Hickok 246 Bar Generator - Videokarma.org TV - Video

TinCanAlley · #1 02-16-2026, 01:35 PM

I just got this unit and it tested out well. The manual goes over quite a few test procedures and the one I want to use is the ability to cut off the color guns. The unit has three leads with alligator clips that also have piercers for the wires. My only issue... I don't know which leads to clip them to. The CRT socket has three sets of wires for the different colors (yellow with color lines of red, green and blue, white wires with color lines and separate red, green and blue wires). I'm not sure which wires to connect to. Also, I would imagine once I know which wires, there are probably points I could connect to that doesn't require piercing the wires.

old_tv_nut · #2 02-16-2026, 07:37 PM

Look up the CRT spec sheet, or look at the set schematic.
The pins you want to ground to cut off a gun are the G1 (grid 1) connections.

TinCanAlley · #3 02-17-2026, 05:48 PM

Quote:

Originally Posted by old_tv_nut

Look up the CRT spec sheet, or look at the set schematic.
The pins you want to ground to cut off a gun are the G1 (grid 1) connections.

I've looked, but the SM doesn't note which is which. I determined the G2s are white with 540 to 640V, so those I don't want. The other two sets are the video outputs and are yellow and have 142V and the last set are R, G and B and have voltages of 36.4V. I'm assuming the video outputs of 142V are G1? Those are also where the chroma gain taps are.

So if the yellow leads from the video outputs are the G1s, then they have test points that I should be able to connect the gun killer clips to. Those test points are where the G1 wires go to the CRT.

Electronic M · #4 02-18-2026, 07:56 AM

G1 should be negative WRT cathode so logically the yellow stripped ones are the cathodes and RGB solid are the grids... pretty sure that was standard color code going back to the late 50s too.

TinCanAlley · #5 02-18-2026, 04:52 PM

Quote:

Originally Posted by Electronic M

G1 should be negative WRT cathode so logically the yellow stripped ones are the cathodes and RGB solid are the grids... pretty sure that was standard color code going back to the late 50s too.

I feel so stupid not being able to fully understand this, so I just spent a bit of time reading all I could find. So now I think I have it. The Cathode is first in line and is feed the 14xV from the video outputs. The next is grid 1 that is feed from the 240V boost and is the 34.6V (these should be negative voltage). The next is grid 2 fed by the 750V boost. Lastly is the Focus fed by the tripler.

So if I do have this correct, then I need to use the gun killer leads on the solid color leads, R, G and B.

What are the consequences if I hook the gun killer leads to the wrong grid?

Electronic M · #6 02-19-2026, 12:18 AM

Diagram is properly labeled.

If you mean mixing up the 3 grid leads it will just mean the gun killer color labeling will be similarly mixed up in use that way.

If you mean getting G1, G2, Cathodes leads mixed up.... G2 if you short it to ground will blank its color (G2 driver circuits could be damaged if the switch doesn't have a high enough built in resistance. If you short cathode to ground then the gun will be turned on more than the TV normally can it'll lharm the gun if operated that way for more than a few seconds, may harm the cathode drive circuits if let run like that long.

Most Delta gun sets would inject monochrome luminance monochrome video to the 3 cathodes, and R-Y to the red grid, G-Y to the green grid, and the same pattern for blue... The RGB video only existed in the electron stream as a result of grid and cathode signals adding. Around that time some Zeniths did it backwards Luminance on the grids and R-Y, G-Y, and B-Y on the cathodes.... Some other makes did it like that too depending on who the engineer was.

TinCanAlley · #7 02-21-2026, 03:46 PM

Okay, 2 more questions about using this new to me unit....

The Leader unit I have has a BNC for connection to a scope for triggering. This unit also has the triggering ability, but it doesn't have a BNC connector. It uses VOM 2mm pin leads with minigrabbers. I'm assuming I should connect a probe in 1x mode and connect the leads to it? Or is there a BNC connector that is designed to connect the leads to?

It also has a video out feature that inserts the signal directly to the video circuit. It says to insert directly after the detector. How do I find this point? I'd like to bypass the tuner and IF to see if there's any difference in the color issues. Not sure this is the right way, but I figure that removing any possible source for testing can't hurt.

TinCanAlley · #8 02-21-2026, 03:49 PM

Quote:

Originally Posted by Electronic M

Diagram is properly labeled.

If you mean mixing up the 3 grid leads it will just mean the gun killer color labeling will be similarly mixed up in use that way.

If you mean getting G1, G2, Cathodes leads mixed up.... G2 if you short it to ground will blank its color (G2 driver circuits could be damaged if the switch doesn't have a high enough built in resistance. If you short cathode to ground then the gun will be turned on more than the TV normally can it'll lharm the gun if operated that way for more than a few seconds, may harm the cathode drive circuits if let run like that long.

Most Delta gun sets would inject monochrome luminance monochrome video to the 3 cathodes, and R-Y to the red grid, G-Y to the green grid, and the same pattern for blue... The RGB video only existed in the electron stream as a result of grid and cathode signals adding. Around that time some Zeniths did it backwards Luminance on the grids and R-Y, G-Y, and B-Y on the cathodes.... Some other makes did it like that too depending on who the engineer was.

Okay, now I'm sure the RGB leads on the CRT are the ones I want for the killer leads. The manual says they are connected to 100,000 ohm fixed resistors. Of all the pics I took of the chassis (above and below) you'd think I'd have at least one clear picture of where those leads go once they pass through the hole in the rear of the chassis, but all my pics show them disappear under a bunch of other wires. Something tells me there are not connection points and I'll have to use the wire piercers.

TinCanAlley · #9 03-30-2026, 04:20 PM

I just noticed something I overlooked all this time. There is a test point on the chassis labeled "C1". It wasn't referenced in the SM, so I figured it wasn't actually used on this set. Today I was looking over the glued on paper inside the set that has a layout of the chassis and note all modules, transistors, etc. In the top corner is a list of the test points not labeled with a tag. It notes C1 as being the test point for "video detector output". Doing some internet searching I've found that this test point allows you to test the signal before it hits the video stages so you can see if noise is there before it hits them. I also found that this TP can be used to inject the signal directly from my generator, but I don't know if it's that simple. If I connect my generator's output to this point, how does it override the IF's signal? If I can do this, I should be able to bring up a raster with the generator and see if my jail bars are from the IF section. Never been able to test that before.