Flashes 4 times then stops. I have changed U17 and U4 as the repair guide states. I have tested continuity from all pins, I also went backward to U5 and changed that. Still, only 4 flashes. Any suggestions are appreciated.
On 2022/03/02 4:01 a.m., gtr...@yahoo.com wrote:
Flashes 4 times then stops. I have changed U17 and U4 as the repair guide states. I have tested continuity from all pins, I also went backward to U5 and changed that. Still, only 4 flashes. Any suggestions are appreciated.You need a Logic Probe or Oscilloscope at this point.
Check inputs to U14 - pins 20 through 23 - they should all be pulsing.
If good then check U14 outputs pins 14 - 17 inclusive, again they should
be pulsing.
If bad, check U17 pins 37 through 40 inclusive, are they all pulsing? If yes, then there is a connection problem between U17 and U14 pins. If no, then do a continuity check to ground or Vcc on those four pins - any
shorted to ground or Vcc?
I have a Game Plan pinball support page (added the above to) here:
https://flippers.com/gameplanTips.html
John :-#)#
--
(Please post followups or tech inquiries to the USENET newsgroup)
John's Jukes Ltd.
MOVED to #7 - 3979 Marine Way, Burnaby, BC, Canada V5J 5E3
(604)872-5757 (Pinballs, Jukes, Video Games)
www.flippers.com
"Old pinballers never die, they just flip out."
On Wednesday, March 2, 2022 at 10:05:53 AM UTC-5, John Robertson wrote:
On 2022/03/02 4:01 a.m., gtr...@yahoo.com wrote:
Flashes 4 times then stops. I have changed U17 and U4 as the repair guide states. I have tested continuity from all pins, I also went backward to U5 and changed that. Still, only 4 flashes. Any suggestions are appreciated.You need a Logic Probe or Oscilloscope at this point.
Check inputs to U14 - pins 20 through 23 - they should all be pulsing.
If good then check U14 outputs pins 14 - 17 inclusive, again they should be pulsing.
If bad, check U17 pins 37 through 40 inclusive, are they all pulsing? If yes, then there is a connection problem between U17 and U14 pins. If no, then do a continuity check to ground or Vcc on those four pins - any shorted to ground or Vcc?
I have a Game Plan pinball support page (added the above to) here:
https://flippers.com/gameplanTips.html
John :-#)#
--Hello John, Thank you for the suggestions.
(Please post followups or tech inquiries to the USENET newsgroup)
John's Jukes Ltd.
MOVED to #7 - 3979 Marine Way, Burnaby, BC, Canada V5J 5E3
(604)872-5757 (Pinballs, Jukes, Video Games)
www.flippers.com
"Old pinballers never die, they just flip out."
Here is where I am at as of 11pm last night.
Everything you mentioned is good except, U14 pin 2 is being pulled to ground.
This does not happen on a known good board.
U14 pin 2 goes to U19 pin 12 and then to U21 pin 1.
At that point I went to bed.
I have to work on a car this morning and later I will get back to this.
Regards
George
On Thursday, March 3, 2022 at 6:35:36 AM UTC-5, gtriley@yahoo.com wrote:
On Wednesday, March 2, 2022 at 10:05:53 AM UTC-5, John Robertson wrote:
On 2022/03/02 4:01 a.m., gtr...@yahoo.com wrote:Hello John, Thank you for the suggestions.
Flashes 4 times then stops. I have changed U17 and U4 as the repair guide states. I have tested continuity from all pins, I also went backward to U5 and changed that. Still, only 4 flashes. Any suggestions are appreciated.You need a Logic Probe or Oscilloscope at this point.
Check inputs to U14 - pins 20 through 23 - they should all be pulsing.
If good then check U14 outputs pins 14 - 17 inclusive, again they should >>> be pulsing.
If bad, check U17 pins 37 through 40 inclusive, are they all pulsing? If >>> yes, then there is a connection problem between U17 and U14 pins. If no, >>> then do a continuity check to ground or Vcc on those four pins - any
shorted to ground or Vcc?
