LA6458SS replacement?

[bamavette]

I am working on an NAD cassette deck I picked up at a thrift store with a bad LA6458SS opamp (9 pin LIP). The only options I have found are Ebay or NTE1529. The NTE appears to be a drop in replacement but I am a bit leery, and ebay is always a gamble.

Should I go with the NTE, ebay, or something else?

Thanks

 

[JonSnell Electronic]

I would put a DIL version (4558 or similar dual opamp) on a piece of veroboard and wire it in.
Pin for pin, they are the same.
OR
straighten pins 1 - 4 out and insert them in the pcb running short solid wires to the other pins 5 - 8.

 

[bamavette]

I have some JRC4558 in my stash. As I see it I would just use pins 2 thru 9 on the board with pins 1 thru 8 on the 4558.

 

[JonSnell Electronic]

Nine pins?
Use pin 1 of the 4558 as pin 2 of the LA6458S

 

[bamavette]

JonSnell that was what I was thinking. Pin 1 on the chip to pin 2 on the board and so on. I have some perf board and will make an inline adapter. Thanks for the idea.

 

[bamavette]

Should I put a 100nf capacitor across the rails on the newer 4558?

 

[bamavette]

Got it fixed. The problem was I couldn't get the output level to service manual specs. Suppose to be 505mv with a calibration tape, I was getting 150mv. Changing the chip (trim circuit) brought it up to 250mv. I started checking capacitors in the circuit and a 1000uf was 900uf but had an esr of 150 ohms. Replacing that brought it up the rest of the way.

 

[Boydk]

So.....
Your LA6458 was probably alright all the time 😉