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  #1  
Old 05-22-2013, 05:08 AM
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cwmoser cwmoser is offline
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ETV Workshops ...

I did not attend the ETV this year -- family issues.
But, I was wondering how the Workshops turned out?

Really would be interested in topics oriented more toward current
restorations -- i.e. love to see one on practical TV alignment.

Carl
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Old 05-22-2013, 05:57 AM
snelson903 snelson903 is offline
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Quote:
Originally Posted by cwmoser View Post
I did not attend the ETV this year -- family issues.
But, I was wondering how the Workshops turned out?

Really would be interested in topics oriented more toward current
restorations -- i.e. love to see one on practical TV alignment.

Carl
im interested in that subject to, i would like to see it done for I.F. / R.F. croma color conv. how the factory setup's are step by step to there spec.
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Old 05-22-2013, 11:13 AM
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marty59 marty59 is offline
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I recall after last years convention the subject of IF alignment was mentioned. But I would imagine trying to pull that off in a short timeframe would not be practical due to the complexity and all the steps and equipment involved. I believe most of us understand that this is an area you don't attempt unless you know completely what you are doing and determining if it's necessary to begin with.

Most times regular troubleshooting will suffice without the need to perform any IF alignments. I wouldn't mind going through the steps and knowing how to capture waveforms for comparision just to understand further what I'm looking at from someone more experienced at this than myself.

IF's were always presented to me as taboo with the shops I had been around with back in the day. Although in high school electronics we did attempt an alignment using a B-K 415 on one student's set and the results were not much better than before we started!
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Old 05-22-2013, 11:57 AM
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miniman82 miniman82 is offline
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I have wanted to do the IF workshop for 2 years now, but the time required to explain it all would take an entire day. Some day I'll get around to actually making a DVD of how to do it, but even that might not be enough. You have to remember that each chassis is different, and so are the specs. I suggest that any of you who are interested in learning the 'dark arts' go buy a 415, and play with a chassis you don't care about. Follow the manual on how to do it, once you learn how the 415 works it's a snap to set up an IF chain. I recall the shango did a bunch of videos on youtube on how to do an alignment, but the other problem is videos are hard to follow.
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Old 05-22-2013, 12:16 PM
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DavGoodlin DavGoodlin is offline
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Long ago, I did an IF alignment on my RCA CTC16E (GF681) using the RCA marker, sweep generators and RCA scope per RCA factory service manual.
As Marty59 said re IF alignment, I was expecting huge improvement but my results were unremarkable.

The WWII-era guys I worked for/with always said IF alignments were unnecessary unless someone else diddled with it first. Also need a touch-up if you replaced a trap, stage coupling transformer.

Though I sold my marker and sweep gens, I wonder if a Sencore Speed-aligner would help get the job done?
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  #6  
Old 05-22-2013, 01:07 PM
old_coot88 old_coot88 is offline
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Quote:
Originally Posted by marty59 View Post
...IF's were always presented to me as taboo with the shops I had been around with back in the day. Although in high school electronics we did attempt an alignment using a B&K 415 on one student's set and the results were not much better than before we started!
Poor results with IF alignment can be due to overcoupling the input. Just a half turn of wire taped around the mixer tube gives adequate injection with minimal circuit loading. Then attenuate the genny down to the level that still gives a stable trace on the scope. And you should be good to go.

The 415 is an excellent instrument (or was back in the day).
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  #7  
Old 05-22-2013, 02:11 PM
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Phil Nelson Phil Nelson is offline
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Quote:
Originally Posted by miniman82 View Post
videos are hard to follow.
Video has its place, but it's a terrible medium for explaining complex abstract topics. A printed explanation can include diagrams, etc., and it lets the reader quickly flip back & forth to cross-reference or clarify a point. Alignment is not like baking cookies, where you can watch a short A-B-C video and then easily perform the whole procedure. If it were that simple, we'd all be experts already.

If you want to teach alignment, I'd recommend writing a series of lessons as web pages. Very few parts of that discussion require moving pictures (or even benefit slightly from them). Take setup, for instance. A learner gains little by watching a shaky movie of someone clipping an oscilloscope probe somewhere under a dark chassis. In print, you can show them that part of the schematic with the test point clearly marked, followed by a clear close-up photo of the probe clipped onto pin 3 of tube V21 or whatever. They already know that you hold the probe in your hand and move it toward the chassis before fastening it, so a movie showing that act is an annoying waste of their time.

In a spot where it's important to show something dynamic, you can embed a short video clip in the web page. For instance, I can imagine a short video of a scope screen showing how waveform A changes shape as you turn adjuster B.

Just my $0.02.

Phil Nelson
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Old 05-22-2013, 05:55 PM
snelson903 snelson903 is offline
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Quote:
Originally Posted by Phil Nelson View Post
Video has its place, but it's a terrible medium for explaining complex abstract topics. A printed explanation can include diagrams, etc., and it lets the reader quickly flip back & forth to cross-reference or clarify a point. Alignment is not like baking cookies, where you can watch a short A-B-C video and then easily perform the whole procedure. If it were that simple, we'd all be experts already.

If you want to teach alignment, I'd recommend writing a series of lessons as web pages. Very few parts of that discussion require moving pictures (or even benefit slightly from them). Take setup, for instance. A learner gains little by watching a shaky movie of someone clipping an oscilloscope probe somewhere under a dark chassis. In print, you can show them that part of the schematic with the test point clearly marked, followed by a clear close-up photo of the probe clipped onto pin 3 of tube V21 or whatever. They already know that you hold the probe in your hand and move it toward the chassis before fastening it, so a movie showing that act is an annoying waste of their time.

In a spot where it's important to show something dynamic, you can embed a short video clip in the web page. For instance, I can imagine a short video of a scope screen showing how waveform A changes shape as you turn adjuster B.

Just my $0.02.

Phil Nelson
i agree ,i would like to see one section at a time [ in detail ] like I.F. from schematic to equitment like 415 to chassie hook up to all the effects of adjustments ,and the person to stay on topic while he showing not to wonder off on somthing unrelated ,is there any factory training videos that they used when they were sent to one or two day factory training school ,or did the tv industry do that ,G.M. used to send us to training school for new product or more certifaction ,maybe the larger comp. like zenith or rca might had some program like that.i know all the car / truck industry did i always like the free schooling GM encourged everyone to atend the enginners / and instructors love to talk after class about there product.
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