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#41
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RC4558 Variants IC OP amp
"Phil Allison" in ...
"Max Hauser" wrote: ** The RC4558 was *introduced * in 1974 by Raytheon Sorry! I screwed up there, forgetting the actual RC4558 (and the focus of this thread) in the haunting maze of other and more common dual op amps of at least three distinct designs all called some kind of -558, as follows (if you're interested). It was not the RC4558 I referred to in the previous posting. More on op amps in general at the end, and a glorious historical link. Some history. The original, Motorola MC1558, was explicitly a dual 741. Its significance was partly 8-pin package, unlike earlier Fairchild and National 14-pin dual-741 types. (I also remember an early dual 741 from Raytheon, RC4136 I think, 8 pin also? -- that memory is from the early 1970s so don't hold me to precision there.) The MC1558 was supplemented by Motorola's high-speed version (MC1558S) as Jim Thompson, working there at the time, recalled recently, 22-Feb-04 in sci.electronics.design -- the second distinct circuit. These early "558" op amps were popular and became second-sourced soon by other vendors one of which, as I recall, called theirs "5558" to conform to the firm's product numbering. None of these products was the RC4558, a later design with PNP input stage. (Motorola itself then proceeded itself to second-source the RC4558 too.) In 1974 (not 1973) I put a circuit in _Popular Electronics_ calling for a "558-type" dual op amp, intending a 1558 or one of its second-sourced, slightly different-numbered versions. This yielded a file of correspondence to me in California from hobbyists as distant as Selangor, Malaysia (I just checked the file) full of requests for clarification on the "558" part number, an issue haunting me still, as you see. :-( - it is of quite *different* design to the uA741 (released in 1968) or MC1458 (a dual 741). Regarding comparisons to 741, Mr Allison employs a close-up lens, mine is a zoom. In the context of the popular Philbrick K2-W and K2-XA vacuum-tube DC-coupled op amps (still in use! _mirabile dictu_), the many successful solid-state pre-monolithic op amps including the breakthrough Philbrick P2 and P65, low-cost Nexus SQ10A, several from NV Philips; early monolithic generations of low-voltage three-stage, then high-voltage three-stage, then high-voltage two-stage designs (Fullagar's 741, Widlar's LM101), the duals we are discussing, the low-cost National "quad 741" (Fredrickson's LM324), Lovelace's NE5532, Huijsing ("Professor Op Amp")'s NE5534, the mixed-process op amps of the middle 1970s, and many others, it's possible to observe in the RC4558a bipolar design with mirror-loaded input stage, NPN Darlington second gain stage, complementary emitter-follower output stage, and internal single-pole minor-loop frequency compensation (popularized by the Philbrick K2 family, not the much later 741 as the young engineers suppose). It is possible to find designs that are indeed nearer to the original 741, but not many -- which is why some people would call it a 741-class design. (It also has the internal fixed unity-gain freq compensation decried as a limitation in Jim Roberge's classic op-amp design text -- I cited the result, a performance limitation apt to yield audible distortion.) I have some experience designing monolithic op amps (one-, two-, and three-gain-stage types, bipolar and MOS, some fast, some low-noise, some just weird) so maybe I lump more designs into the "741 class" than the next person might choose to do. If anyone would like to really learn about op amps and their ways, from a long focus, one of the Primary Sources that taught the world about op amps, the 1965 Philbrick Applications Manual, is now online, thanks in part I believe to one of its authors (Dan Sheingold). The current link is http://www.analog.com/library/analog...mplifiers.html -- be sure to re-assemble and paste into your browser, if the line gets wrapped to more than one. Again I hope this will find some use to someone, and apologize for still mixing "558" part numbers after thirty years. -- Max Hauser |
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#42
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RC4558 Variants IC OP amp
"Max Hauser" wrote in message ...
snip ...(I also remember an early dual 741 from Raytheon, RC4136 I think, 8 pin also? -- that memory is from the early 1970s so don't hold me to precision there.) I thought the 4136 was a 14 or 16 pin quad. Where's Lou Garner when you need him :-) |
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#43
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RC4558 Variants IC OP amp
"Max Hauser" wrote in message ...
