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Problem with T3, any ideas to help me explain to iBasso?

post #1 of 14
5/28/11 at 11:55am
Thread Starter 

 

I am using a T3 with a J3.

 

Without headphones or the interconnect to my car plugged in the J3 has no issues (and no value :o)).  As soon as I plug something in the output (in other words try to use it), The J3 battery meter (artificially) goes to 0 and shuts down.  If I plug an output in before I turn on amp, the battery meter shows the accurate charge until I use a function on the amp (gain switch or volume) then it drops to 0 and shuts down.  Battery is not actually 0 boots back up showing full battery and w/o amp runs fine.

 

I use a D4 also and have no such issue,

 

I worry iBasso will think its a J3 issue and start a week long thread of e-mails with me. I do not know electronics so maybe there is a likely cause I can test for or just make a safe assumption and report it back to iBasso to streamline the exchange.

 

Like maybe loop-back, feedback, polarity, short.. I am just throwing out words here :oP

 

Any thoughts on how to test or what is likely?

 

Thanks

 

 

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post #2 of 14
5/29/11 at 2:22am
Thread Starter 

So Ibasso says the J3 must be sending out a DC output and it needs service.   The J3 is the unit shutting down not the T3, how could an output problem on J3 be the issue?

 

Here is the reson they say it is not happening with D4  - Does this make sense if it is the J3 shutting down?

 

 

The T3 is +/- power supply design. Therefore, it doesnt need DC blocking cap.
The D4 is single power supply design, it has DC blocing cap inside.
If your player has DC output, it can still work fine with the D4.
Please test the T3 with other player. If it works fine, the problem suppose to be the DC output on the J3. You should contact the manufacturer for warranty. High DC output can damage your headphone.
Pleaes check the T3 with other player first and get back to us.

 

 

how can I test DC output on J3?

 

 

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post #3 of 14
5/29/11 at 2:43am

Get hold of a cheap digital multimeter set to the mV range and a mini to mini cable. Plug one end into the J3 and then play music - then put one DMM probe on the ground part of the jack (the one closest to the body of the plug) and then put the other probe on the middle and tip parts alternately. Note what readings you get for each part; if they're over about 50mV, then we have a problem.

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post #4 of 14
5/29/11 at 3:36am
Thread Starter 

Thanks.. I have an analogue meter and used that (tested on battery first).    The I tested the J3 as you suggested

 

I had no reading using all 3 of the dcv levels (15, 150, 1000).  If memory serves me, you are supposed to use a voltage setting higher than expected output but I tried all to be safe.

 

Would analogue meter be sensitive enough?  

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post #5 of 14
5/29/11 at 3:48am

You'll almost certainly need a meter with a 2000/200mV range for DC offset. If you are getting 15V of offset then that's a pretty impressive feat from a presumably ~5v battery. I wouldn't worry about using a too-low setting - at these tiny voltages you're very unlikely to fry anything.

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post #6 of 14
5/29/11 at 3:53am
Thread Starter 

Sorry Joe, I do not know electronics...  It sounds like you are saying I need a meter with a higher number (2000) than the one I have... correct?

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post #7 of 14
5/29/11 at 4:04am
Quote:
Originally Posted by Rat Salad View Post

Sorry Joe, I do not know electronics...  It sounds like you are saying I need a meter with a higher number (2000) than the one I have... correct?

 

Not quite. Were your measurements in millivolts (mV) or volts (V)? You'll be using the former rather than the latter. 2000mV is the same as 2V, it's just that multimeter manufacturers like to be confusing. So if your meter only goes down to 15 volts, you'll need a significantly finer measurement to read DC offset, which is normally in the range of 0-20 millivolts.

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post #8 of 14
5/29/11 at 4:14am
Thread Starter 

V I believe.. Maybe this pic will help.. I used all the white number settings under dcv..  I can get a digital for 20.00 if I need.P1000307.JPG

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post #9 of 14
5/29/11 at 4:18am

Yeah, it looks like it only goes down to 15V DC. A DMM, even a cheap one, is a good thing to have around, but before that try Googling around a bit to see if anyone else is having a problem with J3 DC offset before you make an investment.

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post #10 of 14
5/29/11 at 4:23am
Thread Starter 

Thank you so much Joe.  You have been patient and helpful.

 

I will grab a DMM and re-test.   

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post #11 of 14
5/29/11 at 7:26am
Thread Starter 

So with a digital MM set to 2000m I tested:

 

The J3 Line OUT registers between 0 and 1.  

 

The T3 Line IN and nothing plugged into Line OUT registers 10   

 

The T3 Line IN with a head phone plugged into the line OUT registers -500 to -600

 

The Line IN (which is the one that plugs into the J3 out) could be causing the J3 battery meter to freak eh?


Edited by Rat Salad - 5/29/11 at 7:42am
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post #12 of 14
5/29/11 at 7:59am
Thd J3 would reboot, most probably, if ur amplifier was putting the headphone out of the J3 at some voltage (which ur measurements made sure is the case).
I'd recommend not connecting the T3 to the J3 at all. Don't even try, might just kill it. I once killed an iPod, by providing it a little voltage to the headphone out.
Tell them the J3 is fine. Or that u got the J3 replaced but the problem persists. Act like a total noob infront of them, knowing nothing. Say i don't understand what u are talking about, all i know is that i got my J3 replaced and ur T3 still messes with it. My dad says its the amp, please replace it, or atleast perform some diagnostic tests on it.
Regards
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post #13 of 14
6/1/11 at 6:49pm
Thread Starter 

Thanks to you both

 

Ibasso has been pretty good after all.  They sent out a new T3 before I even had the faulty one packed up to ship back.  Will let ya know how it goes!

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post #14 of 14
6/2/11 at 4:05pm
Thread Starter 

So iBasso sent another amp.  No issues. 

 

Thanks again.. All is well that ends well

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