Hantarex Polo 25 R255 burnout why?

JJ

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Heres what I have A friend of mine picked up a MK 1 with the polo25 pic was a little dark he was adjusting the flyback and lost the pic alltogether.. so he says brought it over for me to put a cap kit and flyback in which should be here tomorrow Thank you Bob Roberts!
but when I went to pull the board today I noticed that the R255 resistor was burnt to which I had some probably left over from my old hantarex I sold years ago..
changed it gave a rough look over didnt see anything obvious put her back in and on my test bench and no pic or neck glow, I dont remember but even with a dead flyback I should still have neck glow right ? and why or possibly what casuses the R255 resistor to blow? and why is it thats the one thats not listed on the Hantarex parts chart in the manual?
Thanks,
JJ
 
Heres what I have A friend of mine picked up a MK 1 with the polo25 pic was a little dark he was adjusting the flyback and lost the pic alltogether.. so he says brought it over for me to put a cap kit and flyback in which should be here tomorrow Thank you Bob Roberts!
but when I went to pull the board today I noticed that the R255 resistor was burnt to which I had some probably left over from my old hantarex I sold years ago..
changed it gave a rough look over didnt see anything obvious put her back in and on my test bench and no pic or neck glow, I dont remember but even with a dead flyback I should still have neck glow right ? and why or possibly what casuses the R255 resistor to blow? and why is it thats the one thats not listed on the Hantarex parts chart in the manual?
Thanks,
JJ

It should measure around 150 a flame Proof resistor, it runs hot

What parts have you check?
Hot maybe shorted,replace with upgraded transistor .

Your filament voltage is ac,it comes from the fly only,to the top two pins on Neck Bd.
I assume you tryed to turnup the G2 Pot
do you still get SMPS voltages?

Check some more circuits.
Let us know what you find..
 
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It should measure around 150 a flame Proof resistor, it runs hot

What parts have you check?
Hot maybe shorted,replace with upgraded transistor .

Your filament voltage is ac,it comes from the fly only,to the top two pins on Neck Bd.
I assume you tryed to turnup the G2 Pot
do you still got SMPS voltages?

Check some more circuits.
Let us know what you find..
it's off the tube and on the bench now but just checked continunity on the T114 and appears good, I did not try the G2 and what is SMPS?
I'm still pretty green at alot of this, simple stuff fine, goota learn more though!
 
it's off the tube and on the bench now but just checked continunity on the T114 and appears good, I did not try the G2 and what is SMPS?
I'm still pretty green at alot of this, simple stuff fine, goota learn more though!

SMPS is "switching mode power supply", basically the power supply section of the monitor underneath the cage. :)

it's what makes the Polo not require an isolation transformer.

good luck to you sir, you have balls working on a Polo!
 
SMPS is "switching mode power supply", basically the power supply section of the monitor underneath the cage. :)

it's what makes the Polo not require an isolation transformer.

good luck to you sir, you have balls working on a Polo!
Yeah I guess or like Diego at arcadepcbs said maybe I've just been schocked so many times by them I've developed an attraction.
also could just be to dumb to know better..
out of the 7 I've had each one had a different issue, this one appears to be combining them all..
 
It should measure around 150 a flame Proof resistor, it runs hot

What parts have you check?
Hot maybe shorted,replace with upgraded transistor .

Your filament voltage is ac,it comes from the fly only,to the top two pins on Neck Bd.
I assume you tryed to turnup the G2 Pot
do you still get SMPS voltages?

Check some more circuits.
Let us know what you find..
I've got 77.8v at the neck board
120at the fuse
123 at T101
same with t114


ok that was all done grounded on the neutral line ..
on chassis ground I get nothing at the necboard nothing from t114 45 at t101
when I checked resistance at t114 the center pin was nothing but I get continunity at between 1 and 3 which was the same on the working polo25 I have.
 