snip ...(I also remember an early dual 741 from Raytheon, RC4136 I think, 8 pin also? -- that memory is from the early 1970s so don't hold me to precision there.) I thought the 4136 was a 14 or 16 pin quad. Where's Lou Garner when you need him :-) |
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#44
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RC4558 Variants IC OP amp
"Max Hauser" wrote in message ...
snip ...(I also remember an early dual 741 from Raytheon, RC4136 I think, 8 pin also? -- that memory is from the early 1970s so don't hold me to precision there.) I thought the 4136 was a 14 or 16 pin quad. Where's Lou Garner when you need him :-) |
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#45
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RC4558 Variants IC OP amp
"Max Hauser" wrote in message ...
snip ...(I also remember an early dual 741 from Raytheon, RC4136 I think, 8 pin also? -- that memory is from the early 1970s so don't hold me to precision there.) I thought the 4136 was a 14 or 16 pin quad. Where's Lou Garner when you need him :-) |
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#46
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RC4558 Variants IC OP amp
"unitron" ...(I also remember an early dual 741 from Raytheon, RC4136 I think, 8 pin also? -- that memory is from the early 1970s so don't hold me to precision there.) I thought the 4136 was a 14 or 16 pin quad. ** The RC4136 is a 14 pin quad version of the RC4558 dual op-amp. It has an unusual pin out for a quad - the outputs are not in each corner . The TL075 has the same odd pin out as the 4136. ............ Phil |
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#47
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RC4558 Variants IC OP amp
"unitron" ...(I also remember an early dual 741 from Raytheon, RC4136 I think, 8 pin also? -- that memory is from the early 1970s so don't hold me to precision there.) I thought the 4136 was a 14 or 16 pin quad. ** The RC4136 is a 14 pin quad version of the RC4558 dual op-amp. It has an unusual pin out for a quad - the outputs are not in each corner . The TL075 has the same odd pin out as the 4136. ............ Phil |
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#48
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RC4558 Variants IC OP amp
"unitron" ...(I also remember an early dual 741 from Raytheon, RC4136 I think, 8 pin also? -- that memory is from the early 1970s so don't hold me to precision there.) I thought the 4136 was a 14 or 16 pin quad. ** The RC4136 is a 14 pin quad version of the RC4558 dual op-amp. It has an unusual pin out for a quad - the outputs are not in each corner . The TL075 has the same odd pin out as the 4136. ............ Phil |
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#49
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RC4558 Variants IC OP amp
"unitron" ...(I also remember an early dual 741 from Raytheon, RC4136 I think, 8 pin also? -- that memory is from the early 1970s so don't hold me to precision there.) I thought the 4136 was a 14 or 16 pin quad. ** The RC4136 is a 14 pin quad version of the RC4558 dual op-amp. It has an unusual pin out for a quad - the outputs are not in each corner . The TL075 has the same odd pin out as the 4136. ............ Phil |
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#50
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RC4558 Variants IC OP amp
"unitron" in m...
I thought the 4136 was a 14 or 16 pin quad. Where's Lou Garner when you need him :-) Bullseye, "unitron!" (You knew, I assume, that my "558" circuit in PopTronics was in Lou Garner's department, and introduced by him.) Lou Garner was one of those influential constructive teachers of technology. The Philbrick apps literature I cited earlier was too, aimed more at professionals while Garner wrote to hobbyists -- overlapping groups, then as now. |
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#51
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RC4558 Variants IC OP amp
"unitron" in m...
I thought the 4136 was a 14 or 16 pin quad. Where's Lou Garner when you need him :-) Bullseye, "unitron!" (You knew, I assume, that my "558" circuit in PopTronics was in Lou Garner's department, and introduced by him.) Lou Garner was one of those influential constructive teachers of technology. The Philbrick apps literature I cited earlier was too, aimed more at professionals while Garner wrote to hobbyists -- overlapping groups, then as now. |
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#52
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RC4558 Variants IC OP amp
"unitron" in m...
