Another AVT150 TDA7293 problem - please help

[niak]

hey,

i scored an AVT150 valvestate2000 that doesnt work. i have opened her up and found blown fuse. on closer inspection i have found shattered TDA7293 chips. i have searched and found too many people with this same problem.

i replaced the fuse, disconnected the output modules and it turns on with sound coming out the headphone and emulated line output.

i have some TDA7293 chips on order, but am in no way confident in my skills and would like to get some replacement modules.

the only place i have found these online is http://www.catalinaguitars.com/catal...roducts_id=797

these seem to have 2 more caps on the end of the modules, are they they same thing ?

i live in Australia and need some advice on the best place to get some of these.

could there be more damage to the mainboard ? i have read alot of people talking about a broken mute circut but cant find any threads dedicated to this problem.

[xrox]

Hi, I too am working on the same amp. Bought it used for cheap under the impression that it only needed the two chips replaced. I received it only to noticed one of the boards was missing all together. I found them for $55 each shipped from the UK. After installing I turned on the amp and poof they both fried. I discovered that I was missing the PSU-VE of negative 48 volts. They relied on the capacitor c141's lead to connect the top trace to the bottom. So the lead had a cold solder joint under the cap. Not saying it's your problem because I still haven't turned mine on after replairing the PSU-VE yet. I want to check my other voltages on the plugs going to the chip pcbs first using a variac or most likely the bulb method. I found the tda7293's cheapest at Newark.com if you want to try replacing just the chips. Cut the leads off the old chips first and have a good solder sucker. These boards are pretty tough if you don't over heat them you can replace the chips several times. I also had a fan not spinning very fast also which may have been the original problem. I'll report back if/when I am successfull. Here's where I ordered my module from - A very helpful guy
http://o2have.co.uk/index.php

[niak]

thanks xrox.

ive emailed spares@elfa.com.au hopfully they can supply them at a resonable price.

if they are expensive i will use your contact. i hope i dont have any more problems with the amp. i just dont have the skills to anything more than parts swapping.

if it blows the chips i will take it to a specialist for repair.