After reading all of the replies I am wishing I had stepped in sooner, as I think I could have saved you a lot of grief. When you said that their was a pin missing from the flyback I knew it was folded underneath because they usually ship that way. Based on the symptoms you were having I think it would have worked if that pin was correctly placed. It sounds like you have additional problems now, which I will try to help you with. First thing, in the future always replace the HOT with the flyback even if it tests good. In the past I have tried replacing just the flyback and end up with a shorted hot and sometimes other shorted components a month or so later.
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This cage needs to be removed if ever you go to repair this chassis, these are the steps for removing it: Step 1: Unscrew the cage.
This may use a little bit of finesse to get off, but it just pulls off. The bracket has small tabs that go into clips on the top of the chassis. The chassis I used for this demonstration actually had the clips bent sideways, so it was tricky to get out. Once you get it out though, it might be a good time to straighten the tabs with needlenose pliers.
Step 3: Remove the power supply cage. The cage has tabs that stick through holes in the chassis and are rotated to lock the cage on. Sometimes the tabs have bends in them, if you grab them with needlenose pliers like this it can flatten them out, and twist to straighten them.
The cage should come right off then. You will have free access now to replace the capacitors and do whatever else you like. The power supply section: As I noted, the wall heatsink has the voltage regulator mounted to it.
There are two large diodes near the filter capacitors, these are the rectifier diodes. After a lot of hunting around it was revealed that the solder pads to the larger transformer cracked off; about 8 jumpers later, the monitor powered up again. There are two ceramic resistors, these are prone to the solder joints cracking — or in the case of the transformer chassis, an entire chunk of the PCB broke off underneath. So I had to get really fancy with patching those back together.
The flyback transformer: If ever the flyback fails, conventional wisdom in KLOV lore dictates that the HOT horizontal output transistor will go with it. There have been some parts suppliers that have been circulating bad units, notably Bob Roberts. Do not ever replace a flyback unless it is definitively dead. All the other stuff: This is where all the real action is at.
Starting with the middle heatsink, there are two ICs: the larger multi-legged one is the vertical deflection IC; the smaller is for horizontal width control. Directly next to the smaller transistor is the width coil; under no circumstance should you ever adjust this, as the width control is fully electronic. To its right is a transistor mounted on the outer heatsink wall; this is the horizontal output transistor HOT , part number BUA.
There are two types of neck sockets: the one pictured, and another one that the entire plastic part of the socket lifts off and is very difficult to open. To the right of the neck socket in the picture are three transistors: these are the drive transistors for the primary colors Red, Green, and Blue. With the parts removed now is a good time to inspect the PCB for cracks. From the component side, you may visually see cracks like in the bottom picture.
On the outer edge of the chassis behind the HOT heatsink are two ceramic resistors. The solder pads will typically break off from the traces. In the past I tried to lay new wire over the existing traces, but now I just run 18 gauge wire between points. Hantarex Polo tips and tricks: Vertical Linearity: Common problem with Polos is the top and bottom of the picture are not even heights.
Sometimes the top will be stretched, and the bottom squished, and vice versa. Pictured below stolen from another KLOV user is what it looks like. High voltage shutdown: Do you hear a pulsing ticking sound? The part is Philips BUA. Another place to check is the flyback, inspect for cracks. If the flyback is bad you will have to replace it.
Another spot to check is R You want this to be within V DC; is it too high or too low? The adjustment is labeled as V. Turn it very slowly until you reach V. This process of course assumes that you have a working monitor with functional horizontal deflection. Blooming: Ever notice a transition between a dark screen to a bright white one and the whole picture expands and contracts?
As noted above, these seem to fail a lot, probably from the increased ambient heat from the cage being installed. Yoke: The Polo has a unique connector for the deflection yoke.
This black jumper wire is a very handy feature, as it will prevent the monitor from powering on with the yoke unplugged running any monitor with the yoke connections not plugged in can potentially damage the chassis. So after tinkering with it enough, I reproduced the same problem on another chassis and figured out that it was that one lone pin that caused the problem.
Desolder the transistors out first, use a pair of needlenose pliers to flatten and straighten the transistor legs. If you have a fiberglass brush or a pick you can really get the goo off. Squeaky clean.
Before reinstalling the transistors, use a piece of sandpaper to sand the tips of the heatsinks. The following 90 degree method is an optional step, permitting you want the transistors to never move. Then bend the legs flat 90 degrees like pictured. This particular one had high voltage, but no heater glow. It was very confusing cause I checked the neckboard over about times and found nothing wrong with the neck socket or R You can see plain as day how many cracks there were in the flyback area.
Underneath you can see that I had to patch about 7 traces. Update: I wound up having to fix all of this again, now I think every flyback trace is jumpered. Something else unusual happened to this chassis. The outer frame trim is held together with screws running through the PCB. It developed a huge crack where the metal frame border screws the deflection board in.
I will include new intel when I get it.
Hantarex Polo 25"/27"/33" Series Flyback Transformer
1242-5001 Hantarex Polo Flyback