I thought the 4136 was a 14 or 16 pin quad. Where's Lou Garner when you need him :-) Bullseye, "unitron!" (You knew, I assume, that my "558" circuit in PopTronics was in Lou Garner's department, and introduced by him.) Lou Garner was one of those influential constructive teachers of technology. The Philbrick apps literature I cited earlier was too, aimed more at professionals while Garner wrote to hobbyists -- overlapping groups, then as now. |
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#53
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RC4558 Variants IC OP amp
"unitron" in m...
I thought the 4136 was a 14 or 16 pin quad. Where's Lou Garner when you need him :-) Bullseye, "unitron!" (You knew, I assume, that my "558" circuit in PopTronics was in Lou Garner's department, and introduced by him.) Lou Garner was one of those influential constructive teachers of technology. The Philbrick apps literature I cited earlier was too, aimed more at professionals while Garner wrote to hobbyists -- overlapping groups, then as now. |
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#54
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RC4558 Variants IC OP amp
Front end op amps for a Fender guitar amp, (Stage Lead circa 1982). Which of these would be the proper replacement, looking for low noise, the lead channel has very high gain. Texas Instruments has the following part numbers. RC4558D RC4558DR RC4558P RC4558PSR RC4558PWR What would be the differences? any help appreciated, Vin Collins Not that it is going to matter much in a guitar amp. but you might try a 5532 instead. Straight drop in replacement and contrary to what somebody said about sockets, They are preferable to soldered IC's. Digikey has some very fine machined pin sockets gfor about 90 cents each. Peavey socketed every IC that they used for 25 years and I have never seen a failure due to a socket. Richard H. Kuschel "I canna change the law of physics."-----Scotty |
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#55
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RC4558 Variants IC OP amp
Front end op amps for a Fender guitar amp, (Stage Lead circa 1982). Which of these would be the proper replacement, looking for low noise, the lead channel has very high gain. Texas Instruments has the following part numbers. RC4558D RC4558DR RC4558P RC4558PSR RC4558PWR What would be the differences? any help appreciated, Vin Collins Not that it is going to matter much in a guitar amp. but you might try a 5532 instead. Straight drop in replacement and contrary to what somebody said about sockets, They are preferable to soldered IC's. Digikey has some very fine machined pin sockets gfor about 90 cents each. Peavey socketed every IC that they used for 25 years and I have never seen a failure due to a socket. Richard H. Kuschel "I canna change the law of physics."-----Scotty |
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#56
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RC4558 Variants IC OP amp
Front end op amps for a Fender guitar amp, (Stage Lead circa 1982). Which of these would be the proper replacement, looking for low noise, the lead channel has very high gain. Texas Instruments has the following part numbers. RC4558D RC4558DR RC4558P RC4558PSR RC4558PWR What would be the differences? any help appreciated, Vin Collins Not that it is going to matter much in a guitar amp. but you might try a 5532 instead. Straight drop in replacement and contrary to what somebody said about sockets, They are preferable to soldered IC's. Digikey has some very fine machined pin sockets gfor about 90 cents each. Peavey socketed every IC that they used for 25 years and I have never seen a failure due to a socket. Richard H. Kuschel "I canna change the law of physics."-----Scotty |
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#57
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RC4558 Variants IC OP amp
Front end op amps for a Fender guitar amp, (Stage Lead circa 1982). Which of these would be the proper replacement, looking for low noise, the lead channel has very high gain. Texas Instruments has the following part numbers. RC4558D RC4558DR RC4558P RC4558PSR RC4558PWR What would be the differences? any help appreciated, Vin Collins Not that it is going to matter much in a guitar amp. but you might try a 5532 instead. Straight drop in replacement and contrary to what somebody said about sockets, They are preferable to soldered IC's. Digikey has some very fine machined pin sockets gfor about 90 cents each. Peavey socketed every IC that they used for 25 years and I have never seen a failure due to a socket. Richard H. Kuschel "I canna change the law of physics."-----Scotty |
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#58
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RC4558 Variants IC OP amp