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I've got 77.8v at the neck board
120at the fuse
123 at T101
same with t114


ok that was all done grounded on the neutral line ..
on chassis ground I get nothing at the necboard nothing from t114 45 at t101
when I checked resistance at t114 the center pin was nothing but I get continunity at between 1 and 3 which was the same on the working polo25 I have.


Before I start troubleshooting the chassis
I replace all the caps and Polypropylene caps and HOT and fly
Fresh solder to Large heatsink parts and large watt reisitors
and replace vertical ic,then i check to see if it has a problem
from there.
Sorry if thats not what you want to hear!
Check Mouser Etc for Parts.
I'm sure everybody just replace the electrolytic's and maybe the HOT
and Fly but it needs more,the Polypropylene caps dry up too.
Thats why the chassis, don't last..after repair within a day or two.
Get all the parts in first then see what its doing.
The parts List is longer in some case's,lets hope we don't have to go there..
Good Luck!
 

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Before I start troubleshooting the chassis
I replace all the caps and Polypropylene caps and HOT and fly
Fresh solder to Large heatsink parts and large watt reisitors
and replace vertical ic,then i check to see if it has a problem
from there.
Sorry if thats not what you want to hear!
Check Mouser Etc for Parts.
I'm sure everybody just replace the electrolytic's and maybe the HOT
and Fly but it needs more,the Polypropylene caps dry up too.
Thats why the chassis, don't last..after repair within a day or two.
Get all the parts in first then see what its doing.
The parts List is longer in some case's,lets hope we don't have to go there..
Good Luck!
It's never what ou want to hear but I agree with you, at this point I'm just considering wether it's actually worth it or not. I have several WG7100 boards that are good and even a ducksan that needs a new Hot that I think would be better, not to mention the time and money. I should just mod his cab and put in one of the 2 extra 27" neotec monitors I'm planning to sell and be done with it. basing all this on the Hantarex's reputation..
 
Well got tired of jerking around with this board and grabed the working polo25 put the new flyback and cap kit on it...... got about 10mins of play time then nothing.. same as the other one. and this one played fine before colors were just a bit off..

Last year I hit up Diego about another 20" polo to match the one I had which has such an awesome picture on the Naomi playing Spawn, he suggested I sell it and put the money into fixing my wg7400 I'd be way better off. he hates them and I'm starting to understand why..
 
changed the regulator, and the hot rechecked everything turned it on and within about 20seconds there was a couple spark that I didnt see where they came from and nothing back to square one and another wasted hot! put in another hot plugged her back in and nothing. been checking continunity and so far I'm at a loss other than R255 (the resistor right up fron that always burns) goes right to ground on one end, the schematic says it's supposed to go to a w103 that I cant find? and I've already got a splitting headach from this damn thing and I'm tired of getting schocked all to hell from it. never had a board hold so much juice for so long..
 
I'm working on a 33" Polo currently. I don't know if it's much help but, I have the same R255 resistor burnt out. I've also notice a few other components burnt as well. I don't know if they have anything to do with it or not but, here's a list of what I've replaced so far:
R255 (150ohm flameproof)
R167 (2.7ohn flameproof)
L101 (still need a part # for this one!!! it was def. burnt though)
D106 (BA159)

my monitor had vertical collapse so I also replaced:
IC103 TDA1675
IC104 TDA2593
capkit

Don't know if that helps or not but, if you haven't checked near L101 it might be worth a check since it seems we have the same resistor burnt. Like I said, hope this helps! And hey, if you could sneak a peak at your part # for L101 I would greatly appreciate it!!!! :)
 
If you keep burning a flame proof resistor out, the easiest solution to find the problem is to unhook everything after that resistor and see if the resistor survives. if it does, start adding each component back into circuit 1 by after after the resistor. Its probably not what you want to hear, but its the only way I know to reliably find the problem if its not any of the obvious / common problems.
 
