« previous next »
Pages: [1]

Author Topic: Nanao MS-2934s with jittery picture, bloom  (Read 258 times)

Offline Spicules

  • Level 7: Khaaaan!
  • *****
  • Join Date: Jun 2012
  • Location: Panama City, FL
  • Posts: 1093
  • Mission COMPRETE !!!
Nanao MS-2934s with jittery picture, bloom
« on: November 28, 2022, 04:56:14 AM »
29/27" Nanao Ms-2934 31k monitor is in my Sega Naomi Universal.

Previously replaced the caps and repaired loose connections on the vert ic when it had vertical collapse.

Now, the picture shrinks during bright scenes (bright explosions, times when screen comes up all white, etc).

Also, seems to be sort of vibrating, or moving left/right quickly.

I've never had to adjust vertical/horizontal sync on this monitor (it doesn't have that adjust on the adjust board, but does on the chassis) but that is not causing the issue and does not help.

The service manuals are practically useless for this model and no one seems to have much info out there, so
Thinking to replace the filter cap and the volt. reg. ic as a starting point, but wondering if anyone has any advice on this one.

In this video, you can see the picture shifting left/right, then shrink when it goes to a white splash screen.

Logged
Vids:
"Chewlix" Vewlix knockoff; Dynamo HS-27 w/ Area 51/MaxForce;  Strider (DE "Commando" conversion) ; Centipede Cabaret;  Tempest,  Irem "Madonna" ; Sega Blast City w/ MisterFPGA; Shinobi (Track&Field Conversion) ; Sega Naomi Universal with Piforce/Net Dimm;

WTB/WTT: HOTD2 Dedicated; candy cab or candy knockoffs; Outrun cabaret

- I am a former TV tech and can repair and re-cap CRT and LCD monitors in my area.

Offline HammysHangout ( Hammy )

  • Mad Sciencetist
  • Administrator
  • Level 10: Timelord
  • *****
  • Join Date: Nov 2008
  • Location: Hamster Land, Brandon, FL
  • Posts: 12449
    • Coin Op Florida
Re: Nanao MS-2934s with jittery picture, bloom
« Reply #1 on: November 28, 2022, 11:26:15 AM »
A shrinking image is usually the sign in a dip in HV..

I would monitor the B+ voltage with a DMM and see if it solid or dipping.. if its solid, it maybe a sign of a soon to fail flyback.
Logged
https://www.coinopflorida.com | http://www.youtube.com/@hammysHangout | https://twitch.tv/HammysHangout

"Good engineers keep thick authoritative books on their shelf. Not for their own reference, but to throw at people who ask stupid questions. Hoping a small fragment of knowledge will osmotically transfer with each cranial impact."-eeguru

pins:  R&M, AMH, RCT, DW, DE:ST
vids: Q*bert, Mad Planets, Reactor, Sega Uni, Linked OR2SP, APB, Crystal Castle, Cloak and Dagger, MSPAC, Space Duel, Gravitar, Tempest, Omega Race, Tutankham, Warlords [custom], Tron

Offline atarijim

  • Level 5: Power User!
  • *****
  • Join Date: Jun 2008
  • Location: Seffner, Florida
  • Posts: 645
Re: Nanao MS-2934s with jittery picture, bloom
« Reply #2 on: November 29, 2022, 04:07:24 AM »
Quote from: Hamster on November 28, 2022, 11:26:15 AM
A shrinking image is usually the sign in a dip in HV..

I would monitor the B+ voltage with a DMM and see if it solid or dipping.. if its solid, it maybe a sign of a soon to fail flyback.

I second this opinion.
Logged
Pages: [1]
« previous next »