Op-Amp Substitution

[pfjw@aol.com]

Odd Question. I am repairing a Sony mixer for a friend and it has a bad JRC 5023 op amp. It is dead-shorted - so I know it is bad. The rest of the board, diodes and transistors check OK.

As it happens, from a previous repair, I happen to have some jfet LF356 op amps in stock.

The operating voltages are within range. But the 5023 is a video/audio amp, the 356 seems to be 'more so'.
Given that there is some urgency on this and the mixer is quite obsolete (1980s vintage), waiting to get the parts from Mouser (Not in stock) or Newark, Digikey and so forth is easy enough but for the time constraint.

NOTE: I can troubleshoot discrete components and such easily enough. I boggle a bit at ICs, so thanks in advance for any suggestions.

Peter Wieck
Melrose Park, PA

 

[Phil Allison]

<pfjw@aol.com>

Odd Question. I am repairing a Sony mixer for a friend and it has a bad
JRC 5023 op amp.

** No hits on that number, but Intersil make a version - the HA5023

http://www.intersil.com/content/dam/Intersil/documents/fn33/fn3393.pdf

Mighty unusual to find one in a audio desk.

As it happens, from a previous repair, I happen to have some jfet LF356
op amps in stock.

** Probably work OK, but the common NE5532 is a lot closer.

I would put an 8 pin DIL socket in the PCB for safety.


..... Phil

 

[Phil Allison]

<pfjw@aol.com>

Odd Question. I am repairing a Sony mixer ..

** What sort of "mixer" ??

Audio or video ???




..... Phil

 

[Phil Allison]

<pfjw@aol.com>

** What sort of "mixer" ??

Audio.

** I strongly believe the op-amp IS in fact JRC5532.

JRC used to make them under licence from Signetics.

The numbers on the pack may be poorly printed or worn after 30 years.

Using an op-amp with the part number you supplied in an audio desk is non
credible.



..... Phil

 

[pfjw@aol.com]

On Saturday, February 23, 2013 7:45:53 PM UTC-5, Phil Allison wrote:

pfjw@aol.com



Odd Question. I am repairing a Sony mixer ..



** What sort of "mixer" ??



Audio or video ???









.... Phil

Audio.

 

[pfjw@aol.com]

On Saturday, February 23, 2013 7:30:12 PM UTC-5, Phil Allison wrote:

pfjw@aol.com



Odd Question. I am repairing a Sony mixer for a friend and it has a bad

JRC 5023 op amp.



** No hits on that number, but Intersil make a version - the HA5023



http://www.intersil.com/content/dam/Intersil/documents/fn33/fn3393.pdf



Mighty unusual to find one in a audio desk.





As it happens, from a previous repair, I happen to have some jfet LF356

op amps in stock.



** Probably work OK, but the common NE5532 is a lot closer.



I would put an 8 pin DIL socket in the PCB for safety.





.... Phil

That is a given.

 

[hrhofann@sbcglobal.net]

On Feb 23, 4:23 pm, "p...@aol.com" <p...@aol.com> wrote:

Odd Question. I am repairing a Sony mixer for a friend and it has a bad JRC 5023 op amp.  It is dead-shorted - so I know it is bad. The rest of the board, diodes and transistors check OK.

As it happens, from a previous repair, I happen to have some jfet LF356 op amps in stock.

The operating voltages are within range. But the 5023 is a video/audio amp, the 356 seems to be 'more so'.
Given that there is some urgency on this and the mixer is quite obsolete (1980s vintage), waiting to get the parts from Mouser (Not in stock) or Newark, Digikey and so forth is easy enough but for the time constraint.

NOTE: I can troubleshoot discrete components and such easily enough. I boggle a bit at ICs, so thanks in advance for any suggestions.

Peter Wieck
Melrose Park, PA

I didn't know SONY made kitchen appliances<g>.

 

[pfjw@aol.com]

On Saturday, February 23, 2013 8:52:36 PM UTC-5, Phil Allison wrote:

pfjw@aol.com



** What sort of "mixer" ??



Audio.







** I strongly believe the op-amp IS in fact JRC5532.



JRC used to make them under licence from Signetics.



The numbers on the pack may be poorly printed or worn after 30 years.



Using an op-amp with the part number you supplied in an audio desk is non

credible.

Phil:

5023 is the correct part number. It is listed as such on the schematic, and there are several of them in the unit. Non-credible or otherwise, that is the one. The original question remains - is the Jfet substitition feasible?

