Qnic horizontal coil

hine62

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I'm looking into buy a horizontal coil for my qnic cgn-2500 chassis. Turning the coil produces no change in width. I was able to pull the core out without a problem.

According to the diagram it has three connection points on the board. Where would be the best place to get one?
 
Its not the problem if it has any kind of continuity.

The width cap is the suspect and likely bad part.

The polyester cap off the yoke to ground.

Get the manual and find location on the schematic or look

for the cap under 600v's in the High voltage area.

and get the value of it.
 
Thanks Ohmerone!

I found C706 (0.39uF 400V) and C716 (0.01uF 630V). C716 comes directly off of a post of the horizontal coil then to ground on the pcb. I'm going to replace both of these, but the ones close by look like they need to be replaced also.

 
Either check shorted?

extreme change in the value means its bad too.

most DMM has cap checker. but replace it anyway.

This chassis used different tube.

If the chassis seems to be the correct chassis for the tube and yoke.

then replace the same values you find in the circuit.

Not all HV caps need to be replaced.
 
No change in width after cap replacement. I also replaced two transistors in the width line, but that did not produce much change.

I am able to change the width with the coil now, but not much. Maybe 1/4 inch in at most. The pot on the control board is turned all the way down.

The core of the coil does slide all the way down to the bottom. Shouldn't the coil stay in place after adjustment? I did notice that the farther down the core is the width narrows. Is the core magnetic?

Can i buy a new core? Or should i replace it?
 
the width coil is only designed to change the width by 1/4" to 1/2".
 
the width coil is only designed to change the width by 1/4" to 1/2".

That makes sense. My coil core doesn't stay in place after adjustment. Is there a replacement? I've seen other models but not Qnic CGM-2500s. Also there are two caps 0.01uf 1.6kv and 0.0022uf 1.6kv that are hard to find. I think they might be the problem, since I'm getting get some adjustment now.
 
That makes sense. My coil core doesn't stay in place after adjustment. Is there a replacement? I've seen other models but not Qnic CGM-2500s. Also there are two caps 0.01uf 1.6kv and 0.0022uf 1.6kv that are hard to find. I think they might be the problem, since I'm getting get some adjustment now.


we stock the .01uf
https://www.arcadepartsandrepair.com/store/monitors/01uf-2000v-metalized-film-capacitor-3-tolerance/

the only one in .0022uf we stock is a ceramic disc so i am not sure your tolerance and type you need.
https://www.arcadepartsandrepair.co...00v-ceramic-disc-capacitor-heavy-duty-mc1047/


i have seen a strip of what looks like teflon tape running through the inside of the width coil and maybe your missing that if the slug is loose or its the wrong slug.
 
What game are you using on the chassis.

and is it on a 25" tube?

Is the image to wide or to narrow?

Got a photo of the image. check game test patterns

when adjusting geometry.

you can add a little tape to the edge and screw it down to where it was

when you started.

I would not suspect the High voltage safety caps.

How the B+ measure?
 
What game are you using on the chassis.

and is it on a 25" tube?

Is the image to wide or to narrow?

Got a photo of the image. check game test patterns

when adjusting geometry.

you can add a little tape to the edge and screw it down to where it was

when you started.

I would not suspect the High voltage safety caps.

How the B+ measure?

The image is to wide.

The tube is a 25" in a NeoGeo 4 slot cab.

Here is a pic of the test screen:


I have not checked the B+, but have done some research on it. Where is it located on the chassis?
 
Need to bring it in and center the image.

On your test pattern how many square's from left to right should you have?

is there a jumper next to the polys for raster shift left or right or

is it a wide or narrow jumper?

Next to the polys.

have you tryed that?

and there's horiz-size pot on rem board and there's a pin pot on pin board

the test point is a 20 watt resistor.

one side is input to regulator and other side is regulated B+

If a little high just replace it.

If 129.9dc vs then leave it in.

Heres some thing to check.
 
Need to bring it in and center the image.

On your test pattern how many square's from left to right should you have?

is there a jumper next to the polys for raster shift left or right or

is it a wide or narrow jumper?

Next to the polys.

have you tryed that?

and there's horiz-size pot on rem board and there's a pin pot on pin board

the test point is a 20 watt resistor.

one side is input to regulator and other side is regulated B+

If a little high just replace it.

If 129.9dc vs then leave it in.

Heres some thing to check.

Thanks again for all you help. I should note that I have done a cap kit already.

There should be 19 squares across from left to right, so the image is too wide. I have the image centered, but one square is cut off on each side. There is no jumper for width, the only adjustments are the coil and the pot on the remote board. The pot only reduces the width slightly. About half way through the pot adjustment there is no effect on the width. Could the pot be bad?

Here is a pic of the 20w resistor, is the arrow where I should check the dc voltage?

 
No but. You can remove the pot and measure the ohms as you slowly rotate the pot.

The test point is at the other end of the resistor or on the bottom of board.

Another test point is the r710 3 watt resistor going into the Horizontal transformer its up by

the horiz-pot one side is the B+ and the other is 12vs.

c909 is in the schematic and parts list, but I don't see on the main board.

need to find it .its a BP/NP cap if someone put a polarized in there that could be an issue

another is if Q705 collector is low ohms to ground

and it should have a insulator between the collector and heatsink.
 
Just tested both sides of the r710. The right side was 87.2 and the left side (next to the metal fin) was 181.6. Looks like it's too low or too high? My multimeter was on 200v dc.

Also the capacitor in 799 was the one for 909? I did put in a cap for 799, but that didn't help. The cap for 799 must be 4.7uf 50v bp. c799 is on the board pic, but not in the board schematic. The reverse is true for c909, in the schematic but not on the board. Interesting... Maybe it is a typo.
 
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This maybe your problem.

double check another TP.

The regulator is a str30130

get the datasheet via google str30130

it with show the pin config so you can test the output of the regulator

or measure at the other side of the 20watt resistor.

easy to get to from the bottom of chassis but not that easy from the top.

just to make sure test the voltage at the regulator.
 
I soldered a wire to the other side other the resistor on the bottom of the board. It measured 160. Looks like I need to replace it. I wondering where I can get one from? (180 5% 20W cerment resistor)
 
You need to check for bad connections to the regulator

if good then replace the regulator

the resistor's are good.

Then test the voltage again.
 
After testing line in and out of r999 I cleaned up some solder joints and the b+ is a steady 128.6 now. Not sure what to check next....

Update: After reflowing over half of the board and replacing c799 with a 63v, there is more adjustment in width. I wondering if this chassis was connected up to a 26" monitor, maybe it would be fine.
 
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Ok, the b+ is good.

Now does this chassis have a E/W board, and is it detachable or soldered in?

can you get the width in by removing the E/W board?

Any monitor over 25" then it needs the E/W board
 
There is no e\w board with my chassis. I did see it in the manual.

Edit: On the schematic page in the manual my RCA monitor is listed as a 26"? I'll take a better look tonight, but I believe the monitor tag says 25".
 
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