Peavey socketed every IC that they used for 25 years and I have never seen a failure due to a socket. I concur, never seen a problem with any socketed stuff in amps, but i guess it would be possible, maybe a dab of silicone under the chip just to make sure? Vin "Richard Kuschel" wrote in message ... Front end op amps for a Fender guitar amp, (Stage Lead circa 1982). Which of these would be the proper replacement, looking for low noise, the lead channel has very high gain. Texas Instruments has the following part numbers. RC4558D RC4558DR RC4558P RC4558PSR RC4558PWR What would be the differences? any help appreciated, Vin Collins Not that it is going to matter much in a guitar amp. but you might try a 5532 instead. Straight drop in replacement and contrary to what somebody said about sockets, They are preferable to soldered IC's. Digikey has some very fine machined pin sockets gfor about 90 cents each. Peavey socketed every IC that they used for 25 years and I have never seen a failure due to a socket. Richard H. Kuschel "I canna change the law of physics."-----Scotty |
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#59
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RC4558 Variants IC OP amp
Peavey socketed every IC that they used for 25 years and I have never seen a failure due to a socket. I concur, never seen a problem with any socketed stuff in amps, but i guess it would be possible, maybe a dab of silicone under the chip just to make sure? Vin "Richard Kuschel" wrote in message ... Front end op amps for a Fender guitar amp, (Stage Lead circa 1982). Which of these would be the proper replacement, looking for low noise, the lead channel has very high gain. Texas Instruments has the following part numbers. RC4558D RC4558DR RC4558P RC4558PSR RC4558PWR What would be the differences? any help appreciated, Vin Collins Not that it is going to matter much in a guitar amp. but you might try a 5532 instead. Straight drop in replacement and contrary to what somebody said about sockets, They are preferable to soldered IC's. Digikey has some very fine machined pin sockets gfor about 90 cents each. Peavey socketed every IC that they used for 25 years and I have never seen a failure due to a socket. Richard H. Kuschel "I canna change the law of physics."-----Scotty |
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#60
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RC4558 Variants IC OP amp
Peavey socketed every IC that they used for 25 years and I have never seen a failure due to a socket. I concur, never seen a problem with any socketed stuff in amps, but i guess it would be possible, maybe a dab of silicone under the chip just to make sure? Vin "Richard Kuschel" wrote in message ... Front end op amps for a Fender guitar amp, (Stage Lead circa 1982). Which of these would be the proper replacement, looking for low noise, the lead channel has very high gain. Texas Instruments has the following part numbers. RC4558D RC4558DR RC4558P RC4558PSR RC4558PWR What would be the differences? any help appreciated, Vin Collins Not that it is going to matter much in a guitar amp. but you might try a 5532 instead. Straight drop in replacement and contrary to what somebody said about sockets, They are preferable to soldered IC's. Digikey has some very fine machined pin sockets gfor about 90 cents each. Peavey socketed every IC that they used for 25 years and I have never seen a failure due to a socket. Richard H. Kuschel "I canna change the law of physics."-----Scotty |
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#61
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RC4558 Variants IC OP amp
Peavey socketed every IC that they used for 25 years and I have never seen a failure due to a socket. I concur, never seen a problem with any socketed stuff in amps, but i guess it would be possible, maybe a dab of silicone under the chip just to make sure? Vin "Richard Kuschel" wrote in message ... Front end op amps for a Fender guitar amp, (Stage Lead circa 1982). Which of these would be the proper replacement, looking for low noise, the lead channel has very high gain. Texas Instruments has the following part numbers. RC4558D RC4558DR RC4558P RC4558PSR RC4558PWR What would be the differences? any help appreciated, Vin Collins Not that it is going to matter much in a guitar amp. but you might try a 5532 instead. Straight drop in replacement and contrary to what somebody said about sockets, They are preferable to soldered IC's. Digikey has some very fine machined pin sockets gfor about 90 cents each. Peavey socketed every IC that they used for 25 years and I have never seen a failure due to a socket. Richard H. Kuschel "I canna change the law of physics."-----Scotty |
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#62
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RC4558 Variants IC OP amp
"JVC" wrote in message .. .