Peter Wieck
Melrose Park, PA

 

[whit3rd]

On Saturday, February 23, 2013 2:23:08 PM UTC-8, pf...@aol.com wrote:

Odd Question. I am repairing a Sony mixer for a friend and it has a bad JRC 5023 op amp. It is dead-shorted - so I know it is bad. The rest of the board, diodes and transistors check OK.

Well, if it's really a single-unit op amp (eight pins, with output on pin #6), there's lots
of substitutions, including LM356, that might work.

JRC (Japan Radio Corp) usually uses NJMnnnn part numbers, and their
low-noise audio single op amp that's most likely is NJM5534 (which has already
been suggested). If there's a JRC5023 marking, it's possibly a house-numbered
part (in mass production, it's common to deliver chips with markings specific
to a customer).

 

[Phil Allison]

<pfjw@aol.com>

In any case, I will purchase a couple of sockets and drop in the jfet
units that I have and report back.

** FFS purchase a couple of NE5532s as well.

These are low noise, low impedance devices and the LF356 is not.


For the record, during my research into this a little bit, the JRC5023 was
pretty much reviled by those who favor this mixer - and although the same
4-digit part number was often suggested, it was always by a different maker.


** Horse poo.

Thank you all for your replies - I was not trying to raise any controversy,
just ask a simple question.

** That was no simple question - piss head.

The 5023 op-amp is an RF type that has no place being used in an audio
mixer.

So far, I have gotten a 'might' and a 'possible'.

** Really?

How surprising !!!

You supplied us NO info on what purpose the op-amp was being used for or
even what Sony desk it was.

I see age has not made you any wiser, Peter.

You are still the same shit head you always were.


.... Phil

 

[Michael A. Terrell]

"pfjw@aol.com" wrote:


Long time since I've seen a post from you, Peter.

Odd Question. I am repairing a Sony mixer for a friend and it has a bad JRC 5023 op amp. It is dead-shorted - so I know it is bad. The rest of the board, diodes and transistors check OK.

As it happens, from a previous repair, I happen to have some jfet LF356 op amps in stock.

The operating voltages are within range. But the 5023 is a video/audio amp, the 356 seems to be 'more so'.
Given that there is some urgency on this and the mixer is quite obsolete (1980s vintage), waiting to get the parts from Mouser (Not in stock) or Newark, Digikey and so forth is easy enough but for the time constraint.

NOTE: I can troubleshoot discrete components and such easily enough. I boggle a bit at ICs, so thanks in advance for any suggestions.

Why would they use a video amp for audio? You are referencing a
RCA/Intersil/Harris/Intersil number which has nothing to do with a JRC
numbered part.

Does the schematic match the pinout of the FET Opamp? How is it
used? As an amp, or part of a filter? It should work in most circuits,
as long as the original part isn't a current amp.


Opamps are just blocks of gain. Their gain is set with resistors, so
the exact Opamp isn't critcal. The supply voltage, noise figure & DC
offset are. A 30 year old Opamp doesn't have much to brag about when it
comes to noise figure or offset. The only other problem is driving a
high capacitance load which can make it unstable.



I have used the LF373 dual version to replace older dual bipolar
Opamps with no real problems.

 

[pfjw@aol.com]

On Sunday, February 24, 2013 7:09:52 PM UTC-5, whit3rd wrote:

On Saturday, February 23, 2013 2:23:08 PM UTC-8, pf...@aol.com wrote:

Odd Question. I am repairing a Sony mixer for a friend and it has a bad JRC 5023 op amp. It is dead-shorted - so I know it is bad. The rest of the board, diodes and transistors check OK.



Well, if it's really a single-unit op amp (eight pins, with output on pin #6), there's lots

of substitutions, including LM356, that might work.



JRC (Japan Radio Corp) usually uses NJMnnnn part numbers, and their

low-noise audio single op amp that's most likely is NJM5534 (which has already

been suggested). If there's a JRC5023 marking, it's possibly a house-numbered

part (in mass production, it's common to deliver chips with markings specific

to a customer).

All of which makes perfect sense - except that there is a 5023 part number made by various makers that is listed as a direct substitution.

In any case, I will purchase a couple of sockets and drop in the jfet units that I have and report back. For the record, during my research into this a little bit, the JRC5023 was pretty much reviled by those who favor this mixer - and although the same 4-digit part number was often suggested, it was always by a different maker.

Thank you all for your replies - I was not trying to raise any controversy, just ask a simple question. So far, I have gotten a 'might' and a 'possible'. Good enough to see if it will suit the need for the moment. Meanwhile, I will order the correct parts should the 356 fail in practice.

Peter Wieck
Melrose Park, PA

 

What is the model number of the mixer? I should be able to get the actual Sony part number and provide a sub.

Dan