I used ground circled in red
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Re: Db Technologies Cromo 12 amplifier no audio
for +/- I meant more or less because the value ranged from 49.3 to 49.5 il pinera undoubtedly the number 6Leave a comment:
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Re: Db Technologies Cromo 12 amplifier no audio
I checked the voltages of pin N ° 6 and both on the non-working amplifier and on the working one I have a voltage of 49.5 +/- voltsLeave a comment:
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Re: Db Technologies Cromo 12 amplifier no audio
ok tomorrow I'll do this test, now it's night here, the unit is equipped with an analog / digital converter, could that have some problem? or the operational amplifiers? however we take it one step at a timeLeave a comment:
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Re: Db Technologies Cromo 12 amplifier no audio
Sorry, my typo, it is pin #6.
Just put Black probe on ground, red probe on pin 6 of the working unit and non-working unit and see if they are about the same Voltage.
Page 6 and 7 of the spec sheet shows you what the Voltage of each mode should be.Last edited by budm; 10-24-2020, 04:03 PM.Leave a comment:
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Re: Db Technologies Cromo 12 amplifier no audio
what voltage should i have?Leave a comment:
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Re: Db Technologies Cromo 12 amplifier no audio
in the TDA8950TH the pin mode controll is number 6 but I didn't understand what I need to test, if you could explain me in practice thanksLeave a comment:
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Re: Db Technologies Cromo 12 amplifier no audio
https://cdn.badcaps-static.com/pdfs/...6bfeac6d82.pdf
Look at page 22 then check the Voltage at the Mode pin 23 of the working unit and the not-working unit.Leave a comment:
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Re: Db Technologies Cromo 12 amplifier no audio
unfortunately I don't have an oscilloscope but I have the same amplifier so I could do some tests if you tell me what to doLeave a comment:
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Re: Db Technologies Cromo 12 amplifier no audio
Since you are not getting the sound form Tweeter or the Woofer, then it is probably something that is common to both amplifiers, such as that both of them are in Mute mode, or the audio signal form input is not getting all the way to the amplifiers.
This is not going to be easy fix. Do you have working board to do Voltage comparison testing?
Do you have audio signal tracer or scope to trace out the audio path from input all the way to the output sections?Leave a comment:
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Re: Db Technologies Cromo 12 amplifier no audio
I also noticed that the final of the tweeter (the innermost one) warms up much more than that of the woofer (the outer one)Leave a comment:
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Re: Db Technologies Cromo 12 amplifier no audio
how can i proceed now?Leave a comment:
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Re: Db Technologies Cromo 12 amplifier no audio
I mounted the capacitors but still no sound output from the woofer or the tweeterLeave a comment:
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Re: Db Technologies Cromo 12 amplifier no audio
ok I'll update you tomorrowLeave a comment:
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Re: Db Technologies Cromo 12 amplifier no audio
tomorrow I will try to solder the capacitors to understand what happens, I keep you updated, I preferred to do the tests you asked me to avoid burning the power amp as I ordered it from china and I had to wait 2 weeks before receiving it, let me know also how should I behave with the inductors if you think they are okay or I have to replace themLeave a comment:
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Re: Db Technologies Cromo 12 amplifier no audio
So right now either one of them are working?
That shorted out filter cap should not affect the operation of the unit once it is removed.Leave a comment:
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Re: Db Technologies Cromo 12 amplifier no audio
woofer and tweeterLeave a comment:
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The Problem: This player has a toggle switch to select between Stereo, Mono R, and Mono L. Regardless of the setting it outputs the sound to both the L&R audio jacks. In the Mono R position, the audio output level is normal (from both the L and R audio output jacks), in the Stereo position the audio output is about half the volume, and in Mono L, it's about 3/4 the volume. Something about putting it into Stereo mode is causing the volume to drop significantly and I can't figure it out.
The player processes the audio signal using two different reference frequencies. The "R"... -
Well for RF transmitters, transmitting without an impedance matched antenna and if the transmitter doesn't have automatic limiting... kiss the final transistor goodbye and chalk one up to something you killed.
But that's not the same way with audio amps for the most part, well, at least the wavelength of audio on copper is so long that you get all of it back anyway but the transistor is fine with it...
So how are people destroying finals in their audio amplifiers then? Heh.
Are people shorting their outputs or something, overdriving output to a too big speaker?... -
My childhood best friend was killed about 9 years ago. His parents are finally letting go of his things, and they offered me his Polk RTi100 tower speakers. The Polk RTi100 towers are one of a handful of designs from the early 2000s that is a full range 3-way tower with a built-in self-powered subwoofer. This is accomplished with a plate amp integrated into the speaker input panel.
I think they used them for a while, but they've been sitting for at least a few years now. After about 40 hours of driving to their house and back (both they and I have moved in the last 9 years) I got... -
I found a project in the electronics trash yesterday. A nice Argon SA1 audio amp with some electrical issue. Took it apart and saw that the 4A250V fuse was blown so started lifting components to find the short. Eventually got to two MOSFETs (model FTA14N50C) that are shorted and when i took them out the short was gone.
Now i didn't have any replacements of the same model of course but i found a couple with pretty similar spec i thought (K10A60D & K12A50D) and put them in. Also replaced the blown fuse with a 3.5A250V one. Checked another time for short circuit and plugged it in.... -
My boss always says "the only stupid question is the one not asked" so at the risk of asking a stupid/obvious question I'm going to one any way...
I've got a pair of speakers with an amp built in to them in for repair and on inspection I can see the TDA2030A amplifier ICs have blown (so I've ordered some spares which should arrive soon):
My quesion is with regards to the white paste you can see on the TDA2030A and heatsink, I'm assuming this is just some thermal paste and if so is it a special kind or will the grey thermal compound that I have...
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