Front end op amps for a Fender guitar amp, (Stage Lead circa 1982). Which of these would be the proper replacement, looking for low noise, the lead channel has very high gain. Texas Instruments has the following part numbers. RC4558D RC4558DR RC4558P RC4558PSR RC4558PWR What would be the differences? any help appreciated, Vin Collins It's almost too unlikely to happen to warrant mention, but just in case, you should be aware that there is an integrated circuit used to generate timing pulses and this chip is often referred to as a "555". There's a dual version known as a "556" and a quad version, a lot more rare than the 555 and 556, called, you guessed it, a 558. Be sure you aren't getting a replacement for that chip. |
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#63
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RC4558 Variants IC OP amp
"JVC" wrote in message .. .
Front end op amps for a Fender guitar amp, (Stage Lead circa 1982). Which of these would be the proper replacement, looking for low noise, the lead channel has very high gain. Texas Instruments has the following part numbers. RC4558D RC4558DR RC4558P RC4558PSR RC4558PWR What would be the differences? any help appreciated, Vin Collins It's almost too unlikely to happen to warrant mention, but just in case, you should be aware that there is an integrated circuit used to generate timing pulses and this chip is often referred to as a "555". There's a dual version known as a "556" and a quad version, a lot more rare than the 555 and 556, called, you guessed it, a 558. Be sure you aren't getting a replacement for that chip. |
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#64
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RC4558 Variants IC OP amp
"JVC" wrote in message .. .
Front end op amps for a Fender guitar amp, (Stage Lead circa 1982). Which of these would be the proper replacement, looking for low noise, the lead channel has very high gain. Texas Instruments has the following part numbers. RC4558D RC4558DR RC4558P RC4558PSR RC4558PWR What would be the differences? any help appreciated, Vin Collins It's almost too unlikely to happen to warrant mention, but just in case, you should be aware that there is an integrated circuit used to generate timing pulses and this chip is often referred to as a "555". There's a dual version known as a "556" and a quad version, a lot more rare than the 555 and 556, called, you guessed it, a 558. Be sure you aren't getting a replacement for that chip. |
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#65
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RC4558 Variants IC OP amp
"JVC" wrote in message .. .
Front end op amps for a Fender guitar amp, (Stage Lead circa 1982). Which of these would be the proper replacement, looking for low noise, the lead channel has very high gain. Texas Instruments has the following part numbers. RC4558D RC4558DR RC4558P RC4558PSR RC4558PWR What would be the differences? any help appreciated, Vin Collins It's almost too unlikely to happen to warrant mention, but just in case, you should be aware that there is an integrated circuit used to generate timing pulses and this chip is often referred to as a "555". There's a dual version known as a "556" and a quad version, a lot more rare than the 555 and 556, called, you guessed it, a 558. Be sure you aren't getting a replacement for that chip. |
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#66
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RC4558 Variants IC OP amp
"JVC" wrote in message . ..
Peavey socketed every IC that they used for 25 years and I have never seen a failure due to a socket. I concur, never seen a problem with any socketed stuff in amps, but i guess it would be possible, maybe a dab of silicone under the chip just to make sure? ACK! Absolutely not! One of the by-products of the curing process is the release of acetic acid, which will wreak havoc on any electrical connections. Another issue is that you'll now have this glob of crap that will, in the future, prevent proper seating and may even force the chip out. Third issue, what do you do when you need to get the chip out for real? Bad idea, really bad idea. |
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#67
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RC4558 Variants IC OP amp
"JVC" wrote in message . ..
Peavey socketed every IC that they used for 25 years and I have never seen a failure due to a socket. I concur, never seen a problem with any socketed stuff in amps, but i guess it would be possible, maybe a dab of silicone under the chip just to make sure? ACK! Absolutely not! One of the by-products of the curing process is the release of acetic acid, which will wreak havoc on any electrical connections. Another issue is that you'll now have this glob of crap that will, in the future, prevent proper seating and may even force the chip out. Third issue, what do you do when you need to get the chip out for real? Bad idea, really bad idea. |
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#68
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RC4558 Variants IC OP amp
"JVC" wrote in message . ..
