Questions tagged [tv]

Use this tag for technical aspects of TV (video formats, for example). Shopping questions are off-topic and repair questions might be too localized.

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41 views

CRT TV severe geometry issue [closed]

I just got a Sony trinitron wega KV-34XBR970. I heard these flatscreen crts were supposed to have geometry issues but this is a bit excessive. It seems to droop down on both sides and all of the edge/...
4
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2answers
575 views

What makes “quality” analog AV cables better than cheap cables? [closed]

I want to upgrade my retro game setup from a mix of composite and RF to a mix of S-video and component, with some composite for the really old stuff that doesn't support S-video. How can I distinguish ...
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2answers
162 views

Horizontal overscan on NTSC

How much horizontal overscan is there on a typical NTSC CRT television set? Vertical overscan, there are nominally 240 scan lines per field, of which you can reasonably count on having slightly more ...
2
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1answer
83 views

Identifying SMD component 22P W8

I've been trying to identify a component on a main board for a TV that I believe to be faulty. As I haven't been able to come up with anything that I feel confident about, I'm hoping to get some ...
1
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1answer
560 views

Philips 26PF5321 backlight mod, dim backlight

Got this older Philips 26PF5321 LCD-TV, like it because it is not a smart-tv. What I dislike about this TV is the fixed backlight setting (cannot change it via software menu and there is no update ...
8
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2answers
1k views

Circuitry of TV splitters

I'm trying to understand the circuitry of TV signal splitters and associated boosters/amplifiers, and I have two questions. My situation is as follows. I have a TV aerial (antenna) in my loft. It ...
0
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1answer
98 views

LED strips for TV

My LCD back-light strip has broken (LEDs exploded) so I want to replace the LEDs. I measured the output of the wire that act as source for TV strip, it yields 35 V, so am asking if I can take the ...
6
votes
1answer
9k views

What is the function of “Picture tube charger”?

There is a bizzare device called picture tube charger or CRT-Charger. Here I attach the some diagrams of it from a circuit-book. Now, what is its function? what changes it create inside the CRT? ...
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2answers
801 views

How to convert S-video to YPbPr?

I want to connect devices which output S-video (Y/C) to my TV, which only has YPbPr component inputs. One of them outputs PAL (European) while the other outputs PAL-M. One way to do this would be to ...
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1answer
92 views

Where can I get a display screen with 30 Hz or less refresh rate? [closed]

I am experimenting with a camera recording a display screen. Based on what I have read - camera recording a screen will have flicker if the refresh rate and frame rates are not synced. My mobile ...
1
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2answers
94 views

Project - How to onstruct a circuit to introduce and control a 0-300ms delay in an RF feed from a Sky Box to multiple TV sets? [closed]

Just bought a new TV! It's "smart" but where my previous dumb TV didn't, my smart TV introduces a delay over HDMI from my Sky+HD box compared to the RF2 output which is wired via coax cable to the ...
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2answers
454 views

Adding a headphone jack to a TV

I'm trying to understand how I would add a headphone jack (audio out) to a TV of mine. The board on the TV looks like so: And the headphone jack I have is the following: https://www.adafruit.com/...
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1answer
218 views

What does a TV receiver circuit look like? [closed]

I found a few circuits for TV transmitters, but no receivers. I've looked at other simpler RF transmitters and receiver, but it's not obvious to me how to reverse the circuit that I have. I want ...
3
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0answers
2k views

CRT TV NOT TURNING ON [closed]

I'm a beginner in electronics repairing and I need help troubleshooting a tv which doesn't turt on, neither the power LED lights up. The board is a cheap chinese (check the attached image). When I ...
3
votes
2answers
14k views

Philips/Magnavox LCD TV Service UART / ComPair

I have a Magnavox 42MF438B/27 42" LCD TV. The IR sensor (or something related) quit working after awhile, so we have been unable to use the remote. Today, I was digging around behind the TV and ...
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2answers
161 views

TV capacitor 54j 6kv swc [closed]

My television (the brand is Philips) died and I'm trying to save it, When I had open it I had see a dead capacitor (54j 6kv swc), the most similar I saw was on Ali express with (54j 6kv), I don't ...
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3answers
190 views

Two TVs use the same antenna, but one affects the other

I’m having a problem with my TVs. I will call them TV1 and TV2. TV1 is Asanzo brand, and TV2 is LG 4K, which is much more expensive. After replacing the antenna wall socket of TV2 (The TV is near to ...
2
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1answer
530 views

127v 60hz TV to 220v 50hz [closed]

Hi all I recently moved from Mexico to Portugal and brought some electronics I suspect they are multi voltage and multi frequency. But reading the label of a Sony TV I got into doubt if it is or not ...
4
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1answer
181 views

How do we know off-screen area in TV?

