Re: Where to start on Missile Command PCB repair

Hey Rodger,

That's not a problem though right? Also how accurate does the delay have to
be?

Thanks
Grant

On Fri, Nov 1, 2013 at 10:13 AM, Rodger Boots <rlboots2@gmail.com> wrote:

> Draws less current.
> On Nov 1, 2013 8:33 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 10:18:58 2013