Peavey socketed every IC that they used for 25 years and I have never seen a failure due to a socket. I concur, never seen a problem with any socketed stuff in amps, but i guess it would be possible, maybe a dab of silicone under the chip just to make sure? ACK! Absolutely not! One of the by-products of the curing process is the release of acetic acid, which will wreak havoc on any electrical connections. Another issue is that you'll now have this glob of crap that will, in the future, prevent proper seating and may even force the chip out. Third issue, what do you do when you need to get the chip out for real? Bad idea, really bad idea. |
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#69
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RC4558 Variants IC OP amp
"JVC" wrote in message . ..
Peavey socketed every IC that they used for 25 years and I have never seen a failure due to a socket. I concur, never seen a problem with any socketed stuff in amps, but i guess it would be possible, maybe a dab of silicone under the chip just to make sure? ACK! Absolutely not! One of the by-products of the curing process is the release of acetic acid, which will wreak havoc on any electrical connections. Another issue is that you'll now have this glob of crap that will, in the future, prevent proper seating and may even force the chip out. Third issue, what do you do when you need to get the chip out for real? Bad idea, really bad idea. |
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#70
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RC4558 Variants IC OP amp
I remember the old 555, built a bunch of guitar effects back in the
seventies from Craig Anderton's book, i used the 555 to make a ring modulator ckt IIRC,, long time ago, and about the last time I worked with IC stuff!!! Vin "unitron" wrote in message om... "JVC" wrote in message .. . Front end op amps for a Fender guitar amp, (Stage Lead circa 1982). Which of these would be the proper replacement, looking for low noise, the lead channel has very high gain. Texas Instruments has the following part numbers. RC4558D RC4558DR RC4558P RC4558PSR RC4558PWR What would be the differences? any help appreciated, Vin Collins It's almost too unlikely to happen to warrant mention, but just in case, you should be aware that there is an integrated circuit used to generate timing pulses and this chip is often referred to as a "555". There's a dual version known as a "556" and a quad version, a lot more rare than the 555 and 556, called, you guessed it, a 558. Be sure you aren't getting a replacement for that chip. |
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#71
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RC4558 Variants IC OP amp
I remember the old 555, built a bunch of guitar effects back in the
seventies from Craig Anderton's book, i used the 555 to make a ring modulator ckt IIRC,, long time ago, and about the last time I worked with IC stuff!!! Vin "unitron" wrote in message om... "JVC" wrote in message .. . Front end op amps for a Fender guitar amp, (Stage Lead circa 1982). Which of these would be the proper replacement, looking for low noise, the lead channel has very high gain. Texas Instruments has the following part numbers. RC4558D RC4558DR RC4558P RC4558PSR RC4558PWR What would be the differences? any help appreciated, Vin Collins It's almost too unlikely to happen to warrant mention, but just in case, you should be aware that there is an integrated circuit used to generate timing pulses and this chip is often referred to as a "555". There's a dual version known as a "556" and a quad version, a lot more rare than the 555 and 556, called, you guessed it, a 558. Be sure you aren't getting a replacement for that chip. |
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#72
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RC4558 Variants IC OP amp
I remember the old 555, built a bunch of guitar effects back in the
seventies from Craig Anderton's book, i used the 555 to make a ring modulator ckt IIRC,, long time ago, and about the last time I worked with IC stuff!!! Vin "unitron" wrote in message om... "JVC" wrote in message .. . Front end op amps for a Fender guitar amp, (Stage Lead circa 1982). Which of these would be the proper replacement, looking for low noise, the lead channel has very high gain. Texas Instruments has the following part numbers. RC4558D RC4558DR RC4558P RC4558PSR RC4558PWR What would be the differences? any help appreciated, Vin Collins It's almost too unlikely to happen to warrant mention, but just in case, you should be aware that there is an integrated circuit used to generate timing pulses and this chip is often referred to as a "555". There's a dual version known as a "556" and a quad version, a lot more rare than the 555 and 556, called, you guessed it, a 558. Be sure you aren't getting a replacement for that chip. |
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#73
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RC4558 Variants IC OP amp
I remember the old 555, built a bunch of guitar effects back in the