I'm working on a 33" Polo currently. I don't know if it's much help but, I have the same R255 resistor burnt out. I've also notice a few other components burnt as well. I don't know if they have anything to do with it or not but, here's a list of what I've replaced so far:
R255 (150ohm flameproof)
R167 (2.7ohn flameproof)
L101 (still need a part # for this one!!! it was def. burnt though)
D106 (BA159)

my monitor had vertical collapse so I also replaced:
IC103 TDA1675
IC104 TDA2593
capkit

Don't know if that helps or not but, if you haven't checked near L101 it might be worth a check since it seems we have the same resistor burnt. Like I said, hope this helps! And hey, if you could sneak a peak at your part # for L101 I would greatly appreciate it!!!! :)

L101 a 33uh coil is it open?
How are you getting secondary voltages from smps with it open?

The tda1765 due fail.
R167 is supply voltage to the vertical ic if ic shorts it will open..
The R255 maybe running hot because of a leaky t119 Bc547b or d142..
the red jumper on top of board is w103 to w102 which leads to ground.
r255 is not changing its resistance that i have notice whats yours read?
If it is check t119 and d142..
 
Sorry for the confusion. My L101 is still working apparently because I do still have secondary voltages it's just in bad shape so I wanted to replace it. Someone has worked on this board previously and burnt some stuff up pretty bad.
Anyway, i'll take a look at some of the items you mentioned tonight and see what I come up with and post back later this evening. Send me a pm if you dont hear back.
 
lost in the message

I also have a burnt R255. Im trying to replace it but it is burnt beyond recognition. There are several threads mentioning 150 ohms, 180 ohms, and a few others. What should this resistor actually be? I cant find it specifally anywhere and as stated before, it does not appear to be on the schematic.

greg
 
Whats Yours measure? How's the picture look??

Its because the flyback and HV circuits were bad and over heating the

resistor after restoring the HV circuits the resistor should be Ok

Its not burning up, its just running hot over time and looks bad.
 
value of R255

The picture had all the signs of bad caps. Did a cap Kit and then figured I would go ahead and replace the resistor. (I only have the chassie right now, the tube is on location so I cant see what it look like.) If it was good before, its bad now. When I unsoldered one leg to measure it, it broke in half. I assume it would not hurt to put a slightly higher wattage in there. But still need the value so I can replace it.

greghig
 
The picture had all the signs of bad caps. Did a cap Kit and then figured I would go ahead and replace the resistor. (I only have the chassie right now, the tube is on location so I cant see what it look like.) If it was good before, its bad now. When I unsoldered one leg to measure it, it broke in half. I assume it would not hurt to put a slightly higher wattage in there. But still need the value so I can replace it.

greghig



I found it to be 150 ohms you can up the wattage .5

and send it out an hold off for the others untill they fail..

or replace what was there after you restore the HV circuit.

If you replace it and it doesn't smoke, just runs warm then

leave it alone and check your picture brightness level.

for a good stable image.for any issues after you install it.

Not a good reliable chassis .It Has a good picture

when it works.

I'm always open to new failed parts if it burns up check that zener

its tied to near it.
 
So I did a cap kit on a Polo and it looked beautiful after! While putting in the remote board up front I dropped it and the back of the pcb touched a piece of metal and boom whole thing went out. I looked at the adjustment board and it looked fine. I noticed the R255 was burnt completely up after that happened.

Replaced R255 and still nothing. The thing is completely dead. Any advice? Could it have taken the HOT with it?

Thanks!
 
So I did a cap kit on a Polo and it looked beautiful after! While putting in the remote board up front I dropped it and the back of the pcb touched a piece of metal and boom whole thing went out. I looked at the adjustment board and it looked fine. I noticed the R255 was burnt completely up after that happened.

Replaced R255 and still nothing. The thing is completely dead. Any advice? Could it have taken the HOT with it?

Thanks!

I did this before. Don't remember how I solved it though
 
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