Re: CAr amplifier input sensitivity
Well, this post is over a year old, and basically no responses at all. It's pretty disappointing that over 370 views nobody gave a damn to answer... Badcaps is not what it used to be 13 years ago when i opened an account here. I managed to solve this problem by myself, but still, disappointing.
forgonati
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Last Activity: 10-28-2023, 05:31 AM
Joined: 10-24-2010
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Re: Marantz NR1501 HDMI Board CHK CPU Error
Hi guys! I can confirm the C1604 cap too. I have a 1501 which had an intermittent audio problem. I had audio in pure direct mode, when DSP board is bypassed. In normal mode no audio, or only rarely. Changing the C1604 seems solved the problem.
Thanks for [B]mg37[/B] for the solution.Re: Marantz NR1501 HDMI Board CHK CPU Error
Hi guys! I can confirm the C1604 cap too. I have a 1501 which had an intermittent audio problem. I had audio in pure direct mode, when DSP board is bypassed. In normal mode no audio,Leave a comment:
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CAr amplifier input sensitivity
Hi people! I would like to ask you for hints, how to increase the input sensitivity on a car amplifier. My old amp had much higher senstivity (or higher gain) but it was a bit underpowered, and became quite warm. Since it is mounted in a crowded space with little ventilation, i decided to replace it with a bigger one. This one warms up much less and drives my sub much better, everything is fine, but with this amp i have to crank up the volume much more. It's a chinese head unit with pretty low RCA outputs. So i thought maybe increase the input sensitivity on the amp. Here is a picture of the input,...Last edited by forgonati; 04-22-2022, 02:11 AM. -
Re: Medion 42" plasma not turn on
Some good news, i'm done with these hybrid replicas, next week i will install them into the Z-sustain board. I'm very curious, i hope, it will work......Leave a comment:
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Re: Medion 42" plasma not turn on
I do everything myself....Last edited by forgonati; 11-01-2010, 02:47 PM.Leave a comment:
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Re: Medion 42" plasma not turn on
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Re: Medion 42" plasma not turn on
It's not problem rebuild that hybrid. Here is the PDF file, the board layout, everything. It's 100% working....Last edited by forgonati; 11-01-2010, 02:30 PM.Leave a comment:
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Re: Medion 42" plasma not turn on
So, i have good news, the TV is working, even without the Z sustain panel
See attached pic.
Of course, the screen is not perfect, wihout Z sustain.
I let it run cca. 10min, no problems....Leave a comment:
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Re: Medion 42" plasma not turn on
[I]"From the looks of the hybrid, (never saw one torn open before) these are similar to STK genre devices with BMF heat sinks glued on. Yes?"
[/I]
Absolutely. The newer LG plasmas uses on Z and Y boards STK795-811A, for example.
[I]"My schooling taught me to look at the power supply as a prime suspect and make sure it was working correctly. Once that is done, then you can move onto tracing the problem down"[/I]
Agree. I send PM message to Maxxarcade, he has repaired that PSU, maybe he...Last edited by forgonati; 11-01-2010, 01:13 PM.Leave a comment:
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Re: Medion 42" plasma not turn on
PlainBill:
Maybe you're right, and the 24V is absolutely allright. I try to PM to Maxxarcade, maybe he knows the truth about the 32V line.
I was nothing to loose, so i opened up the hybrid. I have 2 FETs blowned, the 2nd and the 4th from left.
I don't understand, WHY these hybrids blows out
I find many many people on the net, who have the same problem. Those crap hybrids... 
Toasty:
The first thing i did, checking all MOSFETs, diodes, rectifiers,...Last edited by forgonati; 11-01-2010, 10:03 AM.Leave a comment:
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Re: Medion 42" plasma not turn on
You're right, it not explains the 32V line, but i have no idea, where is the problem. I have already mentioned, on primary side of the T2 i measured 380V. And on the secondary only 24V. Those big caps (C33, 35, 36) are ok, and those small caps on the other side (C66, 67, 68) are ok. What now? Please give me ideas, on where to look for problems.
I'll explain it again, i have tested the PSU WITHOUT ANY PANEL CONNECTED, and i still have only 24V on the 32V line, so i think, not the audio amp cause the problem....Last edited by forgonati; 11-01-2010, 03:05 AM.Leave a comment:
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Re: Medion 42" plasma not turn on
So, i checked all 4 hybrids on each panel. On Y sustain i measured between Vs and SUS_OUT 5 Mohms. But on the Z sustain i measured only 4,5 ohms on the IC5, so that hybrid is shorted. The other hybrids are OK. So i have 1 shorted hybrid IC. So i need to be rebuild that.
