Re: Safely Discharging a Flyback Transformer.
You can make a tool to discharge the CRT using a wire with a croc clip one end, a highish value resistor (if you want to avoid the HV crack as it discharges) and an insulated screwdriver. Attach the end of the wire with the resistor to a metal part of the screwdriver, clip the croc clip end on the CRT GND (the aquadag connection, usually a braided wire around the bowl of the CRT). Slide the tip of the screwdriver under the anode cap to touch the connector (may be a spark), and leave it a while. The lower the resistor used, the faster the discharge (and the bigger the spark!).
Be aware that CRT's recover some charge slowly, so I find it best to connect a lead with a clip each end into the eht connector cavity with the other end on the dag.
The shock from a CRT isn't usually lethal but can be unnerving and if you're carrying a tube you could drop it or have some other disaster on being caught unaware.
They changed the recommended procedure for discharging CRT's years' ago due to the shift to transistor sets. With valve equipment it was normal to just shove a screwdriver between the metal chassis and the anode as there were no delicate semiconductors that could be potentially damaged.
All I used to do was remove the dag ground connection from the CRT base, squeeze the anode cap to allow it to be unhooked from the cavity, then holding the dag wire with a pair of insulated pliers approach the cavity until a spark jumped between the two, finally leaving the dag wire inside the cavity.
You can make a tool to discharge the CRT using a wire with a croc clip one end, a highish value resistor (if you want to avoid the HV crack as it discharges) and an insulated screwdriver. Attach the end of the wire with the resistor to a metal part of the screwdriver, clip the croc clip end on the CRT GND (the aquadag connection, usually a braided wire around the bowl of the CRT). Slide the tip of the screwdriver under the anode cap to touch the connector (may be a spark), and leave it a while. The lower the resistor used, the faster the discharge (and the bigger the spark!).
Be aware that CRT's recover some charge slowly, so I find it best to connect a lead with a clip each end into the eht connector cavity with the other end on the dag.
The shock from a CRT isn't usually lethal but can be unnerving and if you're carrying a tube you could drop it or have some other disaster on being caught unaware.
They changed the recommended procedure for discharging CRT's years' ago due to the shift to transistor sets. With valve equipment it was normal to just shove a screwdriver between the metal chassis and the anode as there were no delicate semiconductors that could be potentially damaged.
All I used to do was remove the dag ground connection from the CRT base, squeeze the anode cap to allow it to be unhooked from the cavity, then holding the dag wire with a pair of insulated pliers approach the cavity until a spark jumped between the two, finally leaving the dag wire inside the cavity.
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