Wow thanks a lot for the schematic.
Regarding the driver IC, do you have any idea where to find it? I've always thought that IC is some kind of OEM part made exclusively for Elac.
Duong
Elac offered to send me a number then. They are made for them as you state. I can try to ask for a few if you like.
Probably needless to say but giving the 7815/7915 combo a separate small 2 x 15V transformer is a good solution to get rid of the heat dissipating resistors R108, R112 and R113.
Hi, interesting thread!
I picked up a pair of AM150 recently and one of the amplifiers is broken. Specifically the "woofer" amp. The tweeter still works fine. I figured out already that the woofer amp outputs a ~90 kHz clipped sine wave at ~+-20 V! The snubber resistors R212 is burnt - makes sense given the "high frequency" power it has to dissipate with this defect.
The discrete transistors seem to be fine and I suspect the TDA180 to be the issues here, as I can measure the oscillations at the output pin 8 of this IC.
Sounds interesting. No idea what's inside this TDA180. Could be some sort of differential input stage? Do you have any information about this chip or if it's possible to get them from ELAC?
If not, I already though about replacing the woofer amp by a generic ~50 W amp module.
Cheers
I picked up a pair of AM150 recently and one of the amplifiers is broken. Specifically the "woofer" amp. The tweeter still works fine. I figured out already that the woofer amp outputs a ~90 kHz clipped sine wave at ~+-20 V! The snubber resistors R212 is burnt - makes sense given the "high frequency" power it has to dissipate with this defect.
The discrete transistors seem to be fine and I suspect the TDA180 to be the issues here, as I can measure the oscillations at the output pin 8 of this IC.
Sounds interesting. No idea what's inside this TDA180. Could be some sort of differential input stage? Do you have any information about this chip or if it's possible to get them from ELAC?
If not, I already though about replacing the woofer amp by a generic ~50 W amp module.
Cheers
Replacement TDA180
I am trying to repair an AM-150 and have a faulty driver chip to replace.
Thanks in advance.
Were you successful in obtaining of finding a source for the TDA180 or obtaining them from ELAC?
I am trying to repair an AM-150 and have a faulty driver chip to replace.
Thanks in advance.
You could try removing the 500r resistor and see what effect it has.
Some amps will pop/thump the speaker on power up/down if one rail goes before the other and the 500r probably stops that.
As for bad capacitors that is usually down to old age.
Electrolytics tend to age first.
Some amps will pop/thump the speaker on power up/down if one rail goes before the other and the 500r probably stops that.
As for bad capacitors that is usually down to old age.
Electrolytics tend to age first.
Elac AM-150 TDA 180
Any luck with TDA 180 component from Elac?
Did you get parts or do you have any information of what it is/do?
Any luck with TDA 180 component from Elac?
Did you get parts or do you have any information of what it is/do?
Hi, regarding AM180, crackling sound often comes from certain components that are glued with cheap contact glue that corrodes on the circuit board copper paths and corrodes connections between both sides of the pcb on glued surfaces, all glue must be removed, use cooling spray when you remove the glue, it is less risk of damaging the pcb then. The next step is to repair the connections between the pcb on both sides. If you are lucky, the drive circuit IC is in operation, but you have to clean the pins from the bad glue, use a soldering station that can melt the solder in a short time and use a solder sucker from Japanese Engineer that minimizes damage to the pcb. Good luck.