I have a Game Plan pinball support page (added the above to) here:
https://flippers.com/gameplanTips.html
John :-#)#
--
Here is where I am at as of 11pm last night.
Everything you mentioned is good except, U14 pin 2 is being pulled to ground.
This does not happen on a known good board.
U14 pin 2 goes to U19 pin 12 and then to U21 pin 1.
At that point I went to bed.
I have to work on a car this morning and later I will get back to this.
Regards
George
7pm update.
U21 was bad which was causing pin 2 of U14 to go to ground.
Replaced it with a new 74LS379.
Still 4 flashes, but now the displays show a number 7 in all 5 displays.
On 2022/03/03 4:11 p.m., gtr...@yahoo.com wrote:
On Thursday, March 3, 2022 at 6:35:36 AM UTC-5, gtr...@yahoo.com wrote:
On Wednesday, March 2, 2022 at 10:05:53 AM UTC-5, John Robertson wrote: >>> On 2022/03/02 4:01 a.m., gtr...@yahoo.com wrote:
Hello John, Thank you for the suggestions.Flashes 4 times then stops. I have changed U17 and U4 as the repair guide states. I have tested continuity from all pins, I also went backward to U5 and changed that. Still, only 4 flashes. Any suggestions are appreciated.You need a Logic Probe or Oscilloscope at this point.
Check inputs to U14 - pins 20 through 23 - they should all be pulsing. >>>
If good then check U14 outputs pins 14 - 17 inclusive, again they should >>> be pulsing.
If bad, check U17 pins 37 through 40 inclusive, are they all pulsing? If >>> yes, then there is a connection problem between U17 and U14 pins. If no, >>> then do a continuity check to ground or Vcc on those four pins - any
shorted to ground or Vcc?
I have a Game Plan pinball support page (added the above to) here:
https://flippers.com/gameplanTips.html
John :-#)#
--
Here is where I am at as of 11pm last night.
Everything you mentioned is good except, U14 pin 2 is being pulled to ground.
This does not happen on a known good board.
U14 pin 2 goes to U19 pin 12 and then to U21 pin 1.
At that point I went to bed.
I have to work on a car this morning and later I will get back to this. >>
Regards
George
7pm update.Hi George,
U21 was bad which was causing pin 2 of U14 to go to ground.
Replaced it with a new 74LS379.
Still 4 flashes, but now the displays show a number 7 in all 5 displays.
That is odd, normally displays do not come alive until the last flash.
Was there any corrosion on the motherboard? I'd be checking for traces
that have given up.
John :-#)#
--
(Please post followups or tech inquiries to the USENET newsgroup)
John's Jukes Ltd.
MOVED to #7 - 3979 Marine Way, Burnaby, BC, Canada V5J 5E3
(604)872-5757 (Pinballs, Jukes, Video Games)
www.flippers.com
"Old pinballers never die, they just flip out."
On Friday, March 11, 2022 at 1:03:27 PM UTC-5, John Robertson wrote:
On 2022/03/03 4:11 p.m., gtr...@yahoo.com wrote:
On Thursday, March 3, 2022 at 6:35:36 AM UTC-5, gtr...@yahoo.com wrote:
On Wednesday, March 2, 2022 at 10:05:53 AM UTC-5, John Robertson wrote: >>> On 2022/03/02 4:01 a.m., gtr...@yahoo.com wrote:
Hello John, Thank you for the suggestions.Flashes 4 times then stops. I have changed U17 and U4 as the repair guide states. I have tested continuity from all pins, I also went backward to U5 and changed that. Still, only 4 flashes. Any suggestions are appreciated.You need a Logic Probe or Oscilloscope at this point.
Check inputs to U14 - pins 20 through 23 - they should all be pulsing. >>>
If good then check U14 outputs pins 14 - 17 inclusive, again they should
be pulsing.
If bad, check U17 pins 37 through 40 inclusive, are they all pulsing? If
yes, then there is a connection problem between U17 and U14 pins. If no,
then do a continuity check to ground or Vcc on those four pins - any >>> shorted to ground or Vcc?
