Tempest XY output question?

Jeff F

Well-known member

Donor 12 years: 2011-2022
Joined
Feb 22, 2009
Messages
5,631
Reaction score
216
Location
Johnson City, New York
Is X supposed to be ~14Vpp and Y supposed to be ~16Vpp?

Borrowed an oscilloscope from a co-worker and that's what I'm getting out of a board I've been working on... you can even see the screen on the o-scope...
attachment.php


attachment.php


attachment.php


Now I just have to get the monitor working 100%. If I don't hear back from someone regarding those XY measurements... I'm going to Tim I's to plug my board into his machine just to make sure it's working. I was going to bring the monitor too but I'm thinking the board is good now... it stinks when you aren't sure if your board AND your monitor are working correctly. :D
 

Attachments

  • Tempest-osc01.jpg
    Tempest-osc01.jpg
    19.7 KB · Views: 195
  • Tempest-osc02.jpg
    Tempest-osc02.jpg
    16.9 KB · Views: 195
  • Tempest-osc03.jpg
    Tempest-osc03.jpg
    18.1 KB · Views: 193
Last edited:
I don't know what the measurements are supposed to be off the top of my head, but since you can see the game, it is pretty good chance that there is no problem with the signal levels on your board.

BTW - What scope is that? Looks like an Owon? There is another O-scope thread going on and I just asked about those since they are $300.

http://www.equipmatching.com/uploads/images/1198662076.jpg

-VJ
 
Yeah... looks like you've got good output from the board. Must be the monitor now. Do you have HV? Can you hear the chatter?
 
Yeah... looks like you've got good output from the board. Must be the monitor now. Do you have HV? Can you hear the chatter?

Yep, have HV and chatter. If I turn to brightness up slightly to overcome the spot killer there is a vertical line on the screen.

I have a cap-kit with transistors I'm going to hopefully do this weekend. Keeping my fingers crossed for sure. :D

[edit]
Forgot to add that the board did indeed test out fine. Thanks again Tim and sorry for keeping you from your dinner! :beerchug:
 
Last edited:
I don't know what the measurements are supposed to be off the top of my head, but since you can see the game, it is pretty good chance that there is no problem with the signal levels on your board.

BTW - What scope is that? Looks like an Owon? There is another O-scope thread going on and I just asked about those since they are $300.

http://www.equipmatching.com/uploads/images/1198662076.jpg

-VJ

Yep, it's an Owon. I replied to that other thread to that I'll do a little writeup on the Owon and the Parallax USB Oscilloscope this weekend(or next).
 
Ok. Good. Vertical line means no vertical deflection (Tempest monitor is in vertical position so if you see a vertical line, the manual will actually call that a horizontal one). This would be a little unusual. Here's a quote from the monitor faq. Perhaps it will help:


Symptom: No X (or Y) deflection


I have seen two deflection boards like this. On one, the problem was that R710 (R610 for Y) was open. How you fry a 10-Watt resistor and nothing else in the circuit is beyond me; perhaps the PCB was dropped and it landed on R710. Anyways, you can test it in circuit and if you do not see a virtual short then replace it. On the other deflection board, the problem was a loose 1/2 watt, 2.2k resistor (R606) in the Y amp. Its intermittent contact was causing the spot killer to flicker, and was causing picture to collapse. The solder joint did NOT look cold or bad, and the resistor tested fine. These resistors take a good deal of heat, and the traces they are on can heat up pretty good. I found that it was loose by pushing on the top of the resistor a bit, and began to hear a "tick" where the resistor lead was touching the solder joint. Probably the trace's temperature (and the resistors heat) caused the resistor lead to separate in the hole on the board, while it still looked and tested fine.
 
If you lost vertical deflection (Y axis), you should always check for cold solder joints on the header pins. That and testing the chassis mount transistors. Since it is vertical deflection that you lost, you should start with the header at J600 (labeled for P600 connector). The two transistors off of that connector are for vertical deflection. You can unplug that connector from the deflection PCB and perform the following test on the transistors from the pins of the cable you unplugged.

These test will tell you if the transistors are good and mounted correctly. Between the transistors and the header pins having cold solder joints, that covers the vast majority of reasons why you loose deflection on the 6100. You can have other bad parts in the Y circuit that also cause it, but those two items are the best place to start.


NPN (2N3716) Test on connector at Pin positions 1, 3, 4 of J100, J600, J700
===========================================================================

Test #1
-------------------
Red -> Pin 3
Black -> Pin 4

Result: .45v to .9v

Test #2
-------------------
Red -> Pin 3
Black -> Pin 1

Result: .45v to .9v

Test #3
-------------------
Red -> Pin 4
Black -> Pin 3

Result: Open

Test #4
-------------------
Red -> Pin 1
Black -> Pin 3

Result: Open

Test #5
-------------------
Red -> Pin 1
Black -> Pin 4

Result: Open

Test #6
-------------------
Red -> Pin 4
Black -> Pin 1

Result: Open



PNP (2N3792) Test on connector at Pin positions 5, 6, 7 of J100, J600, J700
===========================================================================

Test #1
-------------------
Red -> Pin 6
Black -> Pin 5

Result: Open

Test #2
-------------------
Red -> Pin 6
Black -> Pin 7

Result: Open

Test #3
-------------------
Red -> Pin 5
Black -> Pin 6

Result: .45v to .9v

Test #4
-------------------
Red -> Pin 7
Black -> Pin 6

Result: .45v to .9v

Test #5
-------------------
Red -> Pin 7
Black -> Pin 5

Result: Open

Test #6
-------------------
Red -> Pin 5
Black -> Pin 7

Result: Open
 
About 5 minutes after I woke up this morning I just sat behind the Tempest and looked... didn't even have the lights on yet but I was just getting together a little game plan on what I was going to do today.

Guess what jumped out at me...
attachment.php

(wire completely off a transistor)

and

attachment.php

(wires *shoved* into a connector)

Really not sure how I missed those when I had my shop light in there looking around but I did. I just needed to be groggy eyed with almost no light to see those I guess. :D

Those are the first two things on the list today and I'm keeping my fingers crossed.
 

Attachments

  • Tempest-monitorproblem01.jpg
    Tempest-monitorproblem01.jpg
    35.9 KB · Views: 158
  • Tempest-monitorproblem02.jpg
    Tempest-monitorproblem02.jpg
    25.8 KB · Views: 156
"Shot Gun"/"Fix the Obvious" approach didn't work... well... sort of. Spot killer still on. After turning up brightness slightly to overcome spot killer the screen is not a thin horizontal line but rather a horizontal screen only 3" wide.

I did check the two transistors in the harness I fixed so it looks like I'll now check the other four.

Baby steps... baby steps... :D
 
"Shot Gun"/"Fix the Obvious" approach didn't work... well... sort of. Spot killer still on. After turning up brightness slightly to overcome spot killer the screen is not a thin horizontal line but rather a horizontal screen only 3" wide.

I did check the two transistors in the harness I fixed so it looks like I'll now check the other four.

Baby steps... baby steps... :D

Your making good progress. If the image is squished and not collapsed, you may need to adjust all the pots on the game board. There are a couple for placement, size, and other adjustments. I would try the size ones to see if you can get the screen to full size.

Nice progress so far. :)

-VJ
 
Tried it and I can only get it about an inch or so wider and I can almost collapse it to a thin line if I go the other way.

Just looking quick at the manual... seems like Q600 and Q601 could cause what I'm looking at(and maybe even Q602). I notice these aren't included in the parts kit I got from Bob Roberts so before I do any more, I think I'll go down to our local shop and grab a couple replacements(if they have them) before they close for the weekend.

Thanks alot for the help so far Maxstang and VJ! :beerchug:
 
Strange day with this here Tempest... that's for sure...

attachment.php


attachment.php


attachment.php


Big problem today was the MC1495 I replaced a couple days ago came a little loose from the socket sometime between the drive from Tim's house last night and to my house today. And I also have a semi-bad X-width pot on the PCB that needs replacing. (both issues that didn't show themselves last evening when we were testing the board) :(

So... I think the monitor fix today was the wire that was off that transistor and the wire that was just shoved in one of the other transistor connectors.


Still left to figure out is a pretty nasty screen shake. Before I go any further with that I'm going to replace the X and Y width and position pots to make sure it's not any of those. I think *some* of the issue is the X pot because the picture will freak a little when I adjust it.

Baby steps... baby steps...
 

Attachments

  • Tempest-SS01.jpg
    Tempest-SS01.jpg
    20.8 KB · Views: 78
  • Tempest-SS02.jpg
    Tempest-SS02.jpg
    30.5 KB · Views: 79
  • Tempest-SS03.jpg
    Tempest-SS03.jpg
    27 KB · Views: 79
Rock on man!
You'll be a popular guy at your place :)

Did you bail on the road-trip?
cheers
/Tim

Yep, the guy never got back to me to say 100% that he'd be there so I didn't want to chance it. I still haven't heard back from him either so I don't know what's up. :dontknow:

The shake is getting worse on the game and I'm pretty sure it's the monitor since the o-scope shows a pretty solid screen(or as solid as you can tell using one of these cheapo-scopes). :)

Time for the cap-kit... maybe tomorrow... because right now I AM BURNED OUT OF TEMPEST!!! :bigeyes:
 
Great work! Yeah... Cap it and check the voltages on the AR board and set your HV once it's warm.
 
Great work! Yeah... Cap it and check the voltages on the AR board and set your HV once it's warm.

What he said! :)

Congrats on getting to this point... So much easier when you get visual feedback on how it is going.
 
Quick question for you guys with lots of 6101 experience...

My LV section has a resistor and diode combo in position R104 & position R105. From reading some usenet postings and the FAQ it seems that these locations were changed to ZD100 & ZD101 in later revisions... is it alright just to throw the 1N4750 ZDs in place of the resistor/diode combos?

Thanks in advance, :beerchug:
Jeff
 
Quick question for you guys with lots of 6101 experience...

My LV section has a resistor and diode combo in position R104 & position R105. From reading some usenet postings and the FAQ it seems that these locations were changed to ZD100 & ZD101 in later revisions... is it alright just to throw the 1N4750 ZDs in place of the resistor/diode combos?

Thanks in advance, :beerchug:
Jeff

I wouldn't do the modifications in the FAQ now that the LV2000 or LV6100 can be used to replace all of the LV circuitry. Basically why do an old mod when a better one is available for that area. If you just want to replace the components, someone else will have to speak up. I've only use the LV replacement products.
 
Back
Top Bottom