Hantarex Polo 25 blues

mnegre

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Just like it says got the blues with this polo. New flyback, caps, and HOT, got it to work for a few minutes with neck glow then was shut down. Came back turn it on and now its ticking and no neck glow. Did the light buib test (50w) on L103 it lights up intermittently like Christmas lights on and off. Any ideas what could be wrong?
 
Just like it says got the blues with this polo. New flyback, caps, and HOT, got it to work for a few minutes with neck glow then was shut down. Came back turn it on and now its ticking and no neck glow. Did the light buib test (50w) on L103 it lights up intermittently like Christmas lights on and off. Any ideas what could be wrong?

I believe that if it lights up and stays lit, you have a deflection issue. If it blinks or goes out, the problem is on the power supply side of the chassis. If you need help, M K L is a polo guru...he can help
 
Yes, that's what I thought. I would like to give it another try before I send it to the pros. Although I been saying that for a couple of months. Any ideas what could be wrong?
 
I would follow randy fromms polo flowchart and check those components. Also double check the orientation of your caps and traces on the underside of the chassis. Removing that high voltage cage from the power supply section can be tricky, could have a hairline crack somewhere. Check for continuity with the chassis removed, across several points.
M K L gives good advise on how to go about fixing it. But polos are notorious for cracked traces...really gotta use the magnifying glass to see them
 
Thanks for the help, tomorrow I'll take some time to look at it again.
 
I would follow randy fromms polo flowchart and check those components. Also double check the orientation of your caps and traces on the underside of the chassis. Removing that high voltage cage from the power supply section can be tricky, could have a hairline crack somewhere. Check for continuity with the chassis removed, across several points.
M K L gives good advise on how to go about fixing it. But polos are notorious for cracked traces...really gotta use the magnifying glass to see them

^ all of this. :)

is it actually blowing the HOT or is it just ticking cause it can't power up? the most crack-prone areas on these are in the power section, where the cage tabs slot in, and the worst of all, the flyback. I have a chassis that spontaneously cracked under its own weight in my Killer Instinct 2 and when I had the chassis out it just looked like surface scratches across a majority of the flyback traces. it wasn't until I got the meter out to do continuity tests that I realized they weren't scratched, they were cracked apart.

that chassis still worked, but it wasn't receiving the heater voltage from the flyback, so it had no picture.
 
It's not blowing the hot. This is R103 is it ok at 11 Oma. Is this the way to check the resistance? Also got the beeping when checking on diode mode.
 

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It's not blowing the hot. This is R103 is it ok at 11 Oma. Is this the way to check the resistance? Also got the beeping when checking on diode mode.

yes measure in ohms just like your doing.
 
Why did you pull that? If it were bad the result would be the same as with a blown fuse: no life at all in the chassis.

How did you do the bulb test? With the chassis connected or disconnected from the tube?

Repeat the test with chassis disconnected from tube and on your working bench. Desolder the HOT and solder the bulb to the pads where the collector and emitter of the HOT were previously:

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Also, test the HOT with the DMM diode test. Only readings you can have with a good HOT are with the two lead combinations below (they don't have to be the same exact values as in the picture but B-E should be higher than B-C):

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So I did the bulb test like you told me, and it did stay light up so the power supply is good I suppose. Also checked the HOTs and it is good according to you instructions, I get 484 and 546. Should I change the flyback to the old one? Checked the caps and looked for cracks on chassis, what else can I do?
 
Did you also measure the B+? On US Polos it should be 138V, I think.

So you said the monitor was working for a while after replacing the flyback. It could be defective. What was wrong with the old one? Was it OEM ("Eldor" embossed on the top)?

After disconnecting the light bulb from the chassis and with power off, set the DMM to diode test and check continuity on the flyback pins. You want to have continuity (beep) across 1-3 and 5-6-9-10 but not across 1-5 (of course you don't have to desolder the flyback as in my pic). Check the old flyback the same way. Also, is pin 11 of the replacement flyback there?

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Checked the flyback and followed instructions, looks good. The HOTs good and checked the diodes according to flow chart. Here are caps 172 174 175 are they good. What is the attachment point for the the B+?
 

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The values for those caps should be:

C172 = 3.3nF
C174 = 8.2nF
C175 = 12nF

For the first and possibly also for the second you set the meter to 200pF which is too low. For the third you set it correctly to 20nF and it's good.

Set your DMM to diode test and put the leads on the tube pins shown in the pic. You want the tester to beep.

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Then set your DMM to the lowest resistance setting and check resistance across the points shown in the pic. You want to measure about 0.75ohms.

