From Newsgroup: rec.games.pinball

Hi All,
I am working on a R&B with only the Svuk coil not firing. Starting with the coil. It is wired correctly and another coil was tested and did not fire. Good diode. 74volts at both lugs. The switch is read. Took a look at all the coils daisy chained properly. Moving back to PPB board. All fuses are good. Q3 is good, associated diodes and resistors are good. Driver board, Q 42 is good. Smaller 2n4401 transistor is good. Resistors good. 7408 reads good. Checked for cold solder joints. No loose or broken wires at the connectors.
Frankly, I am stumped. All coils fire except SVUK. Is there anything I am missing? Could it be a bad pin on the PIA.
Any help appreciated.
Thanks,
Craig
CARGPB23
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From Newsgroup: rec.games.pinball

On Friday, November 6, 2020 at 12:32:52 PM UTC-5, craigwe...@gmail.com wrote:

Hi All,

I am working on a R&B with only the Svuk coil not firing. Starting with the coil. It is wired correctly and another coil was tested and did not fire. Good diode. 74volts at both lugs. The switch is read. Took a look at all the coils daisy chained properly. Moving back to PPB board. All fuses are good. Q3 is good, associated diodes and resistors are good. Driver board, Q 42 is good. Smaller 2n4401 transistor is good. Resistors good. 7408 reads good. Checked for cold solder joints. No loose or broken wires at the connectors.
Frankly, I am stumped. All coils fire except SVUK. Is there anything I am missing? Could it be a bad pin on the PIA.

Any help appreciated.

Thanks,

Craig
CARGPB23

More than likely a bad TIP36 on the PPB board. Is it actually Q3 that controls it? Lots of errors in DE manuals.
Jim
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From Newsgroup: rec.games.pinball

On Friday, November 6, 2020 at 12:47:47 PM UTC-5, Gott Lieb? wrote:

On Friday, November 6, 2020 at 12:32:52 PM UTC-5, craigwe...@gmail.com wrote:

Hi All,

I am working on a R&B with only the Svuk coil not firing. Starting with the coil. It is wired correctly and another coil was tested and did not fire. Good diode. 74volts at both lugs. The switch is read. Took a look at all the coils daisy chained properly. Moving back to PPB board. All fuses are good. Q3 is good, associated diodes and resistors are good. Driver board, Q 42 is good. Smaller 2n4401 transistor is good. Resistors good. 7408 reads good. Checked for cold solder joints. No loose or broken wires at the connectors.
Frankly, I am stumped. All coils fire except SVUK. Is there anything I am missing? Could it be a bad pin on the PIA.

Any help appreciated.

Thanks,

Craig
CARGPB23

More than likely a bad TIP36 on the PPB board. Is it actually Q3 that controls it? Lots of errors in DE manuals.

Jim

Super VUK is Q4 according to schems.
Jim
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From Newsgroup: rec.games.pinball

On Friday, November 6, 2020 at 9:47:47 AM UTC-8, Gott Lieb? wrote:

On Friday, November 6, 2020 at 12:32:52 PM UTC-5, craigwe...@gmail.com wrote:

Hi All,

I am working on a R&B with only the Svuk coil not firing. Starting with the coil. It is wired correctly and another coil was tested and did not fire. Good diode. 74volts at both lugs. The switch is read. Took a look at all the coils daisy chained properly. Moving back to PPB board. All fuses are good. Q3 is good, associated diodes and resistors are good. Driver board, Q 42 is good. Smaller 2n4401 transistor is good. Resistors good. 7408 reads good. Checked for cold solder joints. No loose or broken wires at the connectors.
Frankly, I am stumped. All coils fire except SVUK. Is there anything I am missing? Could it be a bad pin on the PIA.

Any help appreciated.

Thanks,

Craig
CARGPB23

More than likely a bad TIP36 on the PPB board. Is it actually Q3 that controls it? Lots of errors in DE manuals.

Jim

I checked all of the TIP 36c on PPB board. All checked good. They all read the same. Usually, a bad tip 36c gives either 0000 on the DMM or something like 0.100.
The one thing that I failed to do was to check the path back to the 7408 but the board had never been worked on so I am assuming that the path was good. Yeah, I didnt have a very good schematic and it looked like the customer had photocopied it from the internet. I asked him to order one from PBR.
But I have an email iinto to Stern since they dont answer the phone any longer. But have not heard back from them. I do not want to shotgun this, I would rather just find the problem. but thanks for your input.
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From Newsgroup: rec.games.pinball

On 11/6/2020 3:30 PM, craigwe...@gmail.com wrote:

On Friday, November 6, 2020 at 9:47:47 AM UTC-8, Gott Lieb? wrote:

On Friday, November 6, 2020 at 12:32:52 PM UTC-5, craigwe...@gmail.com wrote:

Hi All,

I am working on a R&B with only the Svuk coil not firing. Starting with the coil. It is wired correctly and another coil was tested and did not fire. Good diode. 74volts at both lugs. The switch is read. Took a look at all the coils daisy chained properly. Moving back to PPB board. All fuses are good. Q3 is good, associated diodes and resistors are good. Driver board, Q 42 is good. Smaller 2n4401 transistor is good. Resistors good. 7408 reads good. Checked for cold solder joints. No loose or broken wires at the connectors.
Frankly, I am stumped. All coils fire except SVUK. Is there anything I am missing? Could it be a bad pin on the PIA.

