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 Post subject: Proton 619 service completed! Can’t see pluge pattern...
PostPosted: Apr Fri 12, 2019 8:06 pm 
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Joined: Oct Thu 26, 2017 5:04 am
Posts: 69
I finally got a chance to go through the monitor alignment procedure for my Proton 619 TV. If you consider Heathkit to be the gold standard for easy to follow service manuals, the Proton service manual I acquired would be a close second. The procedures were detailed and clear, and I was very pleased with the result of the alignment. This is the first time I’ve used an oscilloscope to aid with TV alignment and it was fun to see the video signals. The comb filter adjustment required displaying a SMPTE color bar pattern and adjusting a pot and a coil “until the subcarrier on the step is reduced to minimum.” Using the same color bar pattern, pre-tint and pre-color adjustment for the automatic picture control required displaying the B-Y demod output and bringing “the top of the blue, cyan, and magenta arrays in line,” as well as adjusting the amplitude to 2.5Vp-p.

The only thing that’s a little off is the black level adjustment. I’m using the Video Essentials DVD and I was barely able to see the above-black line in the low-APL pluge pattern with the black level and picture controls cranked all the way up. With the high-APL pluge pattern, I can’t make it appear at all. I’m guessing this is a symptom of the weaker guns I measured in a previous post.

The picture looks pretty great for a 30+ year-old set, so I might just leave it as is. If I did want to take a shot at increasing the overall black level, would I do that by turning up all three RGB bias controls? Would this then require me to readjust the drive controls and the screen control as well?


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 Post subject: Re: Proton 619 service completed! Can’t see pluge pattern...
PostPosted: Apr Fri 12, 2019 9:33 pm 
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Joined: Apr Sat 06, 2013 2:18 pm
Posts: 476
Location: New Hampshire
Protons were pretty cool sets & high end so rare. I did contract work for a Proton ASC
so got to work on a few. They were well built & good looking. The design was always
one or two generations old so you didnt get the latest. Probably due to that the
picture was right up with the best. I always found it pleasing & natural unlike some
other TOTL sets. Easy on the eyes.... Also they were easy to fix & predictable. Just
dont loose those big long back screws, you wont find another.

Story. At my main gig we took a 27" Proton for disposal. The boss wanted to junk it
being to him a 3rd world chassis & ugly. I told him no way & there was a cult following
for them & they were good sets. I put it on the floor at $300 & shortly a dude came in
& had an orgasm over it. Made a cash deal in the $200 range. This is when we couldnt
get $100 for a perfect used 27" Sony Wega.

73 Zeno 8)
LFOD !


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 Post subject: Re: Proton 619 service completed! Can’t see pluge pattern...
PostPosted: Apr Fri 12, 2019 11:47 pm 
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Joined: Jan Thu 01, 1970 1:00 am
Posts: 240
Location: madison,wisconsin
Turn the Picture control way down, then look for the Pluge, if you have picture Control all the way up you will not see it


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 Post subject: Re: Proton 619 service completed! Can’t see pluge pattern...
PostPosted: Apr Fri 19, 2019 5:54 am 
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Joined: Oct Thu 26, 2017 5:04 am
Posts: 69
I took off the smoked glass panel in front of the CRT and cleaned everything. Then I tried the adjustments again. Regardless of where the picture control is set, low, medium, or high, I am unable to see the pluge pattern. The only time I can barely make it out is with both black level and picture at the maximum setting on the low-APL pluge pattern.


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 Post subject: Re: Proton 619 service completed! Can’t see pluge pattern...
PostPosted: Apr Fri 19, 2019 10:42 am 
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Joined: Jan Thu 01, 1970 1:00 am
Posts: 240
Location: madison,wisconsin
Electronizer wrote:
I took off the smoked glass panel in front of the CRT and cleaned everything. Then I tried the adjustments again. Regardless of where the picture control is set, low, medium, or high, I am unable to see the pluge pattern. The only time I can barely make it out is with both black level and picture at the maximum setting on the low-APL pluge pattern.


What Generator you using? I have several, my main is a Quantum data 680 and some Sencore series made for them by Quantum data
I have never ran into a problem not being able to see the pluge pattern, but maybe your CRT is in that bad of shape and not allowing for any setup level
maybe check to see if there is any type of AGC control or circuit that is set too high also does the Video in have a 75ohm termination switch? maybe check to see if the input termination is ok,

Terry

Oh I re-Read your first post, I see you are not using a calibration generator, you are using a DVD, I have always used high end Calibration Generators, I am not familiar with what pluge pattern they have on that disc, or the levels
but still check for proper termination and internal gain Settings, maybe use a CRT Tester and see what the Cut off levels are for each gun, if those are good then start digging into the Video area, bad/High ESR caps in high heat areas


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 Post subject: Re: Proton 619 service completed! Can’t see pluge pattern...
PostPosted: Apr Tue 23, 2019 10:11 pm 
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Joined: Oct Thu 26, 2017 5:04 am
Posts: 69
Terry, thanks for the info! Yes, the guns are a little weak on this set—all tested in the yellow area on my B&K 470. I was able to see the pluge pattern after I turned up all three RGB bias controls a little and recalibrated the white balance. My understanding is that the bias controls affect the low intensity or background parts of the picture, and the drive controls affect the highlights. So, that’s why I adjusted the bias to see if I could make the pluge pattern visible. However, I also think I read that the screen control affects the background. So, I’m wondering if it’s better to raise the RGB bias controls or to use the screen control to increase the background level, or if there’s no difference. I’m guessing either approach will shorten the life of the tube.

Anyway, now the picture looks great!


