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Old 24th Jan 2011, 5:05 pm   #81
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Default Re: Philips B3X85U troubleshooting

TRANSFORMER (Four Tag side)

Meter on ohms range. Connect one lead to ANY one of the four tags. Connect the other lead to each of the other tags in turn. You should have continuity in every case. By continuity I mean that the meter drops from infinite reading to something lower when you touch the second lead on the tags. One tag is broken or the wire has come off it, but there's still part of it remaining on the transformer. Test to that, not to the diconnected lead and capacitor.

SPEAKER

Make sure that at least one tag of the speaker has no wires attached. One lead of the metar on each tag. The reading should drop from infinity to something like 5 ohms.
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Old 24th Jan 2011, 5:22 pm   #82
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Default Re: Philips B3X85U troubleshooting

On the drawing that I'm sending, I understand that there should be continuity between all three yellow tags.

Aside from this, there should be continuity between all four red tags.
Am I right?
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Old 24th Jan 2011, 5:25 pm   #83
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Default Re: Philips B3X85U troubleshooting

What I usually do to test continuity, is place the meter where it wil beep or buzz. Is that alright?
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Old 24th Jan 2011, 5:33 pm   #84
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Default Re: Philips B3X85U troubleshooting

Quote:
Originally Posted by Abraham
On the drawing that I'm sending, I understand that there should be continuity between all three yellow tags.

Aside from this, there should be continuity between all four red tags.
Am I right?
Yes. When testing on the secondary (three tag side) make sure that the speaker is disconnected or you'll get a false reading.

Quote:
Originally Posted by Abraham
What I usually do to test continuity, is place the meter where it wil beep or buzz. Is that alright?
It's better to read the meter display so you can tell exactly what the resistance of the windings is.
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Old 24th Jan 2011, 5:36 pm   #85
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Default Re: Philips B3X85U troubleshooting

Yes the full primary and secondary needs continuity to function. One of your earlier photos seems to show the link between the inner two tags broken, this needs to be checked and put right. Remember these tags don't like being repeatedly soldered and unsoldered. A buzzer will only work with low resistances and is better kept for buzzing out wiring. As Graham has said, it is better to use the meter and on the correct range or autorange.
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Old 24th Jan 2011, 5:38 pm   #86
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Default Re: Philips B3X85U troubleshooting

Ok then, on the four tagged side, That first tag does not have continuity between the other three.

Now I'll check it as you mention with the meter on ohms. Do I have to turn on the radio?
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Old 24th Jan 2011, 5:40 pm   #87
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Default Re: Philips B3X85U troubleshooting

If you find full continuity as expected put all the wires back on as per the chassis layout. Then take voltage readings from chassis to each of the tags on the primary. Every tag should show a voltage.
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Old 24th Jan 2011, 5:40 pm   #88
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Default Re: Philips B3X85U troubleshooting

The link beween the two inner tags is not broken as it looks.
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Old 24th Jan 2011, 5:44 pm   #89
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Default Re: Philips B3X85U troubleshooting

Quote:