Gravitar WG6100 help (newbie....)

vectordad

New member
Joined
Feb 23, 2010
Messages
5
Reaction score
0
Location
Deerfield, Illinois
Looking for some help. First time post so please bear with me.

I recently picked up an Gravitar. Game worked before I hauled it home. When I got it in the basement and examined it with the back off I noticed resistor R100 on the deflection board smoked on power up. The game still worked even with the resistor very crispy but
seemed silly to leave it that way.

My next step was to search the Internet for info. I ran across articles on marvin3m
on how to bullet proof the video with the addition of a Zanen cap kit, additional parts
recommended in the article, and a LV2000 board. The info I am referring to is here:

http://www.marvin3m.com/video/wg6100.htm

I also went through some more good writeups on vector operation located here:

http://www.ataricade.com/WG_6100_FAQ.pdf
http://arcarc.xmission.com/PDF_Monitors/Atari Monitor TM-183 3rd Printing WG 6100 XY Quadrascan .pdf

I then went ahead and purchased the required parts and set about repairing/upgrading
my game. I've gotten to the point where the game is put back together and the spot killer
light is on. I smell a slight electrical aroma (no smoke though). I've triple checked the 6 button chassis transistors are not shorted to ground and they are not. I've opened up my working Space Duel to verify I've plugged all the connectors on to the various boards correctly. Went thru all the components to verify the correct electrical orientation.

For the tests that indicate the monitor should be disconnected does that mean disconnect
all the high voltage cage wiring except the lead going to the tube and disconnect the neck board or something else?

For the tests that indicate the monitor should be powered on how long is it alright to do
so before doing harm to the monitor or other components?

Appreciate any and all help.

Sean
 
Well, it helps that you have a working Space Duel handy. What I would do right now is swap the deflection board into the Space Duel to see if it works. If it does, then do the same with your HV cage. Once you find out where the problem is, we can move on to fixing it.


Otherwise:

1) Are both lights lit on the LV2000?

2) What is your B+ measured at?

3) What voltage can you measure at the outer cases of the two bottlecap transistors mounted on the right wall?
 
Hi Modessitt,

Thanks for the reply.

Swapped the suspect deflection board in to the Space Duel. Spot Killer is lit.

WRT 1, 2, & 3 all tests done with all cables connected:

1) Are both lights lit on the LV2000?

- Yes

2) What is your B+ measured at?

- Docs say J501 on the neck board is an acceptable place to check. I had 0.8 VDC.

3) What voltage can you measure at the outer cases of the two bottlecap transistors mounted on the right wall?

From back view, right front is -23 VDC and right rear is +25.

Sean
 
there is a connector on the HV cage. There is an orange wire that goes from it to the neckboard. find where it attaches and measure there. You should have about +180vdc. If you aren't even close, you won't have a picture. the adjustment for it is down by a pot inside the HV cage.

i know you said you "replaced the recommended parts". Did you replace all the elctrolytic caps?

Also, there is a black box-shaped part behind P100 on the deflection board. it is called a PTC, and often has cold solder joints on it.

BTW - were the measurements done in the Space Duel or the Gravitar? It seems the problem is in the deflection board. Check the transistors Q603, Q604, Q703, and Q704, and the diodes around them, too....
 
Last edited:
Hi Modessitt,

Been busy at work and at home. Had some time tonight to look at this.



I know you said you "replaced the recommended parts". Did you replace all the elctrolytic caps?

- Believe so, see attached csv text file of parts replaced.

BTW - were the measurements done in the Space Duel or the Gravitar? It seems the problem is in the deflection board. Check the transistors Q603, Q604, Q703, and Q704, and the diodes around them, too....

- The measurements were taken in the Gravitar (the original location of the deflection board).

- I picked up a couple NTE50s and they just arrived. I have the other items already so this weekend I'll check everything you suggest and have spares handy in case needed.