I'm trying to implement HDMI to FPGA and vice-versa. Currently I'm referring with https://www.fpga4fun.com/HDMI.html site. But I'm confused that "But video signals usually also have an "off-screen" ...
5
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1answer
122 views

How do LCD screens repair themselves?

Hey, electronics people: A few months ago, I cleaned a spot on an LCD flat screen. Whatever it was, it was stuck on there pretty good and I guess I pushed down on it too hard (actually wasn't hard at ...
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1answer
62 views

Question about how the circuit of TV display works

I have a question about how the circuit of TV display works. Does current flow through the gate lines (horizontal lines)?
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1answer
54 views

UHF TV transmitting circuitry [closed]

I would like to know your opinion what are existing solutions for building a small (<5W) UHF TV transmitter. The problem is every circuit or schematics I find already uses separate audio/video ...
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1answer
111 views

Is this tv wire dangerous? [closed]

Hi I needed a tv for my ps2 and GameCube as they look blurry on HD TVs, I dug this tv out of the spare room but unfortunately whoever put it away just dumped it there without paying attention to the ...
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2answers
1k views

Do BAD capacitors work less in the cold?

This might seem a very strange question and I'll try and not make this about fixing my damn faulty TV but I will give you the history in why I'm asking. I have a faulty TV and it repeatedly turns on ...
5
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2answers
2k views

White Dust: Is it bad for electronic devices like smart TVs or phones?

As a side result of using an ultrasonic air humidifier, this white dust thing can be seen on house furniture during its activity. I googled about it but I only found a few articles, saying that it is ...
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1answer
126 views

Can you attach 2 coaxial leads to a single TV antenna [closed]

I would like to hookup 6 TV's to one antenna. The largest splitters only have 4 outputs. Can I run 2 leads from the same antenna each to a 3 way splitter?
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1answer
2k views

Is there a master list of LG TV RS232 commands available somewhere? [closed]

I have a LG OLED65C7P TV and for aesthetics reasons, I'm trying to force the TV to use the analog audio input (multiplexed with composite video input on a 3.5mm jack) for direct analog audio playback ...
2
votes
1answer
77 views

TV display shimmering [closed]

First, a video: longer, higher quality This is a closeup of my TV, of a still picture (the Xbox One menu) There is no motion, the TV has all filtering, sharpening, etc disabled. Could it be that ...
0
votes
1answer
114 views

How to increase the audio power out to amp from tv

I have LG led tv 43lh576t . Im trying to connect the audio system using aux by taking output from tv's headphone out. Audio system doesn't have optical in. The problem is tv's output is very low. Is ...
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3answers
104 views

Is there something to see outside the normal analog TV video frame?

I've heard from TV repairmen and read in various sources through the years that the TV radio signal isn't shown on radio TVs in its entirety. I've noticed that on different radio TVs the same channel ...
1
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0answers
545 views

Does the rt2832u chip have enough bandwidth for ATSC?

I'd like to upgrade the audio/infotainment module in my 2009 Camry. I see several off the shelf solutions, but they don't have a builtin digital TV tuner and the processor isn't as fast as I'd like. ...
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2answers
358 views

Purpose of low voltage pins on TV power switch

I am building an arcade machine, using a CRT television. I am wishing to replace the television's front panel power switch with a toggle switch on the outside of the cabinet but am concerned by two ...
4
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1answer
140 views

What level of a square wave signal should be safe for TV receivers?

