![]() ![]() Of course, we are discussing vacuum tubes here - devices that are about as variable as ears of corn, and not hardly precision devices. Given the thousands of tube variants with many levels of "Quality" within each family, and to satisfy many irrational expectations, your software would have to be very robust. Software is available for existing hardware, you may even be able to derive that as well without having to program from scratch. If you could come up with a practical DIY solid-state tube tester with the ability to show performance curves and at a reasonable cost, likely you will do quite well. Some are incredibly sophisticated, far beyond the actual need, but for those who believe in them, quite nice. Some use existing technology - outboard additions to a Hickok Cardmatic, for example, and some that are stand-alone products. There are several digital tube testers out there, and even a few that connect to a PC or laptop. On Monday, Septemat 8:07:04 PM UTC-4, Big Bad Bob wrote: Testing afterwards to verify the operating characteristics, with Hand-blown glass and everything - it was on a video. [some time ago I saw a web page where someone made his own tubes, It might also be useful to find (or verify) 'matched pairs'. Mentioned above is asking for HIS tube testers ($500 or so each I guess) Less to build (in parts, not time) than what the guy on that web site I Similar) since the max current on those is ~400ma (0V g1, 300V g2, 66VĪnyway this is just a mental exercise at the moment. Even somethingīiggest problems would be testing larger tubes like KT88 (or something There, done that], again with the proper external parts. Something like that is relatively easy for a microcontroller [been Let the tube warm up, then apply test voltages in a reasonable order,Īnd measure the resulting cathode current. You'd first do a pin-pin conductivity check, then energize the heater It might be a fun project (even if I'm the only one in the world who'd With a microcontroller, given the proper external parts. Generating voltages and measuring currents would be trivial things to do Maybe saved in a database or something (pins with voltage levels andĬurrents), and some 'more modern' device could THEN run the test, under In it, a test COULD be devised for the types you typically want to test, if you've got a good tube book handy with the standard curves I'm guessing yours is one of those "good ones". Tube under some conditions, drawing ANY kind of current on G1 being one ![]() ![]() I would guess THAT kind of test might even be bad for the REAL test, not just an emissions test with grids+plate tied together There are some really GOOD testers out there that put the device under a OK from what I'm reading, on sites like THIS one: Rid of most of my really old test gear for various reasons, "no room" I bought it at a swap meet for something cheap. Switches on it, and a big paper roll with all of the switch positions. Long ago I had an 'emissions' style tester with the usual 3-position You MUST let me know before the end of today (Monday) as I will need to cobble up the dummy load required for the test. On the other hand, if you are anywhere near Kutztown this Friday/Saturday for the big show, bring your tester to the club table, and I would be glad to run through the calibration for you. I keep a Hickok 539B, and after going through the calibration process, once, I have a 6L6 and an 80 that I tested over twenty (20) years ago. THESE will become your indicator/test tubes. The reading(s) should be very nearly identical. Every so often, after a few hundred hours of use, re-test the tubes. Mark the reading(s) on the tube with a Sharpie. ![]() In any case, I suggest the following moving forward, and whether you do the calibration yourself or send it out: Once done, pick a couple of basic triode tubes, perhaps an 80 and a 45 (one rectifier and one power tube), or a basic pentode powere tube such as, perhaps, an EL84. If you are adept with tubes - implied by owning and using such a tester - and if you have a reasonably accurate VOM (most are, these days), you can do it yourself fairly easily. However, I did look through the manual for that unit ( ) and there is one (1) adjustment for calibration. What makes you think that you need a calibration? There are two very long-lived tubes in that beast (12AU7 & 6C4) that, unless they are seriously worn out, you should experience no drift in calibration for their (reasonable) life. Can you folks direct me to who us radio enthusiasts are now trusting with our testers? Any and all help is greatly appreciated! > Well, I had my Triplett 3444 calibrated by Chris Haedt before he passed, God rest his soul. On Sunday, Septemat 4:05:55 PM UTC-4, Balekan wrote: ![]()
0 Comments
Leave a Reply. |
AuthorWrite something about yourself. No need to be fancy, just an overview. ArchivesCategories |