Home |
Search |
Today's Posts |
#1
Posted to rec.audio.tubes
|
|||
|
|||
batch-testing 6sn7 with Hickok 533a
I constructed an adapter to batch-test 6sn7 or 6sl7 with a Hickok 533A
I compared the results of a tube in the batch with these of a single tube in the tube tester. The values are somewhat lower e.g. 2950 micromohs becomes 2900micromohs. I wonder how that comes. Can it have something to do with the heater circuit? The adapter holds 12 sockets with all filaments connected in parallel to a powerfull filament transformer. All cathodes and grids are connected together and to the proper tube tester socket pins. The test lead is connected to the anode circuit at the tube tester. After letting the tubes heat up, the transconductance of each triode can be measured fast by contacting the anode one by one. The links below point to a few pictures of the setup: http://users.skynet.be/m28/TubeGalle...s/08160005.JPG http://users.skynet.be/m28/TubeGalle...s/08160006.JPG Thanks for any advise. Patrick |
#2
Posted to rec.audio.tubes
|
|||
|
|||
batch-testing 6sn7 with Hickok 533a
Patrick wrote: I constructed an adapter to batch-test 6sn7 or 6sl7 with a Hickok 533A I compared the results of a tube in the batch with these of a single tube in the tube tester. Looks like with the proper lash-up, you could bulk test about any octal-socket tube that way. I do not see that the 533A has matching capacity, but that system would even work with a tester so-equipped. Peter Wieck Wyncote, PA |
#3
Posted to rec.audio.tubes
|
|||
|
|||
batch-testing 6sn7 with Hickok 533a
schreef in bericht oups.com... Patrick wrote: I constructed an adapter to batch-test 6sn7 or 6sl7 with a Hickok 533A I compared the results of a tube in the batch with these of a single tube in the tube tester. Looks like with the proper lash-up, you could bulk test about any octal-socket tube that way. I do not see that the 533A has matching capacity, but that system would even work with a tester so-equipped. Peter Wieck Wyncote, PA I have tested 12 double triodes in the time needed for one with this fixture. It works great. For penthodes and beam power tubes I think a second testprobe to grid2 would be necessary. And for multigrid tubes as well... |
#4
Posted to rec.audio.tubes
|
|||
|
|||
batch-testing 6sn7 with Hickok 533a
Patrick wrote:
I constructed an adapter to batch-test 6sn7 or 6sl7 with a Hickok 533A I compared the results of a tube in the batch with these of a single tube in the tube tester. The values are somewhat lower e.g. 2950 micromohs becomes 2900micromohs. I wonder how that comes. Can it have something to do with the heater circuit? I've seen grid stoppers used in some setups like this. To avoid any chance of a tube going into oscillation. |
#5
Posted to rec.audio.tubes
|
|||
|
|||
batch-testing 6sn7 with Hickok 533a
"robert casey" schreef in bericht ink.net... Patrick wrote: I constructed an adapter to batch-test 6sn7 or 6sl7 with a Hickok 533A I compared the results of a tube in the batch with these of a single tube in the tube tester. The values are somewhat lower e.g. 2950 micromohs becomes 2900micromohs. I wonder how that comes. Can it have something to do with the heater circuit? I've seen grid stoppers used in some setups like this. To avoid any chance of a tube going into oscillation. I just checked a batch of 12 6SN7GT tubes with this setup (adapter + Hickock 533A), while monitoring the anode voltage with a Tektronix 2445B 150MHz oscilloscope. None of the triodes showed signs of oscillation. |
Reply |
Thread Tools | |
Display Modes | |
|
|
Similar Threads | ||||
Thread | Forum | |||
Testing Russian 6E5C on Hickok 800k | Vacuum Tubes | |||
FA: HICKOK 533A TUBE TESTER !!!! | Vacuum Tubes | |||
FA: HICKOK 533A TUBE TESTER !!!! | Vacuum Tubes | |||
Comments about Blind Testing | High End Audio | |||
Testing 3C23 tubes In Hickok 600A Tester | Vacuum Tubes |