I have a Game Plan pinball support page (added the above to) here:
https://flippers.com/gameplanTips.html
John :-#)#
--
Here is where I am at as of 11pm last night.
Everything you mentioned is good except, U14 pin 2 is being pulled to ground.
This does not happen on a known good board.
U14 pin 2 goes to U19 pin 12 and then to U21 pin 1.
At that point I went to bed.
I have to work on a car this morning and later I will get back to this. >>
Regards
George
7pm update.Hi George,
U21 was bad which was causing pin 2 of U14 to go to ground.
Replaced it with a new 74LS379.
Still 4 flashes, but now the displays show a number 7 in all 5 displays.
That is odd, normally displays do not come alive until the last flash.
Was there any corrosion on the motherboard? I'd be checking for traces that have given up.
John :-#)#
--No corrosion at all, that is what bothers me.
(Please post followups or tech inquiries to the USENET newsgroup)
John's Jukes Ltd.
MOVED to #7 - 3979 Marine Way, Burnaby, BC, Canada V5J 5E3
(604)872-5757 (Pinballs, Jukes, Video Games)
www.flippers.com
"Old pinballers never die, they just flip out."
Continuity, good everywhere I check.
One number 7 comes up in all displays.
Flashes 4 times then stops every time.
On Saturday, March 12, 2022 at 7:01:56 AM UTC-5, gtriley@yahoo.com wrote:
On Friday, March 11, 2022 at 1:03:27 PM UTC-5, John Robertson wrote:
On 2022/03/03 4:11 p.m., gtr...@yahoo.com wrote:No corrosion at all, that is what bothers me.
On Thursday, March 3, 2022 at 6:35:36 AM UTC-5, gtr...@yahoo.com wrote: >>>>> On Wednesday, March 2, 2022 at 10:05:53 AM UTC-5, John Robertson wrote: >>>>>> On 2022/03/02 4:01 a.m., gtr...@yahoo.com wrote:
Hello John, Thank you for the suggestions.Flashes 4 times then stops. I have changed U17 and U4 as the repair guide states. I have tested continuity from all pins, I also went backward to U5 and changed that. Still, only 4 flashes. Any suggestions are appreciated.You need a Logic Probe or Oscilloscope at this point.
Check inputs to U14 - pins 20 through 23 - they should all be pulsing. >>>>>>
If good then check U14 outputs pins 14 - 17 inclusive, again they should >>>>>> be pulsing.
If bad, check U17 pins 37 through 40 inclusive, are they all pulsing? If >>>>>> yes, then there is a connection problem between U17 and U14 pins. If no, >>>>>> then do a continuity check to ground or Vcc on those four pins - any >>>>>> shorted to ground or Vcc?
I have a Game Plan pinball support page (added the above to) here: >>>>>>
https://flippers.com/gameplanTips.html
John :-#)#
--
Here is where I am at as of 11pm last night.
Everything you mentioned is good except, U14 pin 2 is being pulled to ground.
This does not happen on a known good board.
U14 pin 2 goes to U19 pin 12 and then to U21 pin 1.
At that point I went to bed.
I have to work on a car this morning and later I will get back to this. >>>>>
Regards
George
7pm update.
U21 was bad which was causing pin 2 of U14 to go to ground.
Replaced it with a new 74LS379.
Still 4 flashes, but now the displays show a number 7 in all 5 displays. >>> Hi George,
That is odd, normally displays do not come alive until the last flash.
Was there any corrosion on the motherboard? I'd be checking for traces
that have given up.
John :-#)#
--
(Please post followups or tech inquiries to the USENET newsgroup)
John's Jukes Ltd.
MOVED to #7 - 3979 Marine Way, Burnaby, BC, Canada V5J 5E3
(604)872-5757 (Pinballs, Jukes, Video Games)
www.flippers.com
"Old pinballers never die, they just flip out."
Continuity, good everywhere I check.
One number 7 comes up in all displays.
Flashes 4 times then stops every time.
A bad 7417
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