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If these tests are good, I would put the old flyback back in.
 

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Tomorrow I will continue working on it and hopefully get it working. I have cap 172 and 174 so will likely install those and the old flyback, according to instructions. Thanks for taking the time to help out.
 
Checked the flyback and followed instructions, looks good. The HOTs good and checked the diodes according to flow chart. Here are caps 172 174 175 are they good. What is the attachment point for the the B+?

Tomorrow I will continue working on it and hopefully get it working. I have cap 172 and 174 so will likely install those and the old flyback, according to instructions. Thanks for taking the time to help out.


My tip is you don't check the Box cap polys you replace them.

and you check d134 and d135 for a crack in it.

The idea is to restore the Hv P caps and E-caps

if the hot is good replace it also,

The hot can never be shorted and not kill the B+ because

it is directly tie to the same trace.

C170, C174.C172, c175.
The Hv runs to high and cause shut down.

Because of bad hv regulation, and can damage the fly and short the HOT

but not every time.

There are also high changes of open traces also but these caps

need to be replace only not checked.
 
the tests were not good, the two leads on tube did not have conductivity,no beeping, also the resistance across the two points had 1.8-2.8 @ 200 ohms (lowest setting on DDM) after doing it several times. I have not replaced c175 c170 D134 D135. Tried the old flyback and still hear a faint ticking. At what point do I check the B+ and should there be B+?
 
the tests were not good, the two leads on tube did not have conductivity,no beeping, also the resistance across the two points had 1.8-2.8 @ 200 ohms (lowest setting on DDM) after doing it several times. I have not replaced c175 c170 D134 D135. Tried the old flyback and still hear a faint ticking. At what point do I check the B+ and should there be B+?


I said check the diodes for a crack in them I didn't said just replace them.

You talking about heater pin one side is ground the other is ac heater pin.

off the flyback at about 6.3 vs ac.

you need high voltage to get voltage there.

you don't need heater to get HV

it should read on the tube about 20 ohms across the heater tube pins only.

your dc is correct you have the same dc on the collector of the HOT

if you put your meter on it you'll see.

It takes dc and a drive pulse of about 900 v P~P

with no drive at the base you will have 130v on the collector.

when in shutdown the Horix-drive ic removes the pulse

all is left is the dc on the H.O.T collector.

Need to inspect the two diodes lift one end.

confirm they are not open or shorted.

before you order the P-caps.

they do not short they open under load.

I use a ringer to test a flyback its always correct

also the o-scope as I inspect the waveform.

If it doesn't just have a hole in it..

that's how I know if the fly is good or bad.

the H.o.t gets replace because all this crap makes the H.o.t run hotter and shorten

its life. you don't want to see this chassis again.

You jumper the trace to the cement resistor you don't reflow them,

see how dark the board is that's from poor connections to the high watt resitors

around the board which have the B+ on them as they go to the horizontal circuits

like the H.O.T and Horiz-drive transformer circuits.

once parts are replaced then confirm the traces are good to the fly and ceramic resistor

for a solid repair.

Forget about the heater pins.

get the parts replaced. use your ohm meter know what the ohms is between

traces not continuity you can get a test tone from the meter with a 10 ohm resistor

you need to see zero ohms not listen for a test tone.

The ceramic resistors can get poor connection if you touch them you may see

the trace lift, if all to much of hassle then send it out

you will get a warranty with it.

or just replace the chassis , with a rebuilt chassis and get'er done right!
 
I'm all for you sticking it out and fixing it yourself. You can learn a great deal by it, and it can be rewarding. Trust me, I spent a year and a half off and on with mine, and thanks to the help I got from a bunch of klovers such as mecha, M K L, and a few others, we got it working
 
Thanks for the encouraging words, will keep working on it with the help I get here.
 
the tests were not good, the two leads on tube did not have conductivity,no beeping

It's very important that you double or triple check this because if it's confirmed that the filament is broken the tube is junk. Make sure that you put the probes exaclty on the pins that I pointed out in the picture. Touch them in various points and scratch them slightly. Check continuity (diode test/beeper) but also resistance (lowest setting). And it would help a lot if you had another tube to test with the same base connection type so you know you're doing it right.

I have not replaced c175 c170 D134 D135. Tried the old flyback and still hear a faint ticking. At what point do I check the B+ and should there be B+?

To measure the b+ you need to do the light bulb test again (HOT off circuit, bulb on C and E, caps and diodes back in). Set the meter to 200VDC and put the black probe on the heat sink around the flyback and the red probe in the points shown in the pics (one at a time):

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