I am experimenting a bit with TDR (time domain reflectometry) and for it I am generating a square wave with up to 10kHz and a rise time of about 1-2ns. Now I would like to put that thing to use and ...
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2answers
4k views

TV signal into an Oscilloscope

I'm plugging TV signal cable directly into an oscilloscope. TV cable looks like this: First I connected outer shell of TV cable connector to GND of oscilloscope BNC cable and center to the center of ...
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1answer
75 views

Cost of early color monitor versus TV [closed]

Back in the seventies and eighties, an important design choice for a desktop computer was whether to use a television or a dedicated monitor for display. A monitor could give better resolution; on the ...
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1answer
285 views

LG TV RS232 Control over rollover cable [closed]

My LG TV can be controlled over a RS232 port! The Problem is that I don't have any serial devices to test it. So my question is, can I do it with a rollover cable(RJ45 <--> D9)? I mean can I ...
1
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1answer
85 views

Can I connect TV Speakers to an interface and use them as stand alone? [closed]

A couple of months ago I broke my TV and the only thing I could kept were the internal TV speakers The TV was an LG 55EA9800. Now, my laptop has been giving me issues with the sound, I think the ...
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2answers
2k views

Computer case causing interference with TV

I've recently changed my computer case to a new, bigger case. However, after I changed this case over, I can no longer watch TV due to interference with the signal. I have removed every output to my ...
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1answer
49 views

Can I store all channels from the signal coming from a digital antenna? [closed]

Whatever signal comes out of a digital antenna carries many basic broadcast channels (ABC, FOX etc.) Once this signal reaches the TV, some extraction circuit extracts (or tunes to) the channel I want ...
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0answers
72 views

How could I interpret these-2 YUV modulated picture given in wikipedia? is it correct simulation? or something I'm missing?

While reading the wikipedia article on YUV color modulation (which is used in PAL color tv receivers); I visited this diagram: (Wikimedia); (and according to the image description there; i.e. "...
3
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8answers
16k views

Why there is 625 lines [ PAL ] in T.V. scanning or odd lines?

I can't get why there are 625 lines in a PAL scanning system. I read R.R.Gulatti's standard book. In that there is a reason like: "Suppose there are x lines in 1 field. Then for two field its 2x....
3
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1answer
1k views

What is the function of this cable surrounding the CRT of old televisions

I have opened old televisions, and each time, I'm wondering what is the function of this cable, roughly insulated with some tape. Note: I know what are the risks of opening televisions.
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1answer
344 views

5.5" portable CRT television with several black lines

I have this monochromatic chinese television largely manufactured in the past decade, marketed under several brands (Coby, Curtis, Precision, etc). This one in particular have a external AC DC ...
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1answer
613 views

TV power board not working [closed]

My TV recently broke and I went to get it repaired and they said that the power board had died. I took the TV home to see if I could fix it and everything appeared to be fine. If it is a broken ...
0
votes
1answer
140 views

What does the FP2108T Ic do?

I have disassembled Parts of something (I think it was an old TV or RC controller). There I found an IC with this printed on top of it: "Futaba Japan FP2108T 9175K". I am not good enough that i can ...
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2answers
3k views

What is the purpose of the diodes on a Samsung LED TV backlight bar

Skip to the question below if you don't care about the details ;) The bottom half of the backlight in my TV went off so I opened it up to see if I could fix it. I found four of the 7 bars of LEDs ...
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1answer
66 views

UHF band repeater [closed]

I want to make a device which gets the TV antenna signals and transmits it again. Is there any module available in market which simplifies construction or i should make from scratch? Since my ...
8
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4answers
1k views

TV screen in still photo: Why are there dark, blackish bands?

I was trying to capture the scanning process of a CRT TV screen in a photo. It gave me these dark, broad bands, shown below: Fig. 1 a,b,c I'm trying to understand the cause for this banding. However,...
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1answer
827 views

Strange TV Blue Screen issue on switching on any home appliances [closed]

i have recently purchased Android Tv Box CS928 from Chinese site http://www.aliexpress.com/item/CS928-Android-4-4-kitkat-Rk3288-A17-quad-core-2GB-16GB-2-4-5-0Ghz-100M/1939723909.html The Android TV ...
0
votes
1answer
223 views

How do LCD displays with passive 3D polarize light?

I understand how this works with projectors but I cant find any explanation for LCD displays. From what I understand 2 images are interlaced and displayed at the same time. How is it possible that 2 ...