Re: Where to start on Missile Command PCB repair

Ok yet another question, 74HXX is a 74 series chip that has a 6ns delay,
can I replace that one that is 3ns such as the LS series of the F series or
does it HAVE to be 6ns?

I apologize for all the questions, but I'm learning a ton right now.

On Fri, Nov 1, 2013 at 9:32 AM, Grant Thienemann <grant.thienemann@gmail.com
> wrote:

> Ok just one more quick clarification, when you are looking at a 74LS
> series chip, they are both 10ns delays, the chips takes considerable less
> power to operate, its not that it can't handle the voltage coming to the IC
> itself right?
>
>
> On Fri, Nov 1, 2013 at 9:31 AM, Kevin Moore <talon.k@gmail.com> wrote:
>
>> I find Digikey tends to run a little higher on some things. I like
>> Newark, Jameco, and occasionally Mouser.
>>
>> Also you can use Findchips.com they exclude Jameco but it will give you a
>> good idea on pricing.
>>
>>
>>
>>
>> On Fri, Nov 1, 2013 at 8:27 AM, Grant Thienemann <
>> grant.thienemann@gmail.com> wrote:
>>
>>> Hey Kevin,
>>>
>>> Thank you for the information! I've never used Jameco before, I've
>>> always used digikey.
>>>
>>> -Grant
>>>
>>>
>>> On Fri, Nov 1, 2013 at 9:26 AM, Kevin Moore <talon.k@gmail.com> wrote:
>>>
>>>> 74S00
>>>>
>>>> http://www.jameco.com/webapp/wcs/stores/servlet/Product_10001_10001_676959_-1
>>>>
>>>>
>>>>
>>>> On Fri, Nov 1, 2013 at 8:24 AM, Grant Thienemann <
>>>> grant.thienemann@gmail.com> wrote:
>>>>
>>>>> Ok lets say you have a 74S00, which is for speed, can you replace that
>>>>> with a 74F00?
>>>>>
>>>>>
>>>>> On Fri, Nov 1, 2013 at 9:17 AM, Grant Thienemann <
>>>>> grant.thienemann@gmail.com> wrote:
>>>>>
>>>>>> Hey Rodger,
>>>>>>
>>>>>> Thank you for the information. I'm looking at wikipedia now about the
>>>>>> 74XX series chips, which would be the default standard when looking to
>>>>>> replace a 7400, or 7404 etc, would that be HTC?
>>>>>>
>>>>>> Thanks
>>>>>> Grant
>>>>>>
>>>>>>
>>>>>> On Fri, Nov 1, 2013 at 9:08 AM, Rodger Boots <rlboots2@gmail.com>wrote:
>>>>>>
>>>>>>> Close. HCT is closer. Either should work.
>>>>>>> On Nov 1, 2013 7:52 AM, "Grant Thienemann" <
>>>>>>> grant.thienemann@gmail.com> wrote:
>>>>>>>
>>>>>>>> Ok not to keep getting off topic, but as this is related to the
>>>>>>>> Missile Command repair, I'm going to ask. When I look for 74191 I can't
>>>>>>>> find anything on Digikey, etc, but when I search for 74HC191 it comes up,
>>>>>>>> is that the same thing?
>>>>>>>>
>>>>>>>>
>>>>>>>> On Fri, Nov 1, 2013 at 8:42 AM, <solarfox@triluminary.net> wrote:
>>>>>>>>
>>>>>>>>> On Fri, 1 Nov 2013 00:35:07 -0400, you wrote:
>>>>>>>>>
>>>>>>>>> >So I can generally replace a 7404 with a 74LS04 without any
>>>>>>>>> problems?
>>>>>>>>>
>>>>>>>>> *Normally*, yes, but there *are* cases where you can run into
>>>>>>>>> problems. The
>>>>>>>>> switching speed of 74LS-series parts isn't *quite* identical to
>>>>>>>>> standard
>>>>>>>>> 7400-series; the propagation delays of a 7404 vs. a 74LS04, for
>>>>>>>>> example:
>>>>>>>>>
>>>>>>>>> -------- 7404 -------- ------- 74LS04 -------
>>>>>>>>> tPLH 12ns (typ) 22ns (max) 9ns (typ) 15ns (max)
>>>>>>>>> tPHL 8ns (typ) 15ns (max) 10ns (typ) 15ns (max)
>>>>>>>>>
>>>>>>>>> (Source: a very dog-eared and well-used copy of "The TTL Data
>>>>>>>>> Book, vol.2",
>>>>>>>>> Texas Instruments, 1985)
>>>>>>>>>
>>>>>>>>> The difference is, admittedly, pretty small, but it can add up
>>>>>>>>> when you've
>>>>>>>>> got signals flowing through a bunch of different gates, or when
>>>>>>>>> you've got
>>>>>>>>> a more complex chip (such as the 74191). So, depending on the
>>>>>>>>> circuit in
>>>>>>>>> question, there's a small (but non-zero) chance that you *could*
>>>>>>>>> end up
>>>>>>>>> with a "race" condition by swapping a 74LS part into a circuit
>>>>>>>>> full of
>>>>>>>>> 7400-series chips.
>>>>>>>>>
>>>>>>>>> --------------------------------------------------------------------------
>>>>>>>>> "I thought I told you to look after him!"
>>>>>>>>>
>>>>>>>>> "He'll be all right; he's a Time Lord."
>>>>>>>>>
>>>>>>>>> "That's just what they're _called_; it doesn't mean he actually
>>>>>>>>> knows what
>>>>>>>>> he's _doing!_"
>>>>>>>>>
>>>>>>>>> --------------------------------------------------------------------------
>>>>>>>>> solarfox@triluminary.net (Gary
>>>>>>>>> Akins jr.)
>>>>>>>>>
>>>>>>>>> --------------------------------------------------------------------------
>>>>>>>>>
>>>>>>>>>
>>>>>>>>> ---------------------------------------------------------------------------
>>>>>>>>> ** Unsubscribe, subscribe, or view the archives at
>>>>>>>>> http://www.vectorlist.org
>>>>>>>>> ** Please direct other questions, comments, or problems to
>>>>>>>>> chris@westnet.com
>>>>>>>>>
>>>>>>>>
>>>>>>>>
>>>>>>
>>>>>
>>>>
>>>
>>
>

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Received on Fri Nov 1 09:46:06 2013