Re: TECH: Battlezone G05-805 monitor - still having problems

Hi all,

I finally got back out to the workshop and did some measurements on the monitor while the game was running. Roughly, all the voltages are a little low. Here is the rundown:

40 VDC (measured at F102) ~ 33 VDC (this goes to the EHT)
30 VAC measured at F100 & F101 ~ 27.6 VAC Each (this is input from the harness to the monitor)
34 VDC for the B+ measured at Pin 1 on connector P600 and P700: ~32 VDC

And the big find of the day is that

90 VDC measured at Pin 1 on P500 starts at close to 90 VDC, but then after about 15 minutes of warm-up, has dropped to around 70 VDC!
The high voltage measured at the anode starts out at about 12 KV (about normal), but after the warm-up, is down to about 9.3 KV.
At this time, the monitor has went into full bloom. None of the other voltage drop.

Another thing I found is that my schematic for the HV cage PCB is not correct in the monitor manual. The HV PCB layout says P900 PCB in the manual, but the actual HV PCB says P300. Anyone got the correct schematic? Things just don't match up between the two...

Still looking for the problem, but at least I am on the trail again. Comments?

RODGER: Sorry for the misspelling my friend - from your response you must get a good bit of that. :-) Thanks for the help.

Regards,
-Commander Dave

----- Original Message -----
  From: Rodger Boots
  To: vectorlist@synthcom.com
  Sent: Wednesday, October 09, 2002 02:46 AM
  Subject: Re: VECTOR: TECH: Battlezone G05-805 monitor - still having problems

  Commander Dave wrote:

    ALL: Thanks for the tips. I will be getting back to testing later this week.

    Roger: Can you tell me how to test this diode (ZD901)? Will it test with a meter on the diode setting? What should I look for?

  It's Rodger, damn it!

  The only real way to test it is to measure the voltage across it (56 volts) with the power supply running.
  If you don't trust yourself doing this get some clip leads ('Shack has them) so the meter can be connected without you holding the leads.

    Peter: I'll check the voltages coming into the monitor and see if it changes after warm-up. I guess that I should have checked all the other voltages to see if they drop as well. Thanks.

    John: Those small caps you mentioned... what style are they? If they are the can style electrolytics, then I believe all were replaced.. but I will double check. If they are not the radial type, let me know.

    Again, thanks to all.

    -Commander Dave
      ----- Original Message -----
      From: Rodger Boots
      To: vectorlist@synthcom.com
      Sent: Sunday, October 06, 2002 16:20 PM
      Subject: Re: VECTOR: TECH: Battlezone G05-805 monitor - still having problems

      My best guess, ZD901, the 56 volt zener.

      Commander Dave wrote:

        Hello all,

        Yes, these are the postings that never end. I am getting so disgusted with this G05-805. I was able to get a working HV diode and the problem of shaking and blooming still shows up. When powered up totally cold, the HV is fine, maybe even a little over. The image on the monitor,however, has a very small case of the shakes and as it warms up the HV (about 5 minutes or less), the image starts to expand and the HV starts to drop. It was down to 10.8 KV when I got disgusted, cut the power and left.
        <<snip>>

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Received on Wed Oct 9 07:23:27 2002