Craig Anderton projects & RC4739/XR4739 op-amp....is NTE947D a direct sub?

[davesisk]

Hi folks:

I've got Craig Anderton's "Electronic Projects for Musician's" book, and I'm discovering that the op-amp he seemed to love to use is obsolete and apparently no longer available...the 4739.  In searching on Mouser.com, the NTE947D comes up as a cross-reference.  Here's the page:

http://www.mouser.com/search/ProductDetail.aspx?R=NTE947Dvirtualkey52600000virtualkey526-NTE947D

Looks like it's in stock there...does anyone know for sure if this is a direct replacement for the 4739 that Craig seemed to love?  Or, will it work fine but the pin mappings are different and have to be remapped to his circuits?

Thanks!
Dave

[oskar]

Look around for Craigs project on the net. There are substitutes but they are all other pinouts.
I think PAIA (who sold the kits and perhaps still do) use NE5532 instead.

[CGDARK]

No, it is not a direct replacement. The direct replacement was the NTE725, but it has been discontinued. I think you still can find it.

CG

[John Lyons]

Take a look at General Guitar Gadgets as a number of the Craig Anderton layouts have been reworked there to use a 5532.
It's under "other projects" I belieive.

John

[R.G.]

Or you could go read GEO - http://www.geofex.com - for how to replace those simply and easily with whatever parts you can get.

"Replacing the Anderton 4739 and CLM6000"http://geofex.com/FX_images/anderton.gif

"Effects prototyping techniques" http://geofex.com/Article_Folders/protostyles/proto_styles.htm

[Mark Hammer]

The 4739, whether Exar or National or Raytheon, was a pretty good dual op-amp for its time, back when most of the people here were iddy-biddy babies.  Op-amps have moved on, gotten cheaper, and we should take advantage of that.  I think Craig would be the first one to agree.  JD Sleep has reworked most of the pertinent PCB layouts from EPFM to use 8-pin dual op-amps instead of 14-pin 4739s and posted them on his GGG site.  Take advantage of that.

[dr]

....I may be wrong, but I remember substituting an LF347 for the 4739 and finding out it worked-I just can't remember which pedal it was that I built...or why...

[Mark Hammer]

I'm sure you could have subbed it on a perfed or veroed project, but the 347 has the same pinout as a 324/TL074/etc and would not be pin-for-pin compatible with a 4739.

[alex frias]

I redesigned 2 PCB`s in order of using an easy-to-find dual 8 pin op amp CI (TL072, 4558, etc.).
Well it was 15 years ago and my phaser and my ring modulator are working OK.
Even that time the C.A. CI's was a bit exotic for me...

Then one year ago I discovered those same layouts in GGG.
Great job...

[PianoJane]

I just bought both the 4739 (and two 4136) from a company in Milwaukee Wisconsin called aceffects.com

They are selling hybrid replacements made in house. I dropped it in my old Polytone and had her up and running again, and it sounded great. A unique place to say the least but they have the stuff up to the ceiling!

Anyone selling any old ACEffects pedals please write!

[PianoJane]

Sorry:    jane.marek@yahoo.com

I am especialy looking for an aceffects's Illegal Buzz, Sound Trip or Ace Wah. Preferrably with original box.

(Pre 1990 Illegal Buzz)

I am also looking to buy a HD chip for the Illegal Buzz years 1991 thru 2000,  $$

Thanks!

[Mark Hammer]

The LM/XR4739 has a pin-fpr-pin equivalent in the LM1303.  Both were intended as chips for things like phone preamps.

http://www.diystompboxes.com/smfforum/index.php?topic=79142.0

[PianoJane]

I was not able to find the LM1303 anywhere, I contacted National Semiconductor's office in Santa Clara and they told me that it has not been made in years.

I bought two NTE947s off ebay but neither worked, I am not sure if it is because it has external compensation pins where the XR4739 does not? Another circuit I have that has an op amp with compensation pins not connected works fine, so I don;t think that is why.

I wish I could just remake the wiring board but I don't want to modify it. The drop in ones from acefffects worked. Nothing else seems to work. I saw that Moser has NTE947s but they are not cheap and I'd hate to not have then work like the ones off ebay. 

[12Bass]

I may have a few RC4739 and RC4136 chips around from my old EPFM days.  If I were building now, I'd use something better. 

[Mark Hammer]

I still have 8 or so Fairchild ua4739s, that I mistakenly bought way way back.  These are the uncompensated variety, so one needs to stick a compensation cap in the loop somewhere between pins 2-4 and 10-12.