CROSS Pattern Line Width

[chf1971]

Two Video's link -

https://drive.google.com/drive/u/0/f...bwmC6gf1L4Syyy

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[chf1971]

Yes, the TUNER.
It is the VHF only one. No UHF. I was quite hesitant in removing and working on this , seeing that only VHF channels 03 - 04 would be used for the remote DTV converter or VHS / Beta deck.

Slow hours cleaning and lube. TUNER.
Light engine degreaser on tough spots , mild dish soap and H2O , 99 % isopropyl throughout. Lube / Clean w/ CRC QD Electronic Cleaner followed with CRC 2-26 Lubricant.

Channels 03 / 04 verified operational with DTV converter set top box / O.T.A. Programming Received.

[Notimetolooz]

I would not use engine degreaser. Any oil on the tuner chassis helps avoid rust and corrosion. You don't want to overdo cleaning. especially in areas that it does not effect performance.

It occurs to me that Predictas have a plastic cover on the CRT front.
Is this plastic clean and in good shape?
There could be deterioration and/or mold on it.

Your VA62 needs adjustment, but it is a very complicated unit. Probably more needed than just adjusting the line width. I'm saying that if one adjustment is off there could be other adjustments to check controlling other test outputs.

[chf1971]

Originally Posted by Notimetolooz

I would not use engine degreaser. . . .
It occurs to me that Predictas have a plastic cover . . .
Your VA62 needs adjustment, but it is a very complicated unit. Probably more needed than just adjusting the line width. I'm saying that if one adjustment is off there could be other adjustments to check controlling other test outputs.

Agree. Yes. Definitely Agree.

[chf1971]

Originally Posted by zeno

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

73 Zeno
LFOD !

Agree . I have recently noticed the same, only with the Sencore VA62.

[Penthode]

Did you adjust the fine tuning for brightest picture or best detail before the noise creeps in? The carrier is to sit at 50% of the Nyquist slope.

In this age of digtal televisio and digital compression, the tuning to 50% on the slope on one side of the response is for vestigial sideband reception, a bandwidth saving technique. the trade off was a loss of 3dB signal to noise to get more picture detail though a narrow channel.

It seems that many of the younger folk are not aware of this and I am curious if you have adjusted the fine tuning correctly for best picture detail?

[Kevin Kuehn]

If you ever run across a tuner that has an RCA phono plug connection as the IF output, make sure to verify that connection is solid, including the center pin. Often the outer portion is so solid and yet the center loosens from constant vibration from changing channels. I recently about drove myself crazy trying to track down an intermittent noise disturbance that I assumed was dirty tuner contacts, because bumping the channel would usually bring the signal back. Finally after cleaning and retentioning that center socket on the IF phono jack the problem was solved.