If the uP is factory marked, might the mask not just be factory "zapped" to the specs of the bulk manufacturing purchase order ? It would seem the most appropriate point to program any micro, if you were splitting cents of production costs to maximise profits. NAD doesn't strike me as business who spends more time than absolutely necessary on manufacturing - at any level. 😀
Dunno is the honest answer to that Ian.
The markings on the IC I'm sure will be manufacturer markings, and there are only a few "versions" apparently 010, 016 etc. The data sheet makes no mention of these.
A lot of unknowns.
The markings on the IC I'm sure will be manufacturer markings, and there are only a few "versions" apparently 010, 016 etc. The data sheet makes no mention of these.
A lot of unknowns.
Fitting a new TC9273N-010 analogue switching I.C. to the 340 cured the fault. As I type this I'm listening to Classic FM via this amp., which sounds beautiful! The circuit diagram and PCB layout specifies the '010' version in any case.
Sorry for waking this old thread up, but I just have to thank the nice fellow who came up with the cure. Just fixed my Nad C 340 with the instructions.
I was actually told back in 2005 that this is "unfixable problem" and "costs at least 200 euro to fix, it isn't worth it". I'm glad that I waited these years and eventually found this thread by accident.
So I took out TC9273N-010 and soldered in a socket to which i installed a new IC chip in in case the chip will burn again. Total cost = 10 euro.
Thank you!
I was actually told back in 2005 that this is "unfixable problem" and "costs at least 200 euro to fix, it isn't worth it". I'm glad that I waited these years and eventually found this thread by accident.
So I took out TC9273N-010 and soldered in a socket to which i installed a new IC chip in in case the chip will burn again. Total cost = 10 euro.
Thank you!
Sorry to resurrect this old thread, but I am looking to source a TC9273N-010 myself. Any steers would be highly appreciated.
The issue is the same; right channel weak/absent, and all inputs active at the same time, despite the front selection button changing LEDs
The issue is the same; right channel weak/absent, and all inputs active at the same time, despite the front selection button changing LEDs
These are an old device now and you might be stuck with eBay or similar. There are plenty on offer.
We changed dozens of these in years past, they were used in all kinds of all in one audio systems.
We changed dozens of these in years past, they were used in all kinds of all in one audio systems.
This is a coincidence!
Just this evening I picked up (rescued) a NAD C340 with the same symptoms - on channel dead and all inputs active. eBay seems to have a lot of TC9273N-010 listed. Given that these are fairly old devices, I'm hoping the ones on eBay are not counterfeits.
Rgds
Mayank
Just this evening I picked up (rescued) a NAD C340 with the same symptoms - on channel dead and all inputs active. eBay seems to have a lot of TC9273N-010 listed. Given that these are fairly old devices, I'm hoping the ones on eBay are not counterfeits.
Rgds
Mayank
I bought mine from a chinese seller for about gbp 3, and it arrived in a week, and worked fine. Soldering it in was a pain, this whole amp is a pain to disassemble and work on.
It worked absolutely fine. But i spotted an intermittent cutting out, which seemed like a loose connection some where on a ribbon cable. In the course of diagnosing this, i seem to have shorted some thing, and now the front selection buttons dont work, the led's dont light up, and the relay doesnt click.
FML.
It worked absolutely fine. But i spotted an intermittent cutting out, which seemed like a loose connection some where on a ribbon cable. In the course of diagnosing this, i seem to have shorted some thing, and now the front selection buttons dont work, the led's dont light up, and the relay doesnt click.
FML.
Sorry to hear that.
I too bought the TC9273N-010 IC on the auction site for $7 including shipping from China. Taking cue from your post, I did not disconnect the ribbon cables, but unscrewed both the front and rear panels. With a bit of effort and careful soldering, the replaced IC has got the amplifier back in business!
The C340 sounds fairly decent, but it is a pain to service.
Hope you can get yours working again too.
Rgds
Mayank
I too bought the TC9273N-010 IC on the auction site for $7 including shipping from China. Taking cue from your post, I did not disconnect the ribbon cables, but unscrewed both the front and rear panels. With a bit of effort and careful soldering, the replaced IC has got the amplifier back in business!
The C340 sounds fairly decent, but it is a pain to service.
Hope you can get yours working again too.
Rgds
Mayank
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