Mind if i ask how you determined that? Im trying to learn as well. The main problem i am having is something in this circut is shorted which keeps causing it to go up in smoke. This specific piece on all the other outputs will output to both end legs but this one it does not. The person i am repairing this for spilt a small amount of coffee in the reciever as you can see from the small stain on it. Also found 2 bad mosfet drivers shorted to themselves.Two 0.27Ω 5W non-inductive resistors (center common).
Also is it possible to find this specific piece or does it not exist anymore?Two 0.27Ω 5W non-inductive resistors (center common).
It is a sherwood p965These are very common in receiver amp circuits and usually fail along with the output transistors. What is the make and model of the unit here? If you can, post the entire schematic (or at least the amp section).
On the schematic it is R244FL. Fl stands for front left channel. I didnt find any direct shorts but i checked ohm readings from the base to the collector and got 000 on one of them so dead transistor and the other one i pulled had different readings then all the other ones on the same board so i pulled that one off as well. All resistors are showing correct values. I have just finished pulling all burnt components off the board i can post a screenshot of where im at now. The plan right now is to replace all transistors in line and replace the burned resistors and replace the dual resistor.The part you show is a 0.27ohm dual emitter resistor as stated before. From the parts list, this is R244xx for example. Can you post here which one is failing? There should be an "R" number on the PC board. Knowing which specific one is failing will help to provide you with the likely shorted transistor that is causing this failure. If it is R2444, are both sides open? Check Q213-Q216 for shorts. Also check to see if either R229 or R230 are open.
Thank you. On this component it is testing open line across all legs. I tested the same component next to it and am getting .2 from center to each leg. So this piece is fried. Forgive me as i am still learning what is DMM. The only way i have seen to test transistors is to test resistance from base to collector or emitter. Im sure this is wrong i have all4 transistors pulled out of circut right now so i can test them. Thank you for your help.Check the resistance between the legs of that component. It is unlikely to be blown.
R takes the place of the decimal point. For example, 2R7 would be 2.7Ω.
If things are going up in smoke it is more likely one or both of the output transistors are blown shorted. Remove both transistors and test on a DMM on the diode range. Chances are you will find two legs are shorted.
Do you by chance have a link to one that delivers to america. I tried using those search terms and cant seem to find any 3 pinned versions.https://handsontec.com/index.php/product/5w-0-22rx2-non-inductive-cement-resistor/
They are sometimes described as dual emitter resistors on some sites.