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 Post subject: Re: Proton 619 service completed! Can’t see pluge pattern...
PostPosted: Apr Wed 24, 2019 1:09 am 
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Joined: Jan Thu 01, 1970 1:00 am
Posts: 722
Location: dayton oh usa
i lean towards running bias low and screen higher.
weak crt tends to smear on bright colors.
it is less a problem with rgb bias low and screen higher to make up the brightness.
some sets like 80's teknika and mitsubishi were bad for color smear and really beat up their crt's.
i would turn rgb bias all the way down and g2 up a bit.
then touch up bias for greyscale.
sometimes got another year or 2 before customer had to "bite the bullet" and replace tube or set.
in your case i would be on the lookout for modern sets with a physically compatible crt.
these sets are easy to find cheap or free.
this is how i save arcade monitors.


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 Post subject: Re: Proton 619 service completed! Can’t see pluge pattern...
PostPosted: Apr Wed 24, 2019 6:19 pm 
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Joined: Oct Thu 26, 2017 5:04 am
Posts: 69
Thanks kc8adu! I’ll keep an eye out for a free 19” TV. I’m assuming it needs to have the same pinout and yoke impedance as the OEM CRT. Anything else I should look for?

Also, now I’m thinking about adding a pattern generator to my toolset. I see that some of the SAMS photofacts I have list the B&K 1211A, 1249, 1251, and 1260 as possibilities. Any recommendations?


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 Post subject: Re: Proton 619 service completed! Can’t see pluge pattern...
PostPosted: Apr Wed 24, 2019 9:17 pm 
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Joined: Apr Sat 06, 2013 2:18 pm
Posts: 476
Location: New Hampshire
Before getting a pattern generator consider a Sencore VA48 or VA62.
They will do almost anything & dirt cheap now compared to separate
equipment.
Be sure its guarantied all functions work & all cables supplied.
Also it comes with 2 books. A quick set-up guide and a bigger manual.
The manual is almost a TV course in itself.

73 Zeno 8)
LFOD !


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 Post subject: Re: Proton 619 service completed! Can’t see pluge pattern...
PostPosted: Apr Thu 25, 2019 1:13 am 
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Joined: Aug Thu 12, 2010 6:25 pm
Posts: 268
Location: Durham, NC
I got a working B&K 1211A this weekend for $10, and it's just about worth that. Too limited a range of patterns for serious video work, particularly with modern televisions. Its crystal-controlled progressive scan would probably give later SS sets the willies. Probably OK for tube type service work.

_________________
Mark Nelson
A collector of TV signal boosters and UHF converters -- God help me!
tv-boxes.com


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 Post subject: Re: Proton 619 service completed! Can’t see pluge pattern...
PostPosted: Apr Sat 27, 2019 7:29 am 
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Joined: Oct Thu 26, 2017 5:04 am
Posts: 69
I found a 19” Magnavox nearby. According to the schematic it could use one of four different tubes, including A48KRD89X and A48KZL70X. How do I tell if this is compatible with the Proton set?


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 Post subject: Re: Proton 619 service completed! Can’t see pluge pattern...
PostPosted: Apr Sat 27, 2019 1:22 pm 
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Joined: Jan Thu 01, 1970 1:00 am
Posts: 722
Location: dayton oh usa
look through the vents and see if neck is same size as yours.
the one you have is a real common type.
some newer sets have a smaller neck/gun assy.
you can get lucky sometimes and get a tube you can drop in yoke and all.
if not it can be a bit tricky to get good convergence but is doable.
another issue is that some yokes are pin corrected.
if your set has pin correction on board and you have a corrected yoke that is otherwise useable pull the pincusion transformer and jumper the board to bypass.
just did that on a g07 in a mortal kombat.


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 Post subject: Re: Proton 619 service completed! Can’t see pluge pattern...
PostPosted: May Fri 24, 2019 6:51 pm 
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Joined: Dec Thu 06, 2007 11:54 pm
Posts: 2906
Location: Hayward, California USA
Many DVD players cannot display "blacker than black" as in a PLUGE pattern, and/or they have issues with NTSC black level (7.5 IRE) in general.

_________________
Quote: (Antique TV collecting) always seemed to me to be a fringe hobby that only weirdos did.


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 Post subject: Re: Proton 619 service completed! Can’t see pluge pattern...
PostPosted: May Fri 24, 2019 7:39 pm 
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Joined: Jan Thu 01, 1970 1:00 am
Posts: 274
If the black level is too low, try turning up the screen control. As long as it's a small adjustment, and you don't see retrace lines, it should be fine. There may also be a sub brightness control. I wouldn't replace the CRT if it looks good otherwise.

Low black level (with no other problem) is not a symptom of a bad CRT. Signs of a weak CRT include low contrast, poor RGB tracking, poor focus, and highlights smearing to the right.


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 Post subject: Re: Proton 619 service completed! Can’t see pluge pattern...
PostPosted: Jun Sat 08, 2019 10:37 pm 
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Joined: Oct Thu 26, 2017 5:04 am
Posts: 69
Thanks everyone for the advice! I ended up doing a few more tweaks on the set and then I gave it to a friend who is also a vintage computing enthusiast to make way for my new Sony KV-20XBR. He thought it looked great!

Since my last post I’ve been researching DVD players. I got an old Sony player for cheap and am using that now with the Video Essentials DVD. I also found the service manual for this Sony DVD player. It shows how to enter service mode and set the player to display color bars, and then allows for adjustment of the voltage difference between the sync tip and white level, which it says should be 1V.

ChrisW6ATV, what types of issues do DVD players typically have with displaying black?


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