Sylvania Superset Update

[TrllVl90]

Originally Posted by JohnCT

I don't think the tube would even light at 2.2V. The meter is on "AC" (~), correct?

Have you verified the meter? Try it on your wall plug to see if you are getting about 120VAC.

If the retrace cap is low in value, the HV and filament would be high.

I don't recall the pin numbers of the filaments, but they should read very low ohms (power off) across the filament pins (couple of ohms) if you are on the right pins.

Since sweep is regulated, the voltage will be the same hot or cold.

John

Hey John,


Yeah the meter gets calibrated everyb6 months for my works IDK certification stuff, I set it to AC for sure, I even did it again after watching a movie a couple hours later just to confirm.

The pin numbers are 9 and 10. I measured across those.

I also included pictures from the manual of the circuitry and board.

I feel like I've clearly done something wrong, but I don't know what it is.

[JohnCT]

Originally Posted by TrllVl90

Hey John,


Yeah the meter gets calibrated everyb6 months for my works IDK certification stuff, I set it to AC for sure, I even did it again after watching a movie a couple hours later just to confirm.

I've never seen a Fluke TRMS meter not read accurately on scan derived filaments, but then I've never used that particular meter either..

If you can borrow a scope, you can measure the p-p of the pulse, should be 22V.

What was the value of the original retrace cap and what is the value of the one you installed? (I might have missed that)


John

[jr_tech]

Originally Posted by JohnCT

I've never seen a Fluke TRMS meter not read accurately on scan derived filaments, but then I've never used that particular meter either..

The 114 is an electricians model...some compromises may be made to reduce/eliminate ghost readings.

https://www.fluke.com/en-us/product/...ters/fluke-114

Looks like TRMS readings are only specified to 1 khz... might be way off at 15 khz.

jr