I went to my friend’s house to test my “old” Knight 600 Tube Tester. It was old, I got from eBay. I didn’t have step down transformer on hand, so I need to try it elsewhere.
It was a nice unit. Some rust on the screws, but overall all the functions were functional. The roll chart was working completely, no sign of jammed or stucked. This “simple emission tester” could check most tubes, from classic 4 pins to Octal and Nuvistor tube.
Disassembly of the unit. I needed to remove some screws from the top of the unit. It was a simple job.
Back panels of the Tube Tester. Actually, it was a simple machine, because this was only an emission tester. Basically, it contained transformer, some necessary sockets, C-load mechanism, a meter, and some levers/buttons to properly connect the circuit depended on the tube tested.
The main transformer. It has a 25W “line adjust” potentiometer to compensate the “correct” level of the voltage. Well, it was an ancient technology. No switching system or input stabilizer, remember! 🙂
The main transformer has a lot of taps (21 secondary taps, if I could recall my brain correctly) for the filaments and main High Voltage. Again it was old, but still fully functional.
The circuit selector button, from A to D, a C-Load selector, and some other button. We need to adjust it, depended on the tube tested. I could see one “strange” black/red resistor with “Holland” written on the body. What was that? 🙂
The roll chart and two neon bulb. Well, I need to have this data on my computer, since searching tube with this roll chart was pulling up my nerves.
My friend, Fajar, with my Knight 600 Tube Tester. I used his step down transformer to test this Tube Tester.
Greg Vitercikq
March 4, 2009 10:53I think the black / red “resistor” is a 1N4007 diode that has replaced the original rectifier at some point. (The rectifier would normally be a little to the left of where the new diode is, and it isn’t there.)
Apparently the rectifier could go bad, making it impossible to calibrate the tester. Have you seen the article at http://tubesound.com/2008/05/31/knight-600-tube-tester/ ?
I think I may have fried my rectifier, so it’s very helpful to see your photos.
Jimmy Auw
March 4, 2009 21:05Hi,
Yes I have visited that page before.
Thank you.
Erwin H
June 23, 2009 22:30Bos Jimmy, kira2 menerima jasa test tube gak?
pengen check tube GEC TT22. Kira2 ada problem / gak di tubenya….
Jimmy Auw
June 23, 2009 23:47Coba swap kanan-kiri lampunya bro, masih sember gak?
Tube Tester saya model lama, kurang akurat, dan belum sempet dikalibrasi. Kalo buat iseng2 aja sih ga masalah, tapi kalo buat liat “kesehatan” seperti kasus bro, tester ini boleh dikatakan tidak mampu. Mesti pake yang kelasnya “mutual conductance” instead of “emission tester” seperti punya saya ini.
Thanks.