CRT Tester - Page 1
Forum section: electronics / testgear

author: Simon123
author_rank: Regular Contributor
timestamp: January 12, 2014, 06:09:29 pm
content: Hello!I have bought thishttp://www.radiomuseum.org/r/eurotron_bildroehrenregenerierger.htmlcrt tester/rejuvenator on flea market for 7€.What do all functions on the bottom dial mean?, the top one is for filament voltages?How to use this device?Does anywhone have it, beacuse inside there are 2 wires, on which apears, some component was cutt off, and on the connector for crt there is solder on one pin, but there isnt anything connected to.

author: Rerouter
author_rank: Super Contributor
timestamp: January 12, 2014, 07:31:06 pm
content: you would need to post better images, i myself have never even seen such a device, but during my search for a replacement CRT i did come across this datasheet which may be able to helphttp://www.mouser.com/ds/2/43/CRT_datasheet-180889.pdf(down the bottom mainly, it tells you pin-outs and heater voltage for each tube)

author: Simon123
author_rank: Regular Contributor
timestamp: January 12, 2014, 08:24:20 pm
content: Here are some pictures.I will change caps, thats why i have it apart.

author: SeanB
author_rank: Super Contributor
timestamp: January 12, 2014, 08:32:57 pm
content: Well it is in Dutch so translatable.Top knob is heater voltage. either off, 2V, 6V3 or 8V. Probably AC from a set of windings on the main transformer. Used to check tubes and rejuvenate low emission heaters.Lower knob.Leak test, emission test, shorted electrode test then a low and high EHT test. Basically tests the tube that it will act as a basic rectifier and the grids can control the emission of the tube.The 3 neon's show heater leakage, G1 current and G2 current by lighting on current flow due to shorted electrode assemblies. Basically you connect the tube using the common base pinouts for CRT's and then connect the EHT to the anode connection on the side of the tube then power the device and select the test then press the button. Read the values off the meter and compare to manual for readings.

author: Simon123
author_rank: Regular Contributor
timestamp: January 12, 2014, 09:00:49 pm
content: ThanksIn manual it says, that if measurment is less than marked with red dot, you should do the shorted electorde test.-is this correct?And are you shure about pressing the button, when you wana test the tube, beacuse it says Reg., which means regenerate-rejuvenate the tube?

author: PaulAm
author_rank: Frequent Contributor
timestamp: January 12, 2014, 11:35:03 pm
content: You want to be careful with CRT rejuvenation, done improperly it can strip the cathode and render the crt useless.If you want to get a feel for how these things work, look for a document online for a Sencore CR70. They have a nice explanation of what happens during a rejuvenation process, what causes CRT failure, etc.Unless I had a throwaway CRT, I'd be wary of using any CRT tester that I did not fully understand.

author: Simon123
author_rank: Regular Contributor
timestamp: January 13, 2014, 09:18:35 pm
content: Thanks!Now i have rewired the Vf switch, beacuse i was getting voltages in wrong order.I now get 1.8V on 2 V range-based on calcs should be 1.5V, 8V on 6.5 Winding and 10V on 8V winding.Will the voltages drop, beacuse there isnt any load right now?

author: Rerouter
author_rank: Super Contributor
timestamp: January 14, 2014, 09:37:34 am
content: attach a low value resistance like 180 ohms across the terminals (i'm reading that 40mA is around the upper on heater current for test gear restoration)