Resistor Array ID

[mike123333]

Hello - I am working on a professional keyboard Korg PA800 this is the CPU board and I need a better understanding as to identifying the resistor array. the resistor array is the RA123 or 126, the resistance I am getting across the pins is 2.841,6.63,6.61,6.64,3.220 when I switch the leads around I get the reading at the same points of 3.231,6.63,6.61,6.64,2.826. My questions is two fold, first is the resistance out of tolerance , and it could be worse under load, and what would this resistor be called if I need to order another one? I know the marking 332 is a 3.3 Kohm but it is doubling after the first resistor.

I do have several of these resistors on the board, some read good ( around 3.3k Ohms) both way and others have similar reading to what I posted above.

The issue I am having is RAM memory causing sound distortion. Any help would be greatly appreciated. I do have the SM on the unit but it does not give out any details.

[R_J]

Re: Resistor Array ID

The service manual has your answer. Pins 5 and 10 are common to one end of the array, pins 1,2,3,4,6,7,8,9 are the other end of the resistor
If you mesasure from either pin 5 or 10 to any other pin you should get 3.3k. if you measure from (ie) 1 to 2 you will measure 2 resistors in series, 6.6k.

[mike123333]

Re: Resistor Array ID

Thanks for the reply that makes sense. I did notice that while reviewing the manual but did not fully understand. I did re-measure and everything seems to be within 5% of 3.3 kohms. However when I swap the leads and measure I measure down to 2.8 kohms give or take. Would this mean that the resistor pack is faulty? I am seeing this on most all of this type of array, my hunch is that since they are reading about the same it is not an issue.

[R_J]

Re: Resistor Array ID

You are reading something else in the circuit (ie input or output of an ic etc.) The chances of those going bad is not very likely.