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Replacement for LM 2905 pin-to-pin

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ramakap

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LM2905 precision timer has gone out of production. I need to have a pin-to-pin replacement (preferably). Any other alternative is welcome.
 
Oh yea here is the Datasheet.
 

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Give us a copy of the schematic and we may be able to convert it to a 555 diagram
 
Shame, it looked like a handy IC, better than the 555 in some respects. I wonder why preduction ceased.
 
For the same reason Cassette tapes took over 8 tracks
8 track was better sound but, Cassette was more popular.
Do we need to mention VHS vs Beta?
 
hotwaterwizard said:
For the same reason Cassette tapes took over 8 tracks

There were many reasons, but mostly:

1) 8 Track sounded crap!, better frequency response (due to running at twice the speed) but lousy wow and flutter.

2) Size - 8 Tracks were MUCH larger than casettes.

3) Reliability - 8 Tracks were very unreliable, and used to chew to pieces often.

4) Recording - people recorded their own cassettes, 8 Track recorders were extremely rare, as were blank tapes - plus you had the gap where they switched tracks.

There have been MANY different cassette formats, most very short lived (including the far higher quality Elcassette from Sony) - but the Philips Compact Cassette beat them all off!.
 
Remember the old Pioneer Laser Disc the size of a record album?
They were the predecessor to CD's
 
hotwaterwizard said:
Remember the old Pioneer Laser Disc the size of a record album?
They were the predecessor to CD's

Except it was Philips Laser Disc, not Pioneer. Hitachi also did a disc called CED (Capacitive Electronic Disc), and one of the other Jananese did one as well, was it JVC?.
 
Nigel, it looks like you must argue everything.

Lets just end it here and now.

You win!

You are smarter that I am!
 
hotwaterwizard said:
Nigel, it looks like you must argue everything.

Not arguing, just correcting false information (which helps no one), Philips created laser disk, and after it's failure used the same technology to create CD - with help from Sony, mostly on error correction.

Pioneer may have licenced Laser disk from Philips?, but Philips were the creators of it.

From Wikipedia:

Laserdisc technology, using a transparent disc, was invented by David Paul Gregg in 1958 (and patented in 1961 and 1969). By 1969 Philips had developed a videodisc in reflective mode, which has great advantages over the transparent mode. MCA and Philips decided to join their efforts. They first publicly demonstrated the videodisc in 1972. LD was first available on the market, in Atlanta, on December 15, 1978, two years after the VHS VCR and five years before the CD, which is based on laserdisc technology. Philips produced the players and MCA the discs. The Philips/MCA cooperation was not successful, and discontinued after a few years. Several of the scientists responsible for the early research (Richard Wilkinson, Ray Deakin, and John Winslow) founded Optical Disc Corporation (now ODC Nimbus), and that company is still the world leader in optical disc mastering technology.
 
Remember digital audio cassete?

Remember mini disc?
 
From the same site Pioneer was the first in the commercial market to sell the players!

The laserdisc (LD) was the first commercial optical disc storage medium, and was used primarily for the presentation of movies.

During its development, the format was referred to as the "Reflective Optical Videodisc System" before MCA, who owned the patent on the technology, renamed the format Disco-Vision in 1969. By the time the format was brought to market in 1978, the hyphen had been removed from the format name, and DiscoVision became the official name. Sales of DiscoVision players & discs began on December 15, 1978 starting in Atlanta, Georgia. MCA owned the rights to the largest catalog of films in the world during this time, and they directly manufactured and distributed the discs of their movies under the "MCA DiscoVision" label. Pioneer Electronics, who entered the market in 1978 at almost exactly the time DiscoVision titles were going on sale, began manufacturing
 
I wonder how much information one of thos dics could hold since they can't have used compression as computers weren't powerful enough back then.
 
Hero999 said:
I wonder how much information one of thos dics could hold since they can't have used compression as computers weren't powerful enough back then.

No, they weren't compressed at all, which is why they were so large - not forgetting of course that LP's were a similar size, and the leading edge of home audio at the time.
 
I wonder what resolution they used. I can't have seen them using full PAL resolution since a 90 miniute film with CD quality sound will take 65.65GB of storage space!
 
Hero999 said:
I wonder what resolution they used. I can't have seen them using full PAL resolution since a 90 miniute film with CD quality sound will take 65.65GB of storage space!

Never had anything to do with it, basiclaly it floped big time!.

But a quick google soon finds that the discs were analogue, and NOT digital, with each frame of video taking a single track around the disc, and the disk spining at a constant 1500 rpm, as opposed to the CLV of CD.

Discs for films were 55 minutes per side!.
 
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