When I connect cable:
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TV and Video
Fall TV
2.085
hace 6 años
hace 6 años
Philco PS2914
This tv had the damaged jungle (it was seen in black and white). It was from a client who had brought it to me a while ago, which tells him what the problem was, but at that moment he gave up, since he was satisfied with looking at B & N before waiting a few days for the spare to arrive. It is seen that I take it to another technician, and go to know what happened, the question is that I arrive without the jungle, I surely take it out to ask for the spare part. Well, I put the new jungle, but this was seen with a vertical strip on the black side of about 3cm. The tuner did not work. He looked rainy as soon as he could see even the silhouette of the images. I went back to change jungle thinking that it was the same problem of tuning, borrow another TV, with this vertical black stripe disappeared but the problem of the sinto persisted. Well put a new one today, AV works in color, but the synth does not show signs of working, it is in the same situation. Put another memo, put a virgin, program it, and nothing. What could have failed? Since the synth does not even touch it, I'm thinking about the tuning coil that is very close to the jungle, but still I did not want to touch it.
Another synth and another SAW filter were placed. The fault persists.
Tensions in SINT:
AGC: 4v - CLK: 3.6 / 3.9 variables - DT: 3.6 / 3.9 variables - MB and PB: 4.9V - TB: 33V
When I connect the cable, it is seen that it takes the signal, obviously distorted, so it is seen normally (without connected cable):
When I connect cable:
When I connect cable:
2.308
hace 6 años
It's a good idea about the trimmer. Many teachers recommend it. I commented that when we have placed the capacitor, we have never been tuned well. change channel, you see some stripes and stabilizes thing for three seconds but it shows. Maybe some companion in your town can provide capacitors for some chassis. Comment if you tried the channel selector and if the signal is seen on another tv. Greetings. felipe ascencio
2.085
hace 6 años
Yes, the same thing happens to me, I was more than 3 hours to see if I put it to point and do what you say, when you change the channel you see, at half a second it "tunes" and then the image remains. But well, I said enough and I remain like that, I would say 95%. You decide that placing a coil of another chassis, it will be fine? only for curiosity. regards
2.308
hace 6 años
partner. when placing another coil, what we have achieved is that time is reduced to tune, but nothing at 100%. if you have achieved 95% it is not good, it is excellent. it's good that you've achieved it Congratulations. Greetings. felipe ascencio
2.308
hace 6 años
hace 6 años
suggestions. you remove the channel selector. and with a tv bn that has input transformer, you connect the ground wire of the bn to the ground of your color tv. Pin the channel selector fi bn you take a cable and connect it to the pin of your TV fi color through a capacitor ceramic .047uf, you tune the bn and the image has to see on your color TV. in this way you can check that the jungle fi channel is working. In the electronic community there is a diagram of a channel selector and how to provide its voltages so that you can use it as an injector in the fi tvs of color. I hope you find it useful. felipe ascencio
2.308
hace 6 años
and what was the result? .- This way is what we use, we have already prepared a channel selector of those mechanical "turret" of a tv bn. you can also assemble a peak-to-peak voltage probe, there are two options, one like the one in electronic community but using glass diodes since these support 50vcd maximum, or using the picerno ing probe, we have armed both with good results So in the jungle you can see which is the video output pin and place the probe and measure if you have vpp. (peak to peak voltage). comments .saludos. felipe ascencio
2.308
hace 6 años
The problem may be the jungle. but before changing it, check the voltages and weapons of the ingpi vpp probe so you can see if you have video output on the corresponding pin. place the selector and try to pass the color fi signal to tv bn. If you do not have a signal generator, in a cyber you can make one, you connect it to the antenna by means of a DVD. so you can have the fixed video output. Tell us what the jungle is, in case we have some similar diagram. Greetings. felipe ascencio
2.085
hace 6 años
The diagram is this: http://www.archivotecnicosaurios.com/descargas/tv/seccion_ordenada/9810_Chassis_LA5-A.pdf
2.308
hace 6 años
already download the diagram, but you armed the vpp probe ?. the image stops being seen, but the sound is left or lost. Check with a logical probe the data bus (or pulse train) of the memory to the channel selector. in an electronic community there is a probe which is useful because it has low pulses, high pulses and pulses. On Saturday we will look at the diagram and try to provide more information. Greetings. felipe ascencio
2.308
hace 6 años
the diagram that you indicated has the jungle la76818am. as for the selector if possible with the voltages that "pass" the color tv signal to tv bn. In elpin del agc place a regulator 7805 so you can vary the voltage of 1.5 / 3.5 vcd. with this we will leave doubts about the selector. with the vpp probe check pin 46, it should have 2.5vpp. and in pins 19,20,21, it should have 4.6 / 4.8vpp. Greetings. felipe ascencio
2.085
hace 6 años
By measuring everything and finding it right, I went for my first suspicion, capacitor VCO coil. Take out the capacitor, and connect the coil alone, and to my surprise I already tuned to color, but without the capacitor it was not perfect, I tried it with a 29p, it only had color in one point, followed with a 22p, I improved, but the same story, from here I jumped to 9pf which was the value that I had at hand, not its intermediates and I improve a lot, but not perfect, I will have to try 15pf and 18pf, maybe the channels are stable, but they have rain and audio interference.
2.308
hace 6 años
it's good that little by little you are achieving it. we have a sanyo diagram in which the condenser that has the vco coil, we place it from 18 on the outside, that is, we place the coil and on the side of the chassis we place the condenser, just a couple of tweaks. There is a document in the network about how to work with that coil. Greetings. felipe ascencio
2.085
hace 6 años
Yes, that's what I was doing, but I just do not have the intermediate values to those, in addition to the coil the touch, since I just got the plate of that TV, so I said, as a last resort I try to move the coil, so what I did and saw some image after giving it about 4 laps. Disarm, take out the capacitor and connect it with nothing and gave me an image, but not perfect, so I tried with capacitors but with no improvement compared to the single coil. So I think directly using a trimmer (variable capacitor), what do I decide? Now spend 3 full hours trying to alternate capacitors.
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