ROCKFORD PRO 301 SP a bad right channel (burns TC11)

[josesony68]

Hi, I have passed this stage, rockford damaged, what happens is that the Q215 or TC11, came burnt, and try to change it, jump again, when more than half of the course entry level, then your temperature rises in a spectacular way to just frying, but if not exceed that tour, its operation is normal (at low volume, of course) the power, well, I suspect the U1 and U2, to test them any pin negative voltage has given me, any help? Thanks in advance.

 

[josesony68]

rockford 301S help!

Hi, I have passed this stage, rockford damaged, what happens is that the Q215 or TC11, came burnt, and try to change it, jump again, when more than half of the course entry level, then your temperature rises in a spectacular way to just frying, very hot TC2, TC3, TC10 and TC11, but if I continue up the volume just burn the TC11, and after being burned, I have in the speaker output for that channel 29V! while the other channel is working well, any help? Thanks in advance.

please Perry are out there? can you help me?

 

[Perry Babin]

I read it but there's a bit of a language barrier. I couldn't quite understand what you wrote. Try writing it as you normally would and running it through a translator like the one google offers. Between your translation and the google translation, I may be able to understand.

When referring to the transistors, use the circuit board designations silkscreened on the circuit boards, not those on the insulators.

 

[josesony68]

Perry forgiveness, I said in the post, I have burned this stage, the Q215 was short and the audio output is 29V. I have twice changed, and what happens is that, when plugged everything is fine, but when trying to climb a little volume of audio input, heated very quickly Q115, Q119, Q219 and Q215, the latter is the burns, and the other channel is still running, I'm a little confused, any ideas?

 

[Perry Babin]

Did you check or reset the bias?

Does it heat up with no input?

Were the transistors soldered to the MEHSA insulators and were they clamped to the heatsink?

 

[josesony68]

Did you check the bias? What do you mean by that? transistors are good soldiers and when there is no input, do not heat anything.

 

[Perry Babin]

The bias current determines the idle current through the output transistors. You set it with the bias pots.
http://www.bcae1.com/temp/ausettingbias.swf

Did you solder the transistors back down to the MEHSA insulators?

If so, did you tin the backs of the transistors before doing so?

 

[josesony68]

agreement, Perry, I did not know that those two adjustable resistors were to regulate it, only seen them in such small stages, Now I have to go to work, this afternoon, I look and I tell you what happens, greetings. (yes, mosfet, are well soldered to the MEHSA, only one, which I removed).

 

[josesony68]

Sorry Perry, just to test the stage, adjusting the bias, and re-burn the Q215 (IRF540N) even putting the pot to a minimum, was still warming up fast, coming up the input volume, the other channel, however, is correct and until Monday, I can not buy the transistor, this electronics store does not open on Saturdays, so until Monday I can not go ... regards

 

[Perry Babin]

The IRF540N is not generally a good sub for the original IRF540. This may be the reason it's failing.

 

[josesony68]

I agree, try to buy IRF540 (I think this store does not) I'll look for another store, when I get it and weld, I'll tell you what happens, thank you very much and best regards. Ah, I forgot, I might have to also help with a 1501bd I will pass ....

 

[josesony68]

Hi Perry, it appears that after searching, I find the IRF540. Would it be possible, Perry, switch the two? (IRF540N and IRF9540N) these if available. ¿Look good, or would cause failure?

 

[Perry Babin]

You can use the IRF540 to replace the IRF540N. I don't know if the 9540N causes problems or if it needs to be replaced.

 

[josesony68]

No, I was wondering if you could do the reverse, the IRF9540 not cause failure, but as I find the IRF540, if I had thought these two could be replaced by IRF9540N and IRF540N respectively.

 

[josesony68]

I say the contrary (this google translator does not translate well) IRF9540 works well, but I said, remove IRF9540 and replace for IRF9540N and next, where was the IRF540, put the IRF540N .... What do you think?

 

[Perry Babin]

I would not use the N-version FETs in place of the non-N version FETs. The non-N version should be a good sub for the N-version of the FET but that may not be true in every amplifier.

 

[josesony68]

Ok, I keep looking at other stores to see if I find you (I will ask because IRF540N IRF9540N and very well located in the stores around here) you know a store to send to Spain? Thanks Perry.

 

[Perry Babin]

Búsqueda de productos | Farnell España

 

[josesony68]

Thank you very much, Perry, I'm going for a two week vacation, when I return, I think I will have the transistor .... I'll tell you. regards

 

[josesony68]

Hi Perry, I found the IRF540 and I've welded and fixed to the Mesha, but now where do I connect the ends of the tester to adjust the bias? (I know they are 50mV for each FET of each channel)