21fb j p22

[old_tv_nut]

Originally Posted by Yamamaya42

Or they just had a HUGE stock of 22m 6k resistors on hand!

Or, at the time, they could buy three 22M for less than one 66M.

[timmy]

Originally Posted by Yamamaya42

did you ever do the heater voltage tests?

I didn’t do the heater voltage test yet

[reeferman]

Originally Posted by DavGoodlin

Great story! E J Korvette sold many Motorola sets in mid Atlantic, even the 19" BW my parents got in 63, but did they have a service department?

Not in St Louis.

[kvflyer]

Originally Posted by reeferman

Not in St Louis.

I worked in the EJ Korvette in Catonsville (Baltimore), MD right out of right school. I worked in the Audio Department. The only repair facility was in our Audio Department and it was only for the equipment that we sold in that department. Televisions were in the department next to us. And remember how color sets were always in a darkened room?

[julianburke]

Years ago in working with Zenith TV's I came across a Zenith roundie with a CRT that had a Zenith brand sticker/label on the top of a RCA label. They were either too lazy or didn't care.

[julianburke]

[QUOTE=Electronic M;3253618]Zenith/rauland made their own, RCA did, and so did Sylvania. Easiest way to know who REALLY made a tube is to look up the EIA number on the label. I've seen Zenith labeled roundy tubes that had Zenith, Rauland (Zenith subsidiary) and RCA EIA codes. The RCA tube appeared to be early into Zenith selling roundys.


Many years ago the CRT's were in somewhat short supply. If you made your own tubes you were in the drivers' seat for making as many sets as you wanted. Smaller manufacturers had to depend on what ever they could get ie; Curtis Mathis and others like them. Yes, they also traded around as in contract marketing. Smaller vacuum tubes were also treated and traded the same way.

[timmy]

Anyone know how these work I have used one in the past but don’t know how this works by boosting the gun but does not change heater voltage. They do work good without changing the heater voltage.

[old_tv_nut]

Originally Posted by timmy

Anyone know how these work I have used one in the past but don’t know how this works by boosting the gun but does not change heater voltage. They do work good without changing the heater voltage.

Are you sure? I can't imagine how that's possible.

[timmy]

Originally Posted by old_tv_nut

Are you sure? I can't imagine how that's possible.

I did post the same question years ago but don’t remember the result. I think it was taking voltage from somewhere else within the plug there is an adjusting pot and no transformer inside since I took one apart befor and all there is inside is a resistor and a pot.

[Yamamaya42]

I'm not sure which one you got and opened, but the way that most work is on 2 levels, first is by boosting heater voltage from 6.3 to at least a volt or more higher via a transformer in most cases, second is by isolation which may sometimes help in H-K shorts.

[timmy]

Originally Posted by Yamamaya42

I'm not sure which one you got and opened, but the way that most work is on 2 levels, first is by boosting heater voltage from 6.3 to at least a volt or more higher via a transformer in most cases, second is by isolation which may sometimes help in H-K shorts.

These brighteners came red green and blue depending on what gun is weak the pic is for the red gun they are colored. I had taken a green one apart and the heater connection is not touched at all just wires from the gun that will be boosted to a resistor and a pot that’s it

[Yamamaya42]

I'm unfamiliar with how those type might work, never having seen one, they must be trying to alter the bias of the “weak” gun in relation to the others to try and balance things out, but I can't imagine that working out so well vs a real booster that kicks up the heater voltage, which is only a Band-Aid to start with.

[timmy]

I used one on another set with a really weak red gun could not get a white screen not enough red but after plugging one of these in it never changed the green and blue adjustment only the red just turned the pot up alittle and viola had more the enough of red. It is odd not to increase the heater voltage but it don’t but they do work well.

[old_tv_nut]

Originally Posted by timmy

These brighteners came red green and blue depending on what gun is weak the pic is for the red gun they are colored. I had taken a green one apart and the heater connection is not touched at all just wires from the gun that will be boosted to a resistor and a pot that’s it

It has a pot that is accessible for adjustment (not visible in the photo)? Must be changing the G2 range on the affected gun.

[Yamamaya42]

The only thing I think it may have been doing is altering the cathode bias beyond the standard ranges on the tube for the weak gun, and thus pushing the drive level even harder, but that can't be very good for a weak gun on a tube, likely to burn it up fast.