In te next days i order the needed components. I will inform you guys here, when i'm done with the hybrid.
PlainBill, Toasty, thank's for the help
...
Last edited by forgonati; 10-31-2010, 05:07 PM.Leave a comment:
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Re: Medion 42" plasma not turn on
I checked the input voltage of the T2. I measured 380V, so i think, there is enough "drive", and probably those big electorlyts (220uF/450V) are OK. I have no idea, why the 32V is only 24V ...
But i checked, what uses the 32V supply. The 32V goes to the 2x20W audio amplifier IC, LM1876. This IC needs supply voltage 20V-40V (The absolutely minimum is 12V and the maximum is 64V). So, i think, when i have only 24V istead of 32V, this should not cause a problem...
PlainBill:
I checked the part numbers...Last edited by forgonati; 10-31-2010, 10:35 AM.Leave a comment:
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Re: Medion 42" plasma not turn on
I don't know, really. The "32V" is only 24V, so something is wrong on the PSU, you're right.
But when i disconnect the Z sustain, the PSU is working without any problem, but when i connect it, the PSU is shut down immediately. So probably the biggest problem is on the Z sustain. Tomorrow i check the T2 primary side, and i replace those damaged ceramic caps. And i will see, what's happen.Leave a comment:
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Re: Medion 42" plasma not turn on
No, the 32V is still missing, i have only 24V on the "32V" connector. When i disconnect the Z sustain, i still have only 24V. But, when the Z sustain is not connected, the PSU is working perfectly, and i have all voltages, 5V, 5.5V, 15V, 12V, and i have the Vs, Va, Vy and Vsetup voltages also. And the PSU is working. The "32V" is still 24, but i think, the problem is on Z sustain board, probably i have a shorted hybid IC.
Tomorrow i check the PSU one more time, for the missing 32V, but i think, the biggest problem...Last edited by forgonati; 10-30-2010, 05:16 PM.Leave a comment:
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Re: Medion 42" plasma not turn on
So, I checked those voltages. When i have connected all boards to the PSU, the PSU shut down after 2 sec, and i don't have enough time for testing, even with an old analog multimeter.
BUT. When i disconnect the Z sustain board, the PSU is working properly, and all voltages are present. On the "Vs" i measuring 175V, on "Vsetup" 221V, on "Va" 75,2V, on "-Vy" -80,3V. So all voltages are correct (except the 24V) But only, when i disconnecting the Z sustain board... What now??? I have a shorted...Last edited by forgonati; 10-30-2010, 12:03 PM.Leave a comment:
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Re: Medion 42" plasma not turn on
You're right, i found the label, contains those voltages. Thank's a lot.
See attached pic. I check those voltages one more time....
Last edited by forgonati; 10-30-2010, 11:22 AM.Leave a comment:
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Re: Medion 42" plasma not turn on
I have already tested the PSU without any other panels connected, and in the 32V connector i measured 24V, so the problem is on the PSU. Tomorrow i sheck the voltages on the primary side of the T2.
Sadly, i don't see any label with correct Vs, Vy, Vset voltages. So i don't know, these voltages what i measured, are correct or no.
What is your opinion about my last post? When i connect only the Y sustain, the PSU don't shut down. How can i test the Y and Z panel, or those hybrid ICs?
ThanksLast edited by forgonati; 10-30-2010, 10:49 AM.Leave a comment:
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Re: Medion 42" plasma not turn on
UPDATE:
New interesting thing, what i figured out: When i disconnect the Y sustain board from the PSU, so i have connected to the PSU only the Z sustain board, (other boards are connected) the PSU shuts down, and the green LED on the PSU blinks 5x. (would be good to know, what means these blinking codes) But, when i disconnect the Z sustain board, and i connect only theY sustain, the PSU don't shut down, i let it run cca. 30-40 sec, and the PSU don't shut down
So maybe the Z sustain is damaged also, and overload the PSU?...
Last edited by forgonati; 10-30-2010, 09:51 AM.Leave a comment:
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Re: Medion 42" plasma not turn on
Thanks for the detailed explanation!
The model number of the TV is MR 5265. See attached photo. The logic board is from LG, also the plasma panel. The panel model is PDP42WVSN3.
So, in the T2 secondary side i measured 24V DC. The IC11 and IC12 produces voltages 15V and 12V, so they are correct. These voltages (also the 24V) going to the multiplexer IC10. Maybe the problem is there, the 24V is too low, so the PSU shuts down. Anyway, the 18V DC in the IC6 is present.
Tomorrow i check the primary side of...Last edited by forgonati; 10-30-2010, 09:24 AM.Leave a comment:
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