seventies from Craig Anderton's book, i used the 555 to make a ring modulator ckt IIRC,, long time ago, and about the last time I worked with IC stuff!!! Vin "unitron" wrote in message om... "JVC" wrote in message .. . Front end op amps for a Fender guitar amp, (Stage Lead circa 1982). Which of these would be the proper replacement, looking for low noise, the lead channel has very high gain. Texas Instruments has the following part numbers. RC4558D RC4558DR RC4558P RC4558PSR RC4558PWR What would be the differences? any help appreciated, Vin Collins It's almost too unlikely to happen to warrant mention, but just in case, you should be aware that there is an integrated circuit used to generate timing pulses and this chip is often referred to as a "555". There's a dual version known as a "556" and a quad version, a lot more rare than the 555 and 556, called, you guessed it, a 558. Be sure you aren't getting a replacement for that chip. |
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#74
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RC4558 Variants IC OP amp
Hi Dick,
You are right, after I posted it, I started thinking about the caustic effects, remember seeing a thread about silly con over in RAT a while back,,,, this IC stuff is freaking me out!! Vin "Dick Pierce" wrote in message om... "JVC" wrote in message . .. Peavey socketed every IC that they used for 25 years and I have never seen a failure due to a socket. I concur, never seen a problem with any socketed stuff in amps, but i guess it would be possible, maybe a dab of silicone under the chip just to make sure? ACK! Absolutely not! One of the by-products of the curing process is the release of acetic acid, which will wreak havoc on any electrical connections. Another issue is that you'll now have this glob of crap that will, in the future, prevent proper seating and may even force the chip out. Third issue, what do you do when you need to get the chip out for real? Bad idea, really bad idea. |
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#75
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RC4558 Variants IC OP amp
Hi Dick,
You are right, after I posted it, I started thinking about the caustic effects, remember seeing a thread about silly con over in RAT a while back,,,, this IC stuff is freaking me out!! Vin "Dick Pierce" wrote in message om... "JVC" wrote in message . .. Peavey socketed every IC that they used for 25 years and I have never seen a failure due to a socket. I concur, never seen a problem with any socketed stuff in amps, but i guess it would be possible, maybe a dab of silicone under the chip just to make sure? ACK! Absolutely not! One of the by-products of the curing process is the release of acetic acid, which will wreak havoc on any electrical connections. Another issue is that you'll now have this glob of crap that will, in the future, prevent proper seating and may even force the chip out. Third issue, what do you do when you need to get the chip out for real? Bad idea, really bad idea. |
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#76
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RC4558 Variants IC OP amp
Hi Dick,
You are right, after I posted it, I started thinking about the caustic effects, remember seeing a thread about silly con over in RAT a while back,,,, this IC stuff is freaking me out!! Vin "Dick Pierce" wrote in message om... "JVC" wrote in message . .. Peavey socketed every IC that they used for 25 years and I have never seen a failure due to a socket. I concur, never seen a problem with any socketed stuff in amps, but i guess it would be possible, maybe a dab of silicone under the chip just to make sure? ACK! Absolutely not! One of the by-products of the curing process is the release of acetic acid, which will wreak havoc on any electrical connections. Another issue is that you'll now have this glob of crap that will, in the future, prevent proper seating and may even force the chip out. Third issue, what do you do when you need to get the chip out for real? Bad idea, really bad idea. |
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#77
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RC4558 Variants IC OP amp
Hi Dick,
You are right, after I posted it, I started thinking about the caustic effects, remember seeing a thread about silly con over in RAT a while back,,,, this IC stuff is freaking me out!! Vin "Dick Pierce" wrote in message om... "JVC" wrote in message . .. Peavey socketed every IC that they used for 25 years and I have never seen a failure due to a socket. I concur, never seen a problem with any socketed stuff in amps, but i guess it would be possible, maybe a dab of silicone under the chip just to make sure? ACK! Absolutely not! One of the by-products of the curing process is the release of acetic acid, which will wreak havoc on any electrical connections. Another issue is that you'll now have this glob of crap that will, in the future, prevent proper seating and may even force the chip out. Third issue, what do you do when you need to get the chip out for real? Bad idea, really bad idea. |
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#78
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RC4558 Variants IC OP amp
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#79
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RC4558 Variants IC OP amp
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Linear Mode
