Electronics experts - what is this?

SexyGreyFox · 27 Mar 2010 at 19:47

Anybody know what what the broken component is and if I can replace it with something else?

Thanks

Tonyator · 27 Mar 2010 at 19:51

That is a circuit board...

Sorry I can't be off any real help...

iamdjdz · 27 Mar 2010 at 19:53

Looks to me like a boxed wirewound resistor. Could be wrong though.

Jokester · 27 Mar 2010 at 19:54

Yeah I would guess it's a 33Ohm 5W resistor.

Gerard · 27 Mar 2010 at 19:55

A "doohicky".

Feek · 27 Mar 2010 at 20:03

Jokester said:
Yeah I would guess it's a 33Ohm 5W resistor.

That's what I'd say.

Looks like a power amp board?

Dr.EM · 27 Mar 2010 at 20:04

Jokester said:
Yeah I would guess it's a 33Ohm 5W resistor.

I concur

bodybag · 27 Mar 2010 at 21:48

Hi

The bit I have marked in red, looks to have blown, from the pic I cant tell if its a resistor or a diode.

looks like a resistor to me though.... I could be wrong

Phemo · 27 Mar 2010 at 21:49

It might just be my eyes, the picture or maybe something else but do I see a few small burn spots on the PCB in between the metal heatsink plates on the mosfets?

Burnsy2023 · 27 Mar 2010 at 21:52

bodybag said:
looks like a resistor to me though.... I could be wrong

It seems to be labeled R73 so I'm sure your right. Not sure what value from that pic though.

RobH · 27 Mar 2010 at 21:55

Regarding the first pic:

It's definitely a 5 Watt ceramic wirewound resistor. The 33J suffix isn't it's value though so you need to look for additional markings or measure the working one.

Nick1881 · 27 Mar 2010 at 21:57

RobH said:
Regarding the first pic:

It's definitely a 5 Watt ceramic wirewound resistor. The 33J suffix isn't it's value though so you need to look for additional markings or measure the working one.

It is the value, R33J as in 33 Ohms.

RobH · 27 Mar 2010 at 22:02

Nick1881 said:
It is the value, R33J as in 33 Ohms.

Are you sure?

I have some here that are marked as "7W 33J10R" and "7W 35J10R" where the 33J/35J indicates the voltage and other specs according to the datasheet.

Dr.EM · 27 Mar 2010 at 22:38

You know, now you mention it, the usual application for a pair of resistors on the output of a power amplifier will call for a value much more like 0.33ohms.

If they are on the tails of the output drivers, observe R13 and R14 on this faily standard BJT amplifier design http://sound.westhost.com/project3a.htm and the accosiated note 'R13, R14 must be 5W wirewound'.

Measure the other to be certain, it'll measure as a virtual short.

33ohm would be absurd in this instance since it must drive 8 or less ohm loads!

Feek · 27 Mar 2010 at 22:45

Simple solution is to lift one end of the other one and put a meter on it.

Burnsy2023 · 27 Mar 2010 at 22:52

Feek said:
Simple solution is to lift one end of the other one and put a meter on it.

Indeed, I'd do that regardless if I knew the value or not. It only takes a second.

Jokester · 27 Mar 2010 at 23:17

Yeah looking a bit further into it seems R33 = 0.33Ohms, 33R = 33Ohms.

Mik3 · 28 Mar 2010 at 00:01

Nick1881 said:
It is the value, R33J as in 33 Ohms.

R33 means its the 33rd resistor on the circuit. as would C33 would be the 33rd capacitor, or IC33 would be the 33rd chip

Edit: My Bad I misread the post, it says R33J on the resistor, that's 33R +/- 5%

BigglesPiP · 28 Mar 2010 at 00:47

Jokester said:
R33 = 0.33Ohms, 33R = 33Ohms.

This.

The picture is broken, one look and I reckon I can say for sure if it's the value or the ID.

Edit:

Image is back, can you get us a photo showing a more clearly what the label is for the component on the board. It may be in inductor.

SexyGreyFox · 28 Mar 2010 at 02:18

I'll get some better/closer pics tomorrow.