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ejthedj 18th April 2012 06:32 AM

Flip-flop info
In the early 70's, I got some flip-flops made by Motorola. HEP583. I have a book of projects and some projects use these so I have some info about them, namely the pin-out and the supply voltage they used in those projects. I was hoping someone here would have either a datasheet or some info written down. I would like to know the min. and max. supply voltage, the max input voltage, and if possible, a truth table would be nice since none of the projects in the book I have make use of one of the pins. It's labeled C/d which I believe is Clear/direct input. had minimal info on them. They also claim it's a J-K flip but there is no J or K input, only a Set, Clear, and Clear/d. I know, some of you would say just toss them and use modern ones, but I have over a dozen of them and would like to try and use them. All the other hits I got doing a web search was companies selling them but none had info about them, they didn't even list a price, just a request for a quote. Any help would be appriciated. Thanks.


sofaspud 18th April 2012 07:14 AM

Yeah that's a dinosaur alright. American Microsemi's webpage says it's a single J-K flip-flop using RTL logic and a nominal supply voltage of 4V. Another page says it's the same as a HEP C2009G. I checked 3 cross refs offline and came up empty.

<edit> The HEP prefix is Hobbyist-Experimental-Prototype. I've found that MC782G is the main part designator. Hope that helps.

Enzo 18th April 2012 08:04 AM

Wwow, HEP parts. As I recall HEP was Moto's version of ECG, which we know today mainly as NTE, which is to say a general replacement line. HEP parts were copies or simply relabels of generic parts. Much as I hate NTE and the like, I do keeop their catalogs around for identifying odd things. Unfortunately, HEP583 is not in the NTE or ECG lookup.

And also WOW, RTL. Somewher I have a pile of RTL chips. I had a series of Rockola wallboxes that ran on RTL logic, and I stocked the darn things. DOubt I will ever use a one of them again at this point.

And somewhere I have a master HEP guide, but lord in heaven only knows where I put it. Somewher out in my warehouse.

sofaspud 18th April 2012 08:21 AM

I just remembered... before Don "Guru" Lancaster wrote his TTL, CMOS, and Active Filter Cookbooks, he wrote The RTL Cookbook. He's generously scanned and hosted it at his website as a downloadable pdf. It's probably your best reference for using those chips. (I think RTL went out of style with first generation electronic calculators :))

indianajo 18th April 2012 02:49 PM

I've got a Motorola RTL databook up in the attic but it is pretty well buried. Nowhere I worked used them when I was there. The only second source to Motorola I think was Sprague semiconductor, which was a very short lived operation. I think a fellow tech told me when saw me salvaging the book he pitched out that they weren't real stable to temperature variations, or something. HEP was the consumer storefront designation, I think the real industrial part numbers were 800 series.

ejthedj 18th April 2012 06:15 PM

Eureka, the RTL Cookbook link posted by sofaspud is just what I needed to fill in the gaps, plus some. Thank you.:p It even describes the functions of the inputs. Lots of good info in there. I gather from all my web surfing that in order to be a J-K flip-flop, it doesn't have to have inputs called J and K, just so it performs as one.

I realise that if doing a serious project requiring J-K flip flops, there are much better ones out now, with all the datasheets, but I found a schematic for a simple transistor checker which uses a single flip-flop and 555 timer and it determines the EBC pins and whether NPN or PNP. It uses voltage so low it won't damage the transistor being tested even if wired wrong. I have over 100 transistors same size as 2N3904's etc. but they all have an in-house part number with no cross reference. Even if RTL uses a lot of power, the tester won't be in use for long periods anyway, just long enough to test those transistors. Anyway, thanks for the help.


Enzo 18th April 2012 11:02 PM

Cool, glad you got what you needed.

I went into my warehouse on the way to work today and found my old HEP guides. The thicker Databook and Selector guide, plus the cross reference catalog. Now that we don;t need them, I guess they can live on my shelf here.

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