CROSS Pattern Line Width

[chf1971]

Hello -

Philco Predicta Debutante Television Set

While injecting at the first stage of the Video I.F. section of this TV set, the CROSS Pattern from a SENCORE VA-62 displayed on the screen appears to have a wider Vertical Line than the Horizontal Line.

The DOTS pattern appears on the screen as "dashes" more so than "dots".

Two images, attached.

Can you provide any suggestions of what area of the set to suspect for this display issue ? Are their other test patterns which show this defect or alignment issue ?

[Electronic M]

Put a circle on screen and let's see how it looks. It's probably one of 2 things: more likely width is excessive, less likely video/IF smear.

[chf1971]

Thanks for the reply.

I should of provided some History of the TV Set.
I received it in Original un-touched condition.
On the Main Circuit Board all of the Couplets have been replaced with new Couplets received from "The TVrestorer guy ". On the MAIN Board, several of the Film Cap's in the Vertical Section have been replaced. Only the Couplets have been replaced in the Horizontal Section. Unit's Primary Power Supply Filter Electrolytics have been replaced. Vertical Linearity Potentiometer has been replaced. Video I.F. Board is still all Original. Thus, I suspect that the Horizontal Section can have out of tolerance caps / resisitor components. The Focus Adjustment's, nor any real Alignment Procedures have Not been performed.

Thank you for any of your suggestions.

[old_tv_nut]

What does regular program material through the tuner look like? Any indication of this smearing? (Hope the tuner isn't dead.) (Trying to guess if the signal you are injecting is somehow wrong level,or if AGC is bad or who knows what.)

[Kevin Kuehn]

Wouldn't hurt to try focus and fine tuning.

[chf1971]

THANK YOU for the replies.

Three points provided : Tuner, Test Equipment and Focus.
The TUNER has not been tested. Wait, I did try it one time and it was a use-less test. The Tuner has been disconnected. It needs to be removed, cleaned, evaluated, tested.
The TEST EQUIPMENT - SENCORE VA62 - Highly Likely To Be A Suspect. I have never verified the particular waveform performance of this SENCORE.
FOCUS - It's been a long time since I really was into or onto a CRT.

[Kevin Kuehn]

Sorry I didn't read your initial post very well where you clearly stated you were injecting signal at the video IF. Definitely test the Sencore on a known good TV so you at least have a baseline. Also that Predicta probably has a fixed focus voltage so it's not too likely the issue. Your VA 62 has a video output so you could bypass the IF stage all together and inject video to the video amp grid.

[chf1971]

Sencore model VA62 Video Analyzer Test Equipment with VHF Channel 03 injection with CROSS Pattern into a different TV on Channel 03. The Vertical Line is wider, as well.

images, attached.

[chf1971]

Philco Predicta Debutante

OTA -> DTV Converter Box -> Sencore VA-62 external modulation - > Sencore VA-62 46.75 MHz I.F. -. Philco Predicta Video First I.F. Stage.

Images, attached.

[Notimetolooz]

The VA62 has an adjustment for vertical line width which also effects the dot width.
Be aware that the more units the signal goes through on it's way to the TV the more the video can be smeared.
Try the Multiburst pattern from the VA62, the buttons will turn each bar on or off. If you can see lines in the 2.5MHz bar that is good enough.
The Multiburst bar use a different circuit than the crosshatch pattern.

[chf1971]

Thank You Notimetolooz -

I took a look at the 2.5 MHZ on the Multiburst Wave Pattern injected at Video I.F. Board Front End. It looks fine.

I always intended this PHILCO Restoration to be minimal, up to the point to get the TV Set, generally operational.

With the DTV Converter Box Over The Air Programs that I have viewed on the set, it appears acceptable. I have had the Sencore VA-62 patterns displayed on the unit for 4+ hours operational time, continuously. Now, decision time - how much further to go on this unit.

[zeno]

Hint for generators especially on color sets.
Always run the brite & contrast low. This will give the
cleanest display.

73 Zeno
LFOD !

[Tube TV]

Originally Posted by chf1971

Philco Predicta Debutante

OTA -> DTV Converter Box -> Sencore VA-62 external modulation - > Sencore VA-62 46.75 MHz I.F. -. Philco Predicta Video First I.F. Stage.

Images, attached.

Looks OK, but really soft. Like any video above 2 mhz or so is being clipped. Have you tried out the picture after the video detector? If it's clear there then you could work your way back through the IF, or if it's still soft then you know that you need to work on the video amp.

I'd change all the wax paper caps in the IF strip if they haven't been done yet as they are going to be leaky and it wouldn't take much to have those out of the way.

I'd get the tuner connected also. I doubt there's anything wrong with it beyond maybe some dirty contacts.

[old_tv_nut]

To me iot looks blurry both horizontally and vertically, so maybe a CRT focus issue?

[chf1971]

Philco Predicta Debutante

Most recent changes : few horizontal discrete ( film caps and resistor ) replacements. More adjustments of external controls : Horiz. Hold, Horiz. Frequency, Width, Height, Vertical Linearity, Brightness, Contrast, and Vert. Hold. Very slight adjustment of Horizontal Centering on the Yolk, however, repositioned this back to original position.

Video available of TV Program.

Cross Pattern from Sencore VA/62 analyzer.

Tim on tv show “ Tool Time “ shown - attached - on this Predicta Débutante.

chf1971