Help with identifying monitor chassis.

[holaplaneta]

Hi there, I got an old Dynamo HS-5 cab that could definitively use some new caps. The monitor is a Zenith ga63adg25x, but I honestly this is my first cab and canīt recognize or find the chassis model.

I already surveyed this great page that the real Bob Roberts gave me but Iīm honestly clueless... 

http://www.therealbobroberts.net/monitor.html

If you could help me, I would really appreciate it. 

Thanks!

[MonMotha]

That looks like a Kortek clone of a Wells k7000 series.

Also note that your big AC smoothing cap is bulging from the looks of the pictures.  This happens on these things, but it isn't included in most "cap kits", so be sure to get one.  This causes all sorts of fun problems as it puts ripple on B+.

[holaplaneta]

Thank you so much! Go wonder I got a clone.

So should I get a cap kit for the equivalent of a WG K7000 series monitor then?

[MonMotha]

Yep.  IIRC, even the designators are the same, but check before you go installing based only on the list that may come with the kit.  Make sure you're putting things in the right place, of course.

Like I said, you also appear to need the big cap in the corner.  It's not included in most cap kits, so make sure you pick one of those up, too.

[holaplaneta]

Great help, thank you so much, Iīll make sure to get the extra cap and try not to blow it up installing them. 

[holaplaneta]

Update:

I shot an email to real bob and he said that:

"It does look like another K7000 rip-off, but that doesnt mean it uses the
same caps & it definitely doesn't use a K7000 flyback.

You could get a K7000 cap kit & cross your fingers. The flyback you might
get lucky with by pulling it & getting the actual PN off from it to try &
track down. As for the filter the K7000 uses a 560uf200v for you to xref it."

So now I need to desolder the flyback in order to know which model it is and track it down, and if I order the cap kit for the WG K7000 it might be useless... damn.

I wish this could be easier. I canīt believe that I got a monitor chassis which model is not anywhere on the web. 

Thanks for the help!

[mgb]

As far as the caps go, why not just read the number on each cap and then cross reference that against known cap lists.
Each cap will have a number stating the mF and voltage (eg. 4700 mF @ 50 V)

I believe there is a stickied cap kit list in the monitor section otherwise I'm sure Bob Roberts would be able to determine which kit to get.

[PL1]

Be sure to match all markings/ratings.

Took a while to find caps that were the right uF/mF value, voltage, size (height and diameter), lead spacing, and rated for 105 degrees C to fix an LCD monitor, but it's been working fine for several years now.


Scott

[MonMotha]

I have used a k7000 kit (from Bob, no less) on this exact chassis (from a Neo-Geo).  IIRC even the designators are the same as the WG model.  Bob does not include the big cap on the rectifier output, so make sure you get that.  They do go bad; in fact it was the primary fault on the unit I'm drawing this experience from.

Unlikely you need a new flyback unless you have reason to suspect it specifically (e.g. arcing).

[holaplaneta]

Thanks for all your help. This post is for future visual reference.

Today finally I had the chance to take some more pictures. I got one label from the flyback that reads:

ETF46L25AY

1N1 11.7

and other two pics of the bulged AC cap showing itīs specs and "23V6M" at the top.

Iīll mail them to real bob to get any comments and recommendations.

I already ordered the WG7000 cap kit but I still need the big AC one.

[mgb]

that large filter cap definitely needs to be replaced.

it is a 680 micro farad, 200 volts

most caps I see list it as volts rather than wv which from what I understand means working volts

if you go to the capacitor section of bob roberts site and do a find for 680, you will see a 680uf200volt B+ filter for 4 bucks

[holaplaneta]

Thanks for the help. That info is really great.

I just found out about the Universal Replacement Arcade Monitor chassis 25" CRT Zoom, could I just get one of this and replace my chassis and problem solved?

http://www.dirtcheaptrading.com/index.php?page=shop.product_details&flypage=flypage.tpl&product_id=68&category_id=12&redirected=1&option=com_virtuemart&Itemid=16

Info
This chassis will work for 25"-29" Monitors. New Wei Ya Replacement chassis. This chassis is for standard resolution CRT CGA only...if your monitor was another resolution, it will now be standard. This chassis will not replace all, but it will replace most. To determine if it will work on your monitor please follow these instructions.

You must find a CRT with these specifications:

1) Measure the vertical ohms, it should be 6 ohms to 12 ohms, usually the yellow and green wires coming from the Yoke. If yours is not between 6-12 ohm this chassis will not work!
2) Measure the horizontal ohms, it should measure over 1.5 ohms. If not you can take a 5 to 10 watt 1 ohms resistor and add it in series to the circuit to increase the ohms to get it over 1.5.

[MonMotha]

You could potentially do that.  You'd have to check yoke compatibility as described.

Fixing the monitor you've already got is probably cheaper and maybe even easier.

When you go to replace that cap, you'll want to measure the lead spacing on it.  Caps that big are the "snap in" type, so you can't bend the leads to make them fit.  Hence, you'll have to ensure your replacement is both electrically AND mechanically compatible.  Compatible replacements seem to be readily available (I just did this on this exact model about 6-8 months ago).

[mgb]

What exactly is the problem with the existing monitor? besides the buldged filter cap.
 I don't believe you ever gave that info but forgive me if i missed it.

If its just kinda dull colors than it seems it would just be cheaper and easier to do the cap kit on the existing chassis
if it shuts down on you periodically, then just reflowing all the solder joints while doing the cap kit may fix that problem.