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Equipment Repairs => CRT TV forum => Topic started by: rodneysccx on October 28, 2008,06:59:09
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hello to all out there
anyone know how to spark CTV RGB gun
any type of CTV tube
i hope someone know it
bye and thk
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it depends on tv chassis used, if set uses osolated chassis proceed with caution, i assume you dont have crt tester\booster. some tubes respond better than others.
identify the control grid, may be common or seperate pins, disconnect any circuitry around it and apply and between the ht (not eht) connect a 60w bc lamp. then ground the appropriate cathode to deck, briefly, if the cathode is not totally stripped youo should be well, as i said different crt,s react differently, u could kill the crt totally
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should read isolated
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Heres a fun way to remove shorts in a CRT tube.
PLEASE NOTE: THIS PROCEDURE IS DONE AT YOUR OWN RISK. IT'S YOUR LIFE, SO TAKE GREAT CARE WITH THE ULTOR HIGH VOLTAGE!
To remove shorts in CRT, first ascertain if the short is related to the focus, G2, grids or cathodes.
1. Run earth braid in, out, around good pins on CRT, leaving the offending pin exposed.
2. Earth good pins to aquadag of CRT.
3. If the focus is the offending item, disconnect the ULTOR from CRT, make sure the ULTOR lead is clean from grease etc. Clean with ultrasolve or something similar & wipe dry.
4. Turn on TV & spark the focus pin with the ULTOR, you may have to do this twice. Disconnect earth strap reconnect ultor & test.
5. If the G2, Grid or Cathode is the offending element, disconnect the FOCUS from the CRT socket, perform the same set up as in steps 1 & 2. again you may have to do this twice also.
6. NOTE: IT IS IMPORTANT THAT THE HEATER PINS ARE SECURELY EARTHED, AS YOU DO NOT WANT TO COOK THEM.
Have fun
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bit vicous but excellent method
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I was very skeptical about this method when I heard it, but I have to say it works 90% of the time.
Not for the faint hearted though :bo:
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Have a diagram of a device somewhere from the late 70's it used parts from an old Philips G8
Crt 6volt Transformer G8
1n4007 diode
240volt 60-100watt lamp, wattage depending how fierce you need to be.
CRT base for tube type, if not flying leads have to be used, (not advised for safety.)
The G8 RGB gun switches were also used to tickle each cathode as needed.
If I can't find the diagram I will attempt to draw from memory as soon as possible.
This device kept crts going at least an extra 2 years before crt replacement was considered. A great saving with a 1k TV rental business 70's and 80's.
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Rodneysccx, what BC109 has explained is a wonderful method! Recently I tried it for removing green cathode with filament. Thanks BC109. What he means is 1) first find out which pin is shorted with whom. 2) isolate this pin from circuit track 3) connect all other crt pins to chassis ground by isolating them also from rest circuit 4) if shorted pin is focus then connect final anode to it 5) if shorted pin is other i.e. cathode, grid (control or screen) then connect focus wire from FBT to it. Start set momentarily to produce spark. The spark then removes short. While doing this risk is always there!!
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Remove CRT PCB from tube.
I use solder wick and weave it around all pins to be earthed, connect to clip lead then to earth (aquadag).
Use another clip lead to connect to faulty pin, then strike HT to end of lead twice.
I see a lot of newish LG's with shorts, and this clears about 90%. Nothing to loose.
BUT PLEASE NOTE THIS IS DANGEROUS IF YOU DONT KNOW ABOUT TV HIGH VOLTAGE!!!!
Is your life worth a TV?
If the above needs any more explaining DONT DO IT!