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739 AND 5558 IC CROSSREFERENCE

Started by EDWARDEFFECT1, March 31, 2010, 07:26:02 PM

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EDWARDEFFECT1

DOES ANYONE KNOW WHAT IC CHIPS WILL REPLACE A 739 14 PIN IC AND A 5558 8 PIN IC? I HAVE A NEC 7411 CHIP IN PLACE OF THE 739 CHIP AND I GET SIGNAL IN BUT NOTHING COMING OUT..THANKS...ED!!

J M Fahey

1) Please don't SCREAM.
Writing in ALL CAPS means SCREAMING.
2) Those are pretty obsolete types.
What are you trying to build?
The "739" is the excellent, old, and unobtainable RC4739, which has no substitute that I know of.
In fact its pinout is incompatible with any other, so you can not replace it with something cheaper.
"7411" sounds like a date code to me; I found no chip with that number.
3) The "5558" is a second-source 1458, cheap and easy to get.
A 4558 will sound better and hiss less.

Enzo

A 7411 could be an old TTL logic IC, a triple three input nand.  Can't imagine it would belong there or function, only common quality being the 14 pin DIP.  So I suspect you are correct that it is a date code.

The uA739 doesn;t lend itself to any drop in replacements, but other than pinout, is there anything special about it?  Any reason we can;t take a modern op amp and mount it with a few jumper wires?  it has those compensation pins we never see anymore, but if we ignored those and wired in a 4558, would we be missing anything?  Or are they more than compensation pins, and they set gain or bandwidth or something?

The RC4739 doesn't have those compensation pins, does it?

other than as historical notes, I have not worked with either of them much, at least not in the last 20 years.

J M Fahey

Hi Enzo, I agree with you, that's why I asked Edward to post what he was trying to build.
I guess it's one of Anderton's projects for musicians.
Good and simple designs, although somewhat dated, problem is he designed with Op Amps that even then were somewhat difficult to find, he warns about that on the book (which I bought in London in 1986, it was "modern" way back then). Oh well.
The obvious solution is to slightly redesign the boards, no big deal.
*IF* Edward is repairing some old effect, he should follow your advice, let the IC "float" over the board, held by short wires going to the correct holes.
A drop or two of hot glue will help to avoid vibration problems.
And yes, a 4558 will be much closer to the original ones than a TL072.

EDWARDEFFECT1

these chips are in a kustom L1 amp.i have jrc4558 chips ,but seem to have a problem getting the right chip for a 739 ic.i get signal to the chip ,but nothing is coming thru it.....any help appreciated.i bought a new chip for it. mouser gave me a nec 7411 chip to replace it. i don't think it is working right....thanks...ed!   again sory for the caps....ed!

J M Fahey

Hi edward. The chip Mouser gave you isuseless and may/will damage your amp. Are you sure the original one is bad ? ... or you replaced it "just in case"? .... replace it and chech DC voltages in all its pins, maybe the problem was somewhere else.
As Enzo always says, post here the board number, it's something like PC5067 , PC1011 or similar code.
Just as an example, an old Kustom schematic chock full of unobtainable 739, 5558 and other delights.
Check it, it might somewhat match yours.

The 5558 look pin compatible with easy to get RC1458 ; the 80848 look like an early version of CA3080, being pin compatible with LM741 but having an extra pin 5 gain control; the 739 will have to be replaced, as Enzo said, with a "dead bug " mounted RC4558 or similar, with thin wire joining compatible pins and God help you with 40841 dual gate Mos Fets, if you happen to need them.

amp_tramp

You can use an NTE949 to replace the 739 in SOME circuits.  The 739 has pins for lag networks that are important for stability in some designs that the 949 does not have, you may need to restabilize the amp elsewhere if this is the case.

You (usually) need to add a 5000 ohm resistor from the output pins (one each from pins1 and 7) of the 949 to the V- pin (pin 4).  You may be able to skip this in circuits where there is already a resistor there.

amp_tramp

Try using the RC4560 or even the RC4580 to replace the 1458/4558.  MUCH nicer.

TJEsmooth61

Ok.. just joind your forum to answer this question
Ua739 has a few replacement :-
Ua749 .. does not have same audio db filter but will work
MC1303L direct equivalent
RC4739 direct equivalent

you can also make / use an RC4558 with small surface mount chip adaptor to suit 14pin dip