Need to replace one on my f-14 tomcat....but confused on all the different alphabet 7402 types? Which do i need? ....Which to stayaway from? Suggestions on where to buy?

Thanks

#2 12 months ago

???

JethroP

Pinside+ Frequent

6y 101K 3,136 9 14 1

What is the part description in the game manual?

#3 12 months ago

???

pevo

Pinside member

Temple, TX

1y 31,800 278 6

heres the application.

Theres so many different ones. Plus there is conflicting advice on which 7402 chip to use

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#4 12 months ago

GPE

U50 has 560 ohm pullups to 5V (see above in drawing to Q76 & Q78). This means the part must 'sink' 9mA (8.92mA) to ground. For this - use 7402, 74F02 or 74S02. 74F02 and 74S02 are power hogs, no need to load the frail 5V regulator any more than you have to. Don't use 74HCT02 or 74HC02 since they are intended to sink a lower level of output output current. 74LS02 is close but designed to sink up to 8mA to ground.

Mouser, Digikey, Newark and a few others.
Avoid aliexpress, ebay and amazon - you might get remarks of a lesser part.

#5 12 months ago

RIC

rickeve

Pinside member

Canton, OH

9y 27,050 51 6

Great to see you are still around Ed

#6 12 months ago

CRD

chad

Game Guy

11y 140K 15,229 9 4

Quoted from G-P-E:
SN7402N.
U50 has 560 ohm pullups to 5V (see above in drawing to Q76 & Q78). This means the part must 'sink' 9mA (8.92mA) to ground. For this - use 7402, 74F02 or 74S02. 74F02 and 74S02 are power hogs, no need to load the frail 5V regulator any more than you have to. Don't use 74HCT02 or 74HC02 since they are intended to sink a lower level of output output current. 74LS02 is close but designed to sink up to 8mA to ground.
Mouser, Digikey, Newark and a few others.
Avoid aliexpress, ebay and amazon - you might get remarks of a lesser part.

@G-P-E, were you able to find a buyer for the business yet??

#7 11 months ago

GPE

G-P-E

GPE

Omaha, NE

13y 76,800 2,778 4

Been working / traveling so much for my other job that I have not had the time. Trying to get inventory complete before my next excursion comes up in a few weeks. Slowly (very slowly) but surely getting there.

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