Any help appreciated.

Thanks,

Craig
CARGPB23

More than likely a bad TIP36 on the PPB board. Is it actually Q3 that controls it? Lots of errors in DE manuals.

Jim

I checked all of the TIP 36c on PPB board. All checked good. They all read the same. Usually, a bad tip 36c gives either 0000 on the DMM or something like 0.100.

The one thing that I failed to do was to check the path back to the 7408 but the board had never been worked on so I am assuming that the path was good. Yeah, I didnt have a very good schematic and it looked like the customer had photocopied it from the internet. I asked him to order one from PBR.

But I have an email iinto to Stern since they dont answer the phone any longer. But have not heard back from them. I do not want to shotgun this, I would rather just find the problem. but thanks for your input.

What happens if you ground the tab of the transistor that controls it?
If it fires, you wiring is good, if it doesn't then something wrong w/
the wiring.

Paul
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From Newsgroup: rec.games.pinball

On Friday, November 6, 2020 at 8:12:15 PM UTC-8, Paul wrote:

On 11/6/2020 3:30 PM, craigwe...@gmail.com wrote:

On Friday, November 6, 2020 at 9:47:47 AM UTC-8, Gott Lieb? wrote:

On Friday, November 6, 2020 at 12:32:52 PM UTC-5, craigwe...@gmail.com wrote:

Hi All,

I am working on a R&B with only the Svuk coil not firing. Starting with the coil. It is wired correctly and another coil was tested and did not fire. Good diode. 74volts at both lugs. The switch is read. Took a look at all the coils daisy chained properly. Moving back to PPB board. All fuses are good. Q3 is good, associated diodes and resistors are good. Driver board, Q 42 is good. Smaller 2n4401 transistor is good. Resistors good. 7408 reads good. Checked for cold solder joints. No loose or broken wires at the connectors.
Frankly, I am stumped. All coils fire except SVUK. Is there anything I am missing? Could it be a bad pin on the PIA.

Any help appreciated.

Thanks,

Craig
CARGPB23

More than likely a bad TIP36 on the PPB board. Is it actually Q3 that controls it? Lots of errors in DE manuals.

Jim

I checked all of the TIP 36c on PPB board. All checked good. They all read the same. Usually, a bad tip 36c gives either 0000 on the DMM or something like 0.100.

The one thing that I failed to do was to check the path back to the 7408 but the board had never been worked on so I am assuming that the path was good. Yeah, I didnt have a very good schematic and it looked like the customer had photocopied it from the internet. I asked him to order one from PBR.

But I have an email iinto to Stern since they dont answer the phone any longer. But have not heard back from them. I do not want to shotgun this, I would rather just find the problem. but thanks for your input.

What happens if you ground the tab of the transistor that controls it?
If it fires, you wiring is good, if it doesn't then something wrong w/
the wiring.

Paul

When I grounded the tab of the transistor nothing fires. There is also no voltage at the tab. The other VUK has 74Volts and the other tabs have 40V and fire when grounded.
I once had a problem like this on a Gilligans a long time ago. The TIP checked good but the kickback wouldnt fire. I finally decided to replace the TIP for the kickback and it fired. So, I am thinking I may just need to replace the TIP 36C and the 122, 2n4401. But if I do that and it still wont fire, Well then I just invested a little more time to it.
I am awaiting an email back from Stern on this.
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From Newsgroup: rec.games.pinball

On Friday, November 6, 2020 at 3:31:02 PM UTC-5, craigwe...@gmail.com wrote:

On Friday, November 6, 2020 at 9:47:47 AM UTC-8, Gott Lieb? wrote:

On Friday, November 6, 2020 at 12:32:52 PM UTC-5, craigwe...@gmail.com wrote:

Hi All,

I am working on a R&B with only the Svuk coil not firing. Starting with the coil. It is wired correctly and another coil was tested and did not fire. Good diode. 74volts at both lugs. The switch is read. Took a look at all the coils daisy chained properly. Moving back to PPB board. All fuses are good. Q3 is good, associated diodes and resistors are good. Driver board, Q 42 is good. Smaller 2n4401 transistor is good. Resistors good. 7408 reads good. Checked for cold solder joints. No loose or broken wires at the connectors.
Frankly, I am stumped. All coils fire except SVUK. Is there anything I am missing? Could it be a bad pin on the PIA.

Any help appreciated.

Thanks,

Craig
CARGPB23

More than likely a bad TIP36 on the PPB board. Is it actually Q3 that controls it? Lots of errors in DE manuals.

Jim

I checked all of the TIP 36c on PPB board. All checked good. They all read the same. Usually, a bad tip 36c gives either 0000 on the DMM or something like 0.100.

The one thing that I failed to do was to check the path back to the 7408 but the board had never been worked on so I am assuming that the path was good. Yeah, I didnt have a very good schematic and it looked like the customer had photocopied it from the internet. I asked him to order one from PBR.

But I have an email iinto to Stern since they dont answer the phone any longer. But have not heard back from them. I do not want to shotgun this, I would rather just find the problem. but thanks for your input.

Good luck with Stern! I'm waiting on an email that was sent 8 or 9 weeks ago. I know Chaz's passing backed things up, but this is ridiculous.
Jim
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