741 op amp variations

Good morning,

I am trying to fix a tape tensioning problem on an MCI JH 16 analog torque board.

There are 26 socketed 741 op amps of roughly 10 different model numbers. Is there any difference between models numbers 741C, CN, CP, or CP1?

Mouser has a good deal on some Texas Instruments UA741CD at 19 cents each.

Is it most likely that MCI would have used all the same model number when the machine was first made in the 70s? If so, that would tell me a lot of these have been changed over the years.

Thank you,
William

Didja clean those sockets, or at least re-seat everything? The first step is a good cleaning of all edge connections and sockets. The Mouser is a fine replacement. Just make absolutely sure they are not SMD. I got some 4558's by accident that are smaller than some crabs I've had!
Mike

[quote author="sodderboy"]I got some 4558's by accident that are smaller than some crabs I've had![/quote]
...is that "Had" meaning "Eaten" or "had" meaning "housed"???

:shock:

Keef

Umm,
housed although only temporarily, guv'nor!

Ah.

Provided temporary accomodation for, sorta fing.

I get it.

a kind of "crab Mariott", as it were...! :green:

Keef

PS: "Crab Marriott"... -sounds like a seafood salad, or perhaps a 'Humble Pie' B-side...

[quote author="Mailliw"]Good morning,

I am trying to fix a tape tensioning problem on an MCI JH 16 analog torque board.

There are 26 socketed 741 op amps of roughly 10 different model numbers. Is there any difference between models numbers 741C, CN, CP, or CP1?

Mouser has a good deal on some Texas Instruments UA741CD at 19 cents each.

Is it most likely that MCI would have used all the same model number when the machine was first made in the 70s? If so, that would tell me a lot of these have been changed over the years.

Thank you,
William[/quote]

The C version indicates it was made in Canada. Not sure where. The CN indicates it was made in Canada at Night. The CD version (the deal from Mouser) was made Canada during the Day. Not sure about the CP and CP1. Maybe not a Canadian part at all.

I remember when the 741 was introduced... all the versions were confusing. 741PE, 741BC, 741MB, etc. The 741YT is rare and probally the best sounding of the series. Can't say which is best for tape tensioning.

Vince Poulos
Speck Electronics
4-1-07

[quote author="Vince@Speck"]The C version indicates it was made in Canada. Not sure where. The CN indicates it was made in Canada at Night. The CD version (the deal from Mouser) was made Canada during the Day. Not sure about the CP and CP1. Maybe not a Canadian part at all...

4-1-07[/quote]

CP means it was made by a small company staffed by members of the Communist Party, and was intended for the Eastern Bloc, a market just opening up with detente. CP1 is the higher-spec selected version, because although all 741s are equal, some are more equal than others.

Peace,
Paul

Eight legs goooood, fourteen legs baaaad!

The 741YT is rare and probally the best sounding of the series.

Click to expand...

I think I've heard that the 741CH was even better. As it was hand-made in Switzerland it was more on the pricy side though.

Samuel

[quote author="AnalogPackrat"]fourteen legs baaaad![/quote]

especially 4 741.

Keef

Thanks

[quote author="SSLtech"][quote author="AnalogPackrat"]fourteen legs baaaad![/quote]

especially 4 741.
[/quote]

Actually NS made the 741 available in lots of packages (TO-8, 10 pin flatpack, etc.). One option was a 14-pin cerdip--LM741J-14 and LM741AJ-14, believe it or not.

A P

yeah, I have some TO-8's here. The Harrison channels have 4741s in them also... and they actually sound pretty cool.

Keith

I still use 5548'th in the console, they contain pair of 741'th per case. They sound great when output stage is rebiased in class A using 7.5K resistor.