote:Hello.
    They have offered me this device, I do not know not to be European manufacturing operation.
    You believe it may be a good choice?.

    http://subefotos.com/ver/?0eaa8f23e2f670aaf530a162bbba2cf4o.jpg

    Looks like it's got a 9 pin socket ... lower left of the left bank ... so that would mean it should be able to handle anything you need to test ...

    Never heard of it myself ...

    MontanaWay

    Posts : 781
    Join date : 2014-02-06
    Age : 58
    Location : Brookings, Oregon

    Re: Tube Tester

    Post by MontanaWay on Sat May 17, 2014 4:54 pm

    Pillo69 wrote:Hello.
    They have offered me this device, I do not know not to be European manufacturing operation.
    You believe it may be a good choice?.

    http://subefotos.com/ver/?0eaa8f23e2f670aaf530a162bbba2cf4o.jpg

    not heard of this make before.
    Personally I would try and stick to the more commonly available Hickok testers, as there are quite a few out there for sale, not to mention a ton of info & literature as well as spare parts, just my 2cents worth  Very Happy 

    sKiZo

    Posts : 1308
    Join date : 2013-04-01
    Location : Michigan USA

    Re: Tube Tester

    Post by sKiZo on Sat May 17, 2014 6:39 pm

    It does look suspiciously like a Precision ... even has the same model number ...

    Forgot I had this one ... the Dynaco of the tube tester world. Lucky me, this one looks to be factory built, or at least put together by someone who knew what they were doing. Pretty well regarded amongst us amateurs.



    Nice little tester that does do octal and 9 pin ...

    PS ... about the excel data ... NORMALLY, there's only one basic difference in that some testers number their controls, and some use letters. Usually a safe bet to just figure that A=1, B=2, C=3. D= ... er ... 42?

    sailor

    Posts : 269
    Join date : 2011-04-04

    Re: Tube Tester

    Post by sailor on Sat May 17, 2014 10:32 pm

    My dad started fixing TV around 1957. I have to pull out some of his old pictures and see what he bought new back then. I know it had the meter in the center like this one but I don't think it was a Knight.

    tubes4hifi
    Admin

    Posts : 1282
    Join date : 2008-11-30

    Re: Tube Tester

    Post by tubes4hifi on Sun May 18, 2014 1:53 pm

    I had a Heathkit TT-1 a few years ago, much nicer than any of the Hickocks I've had, the TT-1 was one of the nicest tube testers ever made


    anbitet66

    Posts : 132
    Join date : 2009-12-23
    Location : Valley Stream, NY

    Re: Tube Tester

    Post by anbitet66 on Sun May 18, 2014 6:31 pm

    sKiZo wrote:It does look suspiciously like a Precision ... even has the same model number ...

    Forgot I had this one ... the Dynaco of the tube tester world. Lucky me, this one looks to be factory built, or at least put together by someone who knew what they were doing. Pretty well regarded amongst us amateurs.



    Nice little tester that does do octal and 9 pin ...

    PS ... about the excel data ... NORMALLY, there's only one basic difference in that some testers number their controls, and some use letters. Usually a safe bet to just figure that A=1, B=2, C=3. D= ... er ... 42?

    sKiZo,

    It looks like a Precision because it is!  The Precision name is on the lower right of his unit.

    I get a kind of special kick out of all sorts of devices from "back in the day" since they used to put where it was manufactured right next to the name.  Precision was one of many companies located in New York.  The tube tester you pictured (series 920) even went to the geographically correct statement of "Elmhurst LI NY, USA".  Today, anyone living on Long Island will protest that since Elmhurs is in Queens NY, one of the 5 Boros of NYC.  But it's still on the west end of Long Island, about 10 miles from where I now live.  Many other companies were here such as EICO and Granco just to name two ('cause i'm blanking out on more).  Too bad most shut down or moved away. Crying or Very sad

    MontanaWay

    Posts : 781
    Join date : 2014-02-06
    Age : 58
    Location : Brookings, Oregon

    Re: Tube Tester

    Post by MontanaWay on Sun May 18, 2014 7:51 pm

    tubes4hifi wrote:I had a Heathkit TT-1 a few years ago, much nicer than any of the Hickocks I've had, the TT-1 was one of the nicest tube testers ever made


    that is a nice looking unit, I assume it worked just as well too

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