Star wars ur

studiopaul

Member
Joined
Oct 16, 2009
Messages
405
Reaction score
3
Location
Philadelphia, Pennsylvania
Purchased a non working UR.
HV board was in a box with BU406D removed..I have replaced with a new one.


SO

Never worked on the HV circuit before so wanted to see things to be careful of.

Reading through some of the upgrades for HV for well gardner at the moment.

here are my problems and or diagnosis.

Game board swapped in another machine = works great
Amplifone Deflection swapped in another machine = works great

I have no neck glow on this machine once all assembled and powered and no clicking/ticking as I would love to hear!!

Deflection LED = ON

HV board LED = OFF

Im getting a burning smell from HV ..powered off fast!!!

on inspection the power resistor closest the heat sink in center of PCB, shows to be burning the PCB.

also no static pop when grounding monitor under the suction cup.

Where should I start the diagnosis of the board?
And what precautions should i take.

thanks
 
Do you have the new flyback transformer, or do you have the old red one? If you have the red one, then you need a flyback, at the very least....

-Ian
 
Bob Roberts has flybacks, and most of the other parts too (you'll need a new BU406D most likely).

I'd suggest reading the whole FAQ too :)


While you are working on the monitor, it would be a good idea to replace all the capacitors, as well as those horrible brown zero ohm resistors (use wire).

-Ian
 
Would like to diagnose the problem rather than replace everything..part of the learning process.
trying to follow schematic to prove whats at fault.
any way to check flyback safely without causing damage?
 
any way to check flyback safely without causing damage?

Yes. For testing the red flyback, the procedure is quite simple, and requires no special tools. First, desolder the flyback. Hold it at about eye level, pins facing down, and drop it into a metal trash can. If it makes a *clang* sound when it hits the can, it's bad.

-Ian
 
Will this test procedure work for original G07 flybacks.

Andrew

Yes. For testing the red flyback, the procedure is quite simple, and requires no special tools. First, desolder the flyback. Hold it at about eye level, pins facing down, and drop it into a metal trash can. If it makes a *clang* sound when it hits the can, it's bad.

-Ian
 
Trust what you read above. Replace the brown resistors with wire. They are bad. If not bad, they will be. Love the HV test procedure. Go with arcrevival and you will be very happy with the results.
 
The replacement HV unit was re-engineered by Mark at cinelabs.com and can be purchased through Arcade Shop for $99. The units available for less are identical (?) knock-offs.

KLOV member dezbaz has repro-ed the two special components on the HV board - the red cylinder known as the ''mystery can'' since it was called out enigmatically as MCI on the parts list, and the transformer T1. (http://www.amazingarcading.com.au/) Unlikely that they are bad unless they were cooked by the resistors.

Speaking of which, a good mod is to replace the big hot resistors with TO-220 power resistors mounted to the heat sink alongside the voltage regulators. A pdf is available detailing this mod at http://home.comcast.net/~retro-active1/pwpimages/Amplifone-HV-TO220-ResistorMod.pdf (thanks to Andre Huijts, and retroACTIVE)

If you're lucky enough to have an Amplifone, I think you should protect it by rebuilding and upgrading both boards (or sending them out). You can do it yourself as there are full procedures for troubleshooting and upgrading both the HV and deflection boards in the Amplifone FAQ produced by Michael Kelley at http://gamearchive.askey.org/Video_...tari/monitors/amplifone/amplifone_faq_1_2.pdf. Otherwise Arcrevival should be your next stop but if he is too busy I can also rebuild them.
 
Yes. For testing the red flyback, the procedure is quite simple, and requires no special tools. First, desolder the flyback. Hold it at about eye level, pins facing down, and drop it into a metal trash can. If it makes a *clang* sound when it hits the can, it's bad.

-Ian

Yea, this is the same test being used on the white knob Kxxxx flybacks. This test works all the time!
 
Thanks for the recommendations guys.
Edit: If your spot killer is on but the main board and deflection board work in another game then you have a voltage or harness issue it sounds like. Also, while I like the idea of troubleshooting the Amp, the truth is, they have so many trouble spots in their original configuration, that you really are better off just dropping a nuke on it and replacing a lot of parts or it will never end.
 
Last edited:
Purchased a non working UR.
HV board was in a box with BU406D removed..I have replaced with a new one.
SO
Never worked on the HV circuit before so wanted to see things to be careful of.

Reading through some of the upgrades for HV for well gardner at the moment.

here are my problems and or diagnosis.

Game board swapped in another machine = works great
Amplifone Deflection swapped in another machine = works great

I have no neck glow on this machine once all assembled and powered and no clicking/ticking as I would love to hear!!

Deflection LED = ON

HV board LED = OFF

Im getting a burning smell from HV ..powered off fast!!!

on inspection the power resistor closest the heat sink in center of PCB, shows to be burning the PCB.

also no static pop when grounding monitor under the suction cup.

Where should I start the diagnosis of the board?
And what precautions should i take.
thanks

HV overvolt LED is off, but no HV . . . hmmm, personally I would replace some transistors and the 4 Electrolytics on the HV. I would replace the 555 timer as well.

The 555 timer creates the pulse train which builds the HV up through the transistors and small transformer

If the Led light lights up then the problem is overvoltage, but yours never did that, it just simply never generated any HV

I would replace the parts mentioned, but also I agree to get rid of the red flyback, as they are notorious for failure.

Also check all wires soldered to board, and maybe resolder ALL of them

The reason you have no heater voltage, is the 6.1VAC is generated from a coil of wire wrapped around the flyback ferrite rod. So when there is HV there is heater voltage

If you are unable to do these things yourself, you should consider Arch Revival to repair it

All the best
 
Last edited:
Back
Top Bottom