Sean
 

Attachments

  • Gravitar-rebuild.txt
    2.6 KB · Views: 8
that file you attaches is too confusing. i got this (all run-on. this is easier):

,,,
"Component","PCB","PCB #","Notes"
,,,
,,,
"2N3716","Chassis","Q102","Zanen kit"
"2N3792","Chassis","Q103","Zanen kit"
"2N3716","Chassis","Q605","Zanen kit"
"2N3792","Chassis","Q606","Zanen kit"
"2N3716","Chassis","Q705","Zanen kit"
"2N3792","Chassis","Q706","Zanen kit"
,,,
"15 ohm ½ watt","Deflection","R100","Replaced by LV2000"
"15 ohm ½ watt","Deflection","R101","Replaced by LV2000"
"330 ohm ¼ watt","Deflection","R102","Replaced by LV2000"
"330 ohm ¼ watt","Deflection","R103","Replaced by LV2000"
,,,
"1N4148","Deflection","D104","Replaced by LV2000"
"1N4148","Deflection","D105","Replaced by LV2000"
"1N4750 27v","Deflection","ZD100","Replaced by LV2000"
"1N4750 27v","Deflection","ZD101","Replaced by LV2000"
,,,
"MPSA06 (NTE287)","Deflection","Q100","Replaced by LV2000"
"MPSA56 (NTE159)","Deflection","Q101","Replaced by LV2000"
,,,
"NTE49","Deflection","Q604","Replaces MPSU07 (NTE188)"
"NTE49","Deflection","Q704","Replaces MPSU07 (NTE188)"
,,,
"22 ohm 3 watt","Deflection","R106","Replaces 2 watt version"
"1.3K ohm 5 watt","Deflection","R701","Replaces ¼ watt version"
"5.6k ohm ¼","Deflection","R812","Replaces 10k ohm version (only used in P327 & P339)"
"5.6k ohm ¼","Deflection","R813","Replaces 10k ohm version (only used in P327 & P339)"
,,,
"4700 mfd 50v","Deflection","C100",
"4700 mfd 50v","Deflection","C101",
"1 mfd 50v cap","Deflection","C800","Replaces .47 mfd 35v"
"1 mfd 50v cap","Deflection","C801","Replaces .47 mfd 35v"
"1 mfd 50v cap","Deflection","C802","Replaces .47 mfd 35v"
"1 mfd 50v cap","Deflection","C803","Replaces .47 mfd 35v"
,,,
"1N4007 (NTE125) diode","Deflection","D100","Replaces 5A2 (1N4005/NTE116)"
"1N4007 (NTE125) diode","Deflection","D101","Replaces 5A2 (1N4005/NTE116)"
"1N4007 (NTE125) diode","Deflection","D102","Replaces 5A2 (1N4005/NTE116)"
"1N4007 (NTE125) diode","Deflection","D103","Replaces 5A2 (1N4005/NTE116)"
,,,
,,,
"100 mfd 50v","HV cage","C901","Zanen kit"
"100 mfd 50v","HV cage","C902","Zanen kit"
"33 mfd 160v","HV cage","C905","Zanen kit"
"22 mfd 50v","HV cage","C909","Zanen kit"
"10 mfd 350v","HV cage","C910","Zanen kit"
"47 mfd 50v","HV cage","C914","Zanen kit"
,,,
"Z150B diode 150v","HV cage","ZD902","Install at ZD902 not D902 - Zanen kit"
,,,
"MBSA06 (NTE287)","HV cage","Q901","Zanen kit"
"MBSA06 (NTE287)","HV cage","Q902","Zanen kit"
"2N3904","HV cage","Q903","Zanen kit"
,,,
"2.2 ohm 2 watt","HV cage","R901","Zanen kit"
"2.2 ohm 2 watt","HV cage","R902","Zanen kit"
,,,
"3.9 ohm ½ watt","HV cage","R903",
"6.8k ohm ¼ watt","HV cage","R910",
"4.7k ohm ¼ watt","HV cage","R911",
"2.2 ohm 3 watt","HV cage","R926",
,,,
,,,
"33 mfd 250v","Neck board","C503","Zanen kit"
 
Ok, try the B+ measurement I listed above somewhere and see what you get...
 
Back
Top Bottom