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-   -   21fb j p22 (http://www.videokarma.org/showthread.php?t=276180)

Yamamaya42 11-07-2023 10:27 AM

I suspect it's on pins 4 ,13 or 5, depending on what ever color it was made for.

damen 11-07-2023 10:30 AM

Those types of "boosters" were advertised in a lot of the electronic magazines back in the day. The most basic ones came with splice connectors to use on which ever gun needed it. It's just a pot and limiting resistor connected between the screen and grid of the gun.

timmy 11-07-2023 10:39 AM

Quote:

Originally Posted by Yamamaya42 (Post 3254237)
which ones on the socket??

This brightened is for the green gun so there is solid green and green and white the solid green goes to center of pot and the green and white goes to a resistor and soldered to one end of the pot and both go out to the tube.

old_tv_nut 11-07-2023 10:54 AM

I found the basic patent with a schematic:
https://patents.google.com/patent/US4139861

The idea is to reduce the negative g1-cathode bias, increasing the current in the gun (but also ruining the lowlight tracking, which is then restored by adjusting the cutoff with the set's G2 controls).

Yamamaya42 11-07-2023 10:58 AM

edit, Ahhh so my first thought was right!
Lower the cathode voltage a bit! :P

timmy 11-07-2023 11:05 AM

Ok so now we all have a better understanding of this anomaly device.

Yamamaya42 11-07-2023 11:11 AM

Of course, regardless of how it's done, it's like putting a band-aid on a gunshot wound, only will delay the inevitable, for a wile. :(

timmy 11-07-2023 11:28 AM

While it is a weird device it does work and it probably would work longer then a brightener that increases the heater voltage for that gun it’s being used for. Increasing the heater voltage creates more heat and would burn off more cathode material faster then if it were at the proper voltage. Just my thought on this.

jr_tech 11-07-2023 02:16 PM

Early thread discussion of the booster:


http://www.videokarma.org/showthread...hlight=booster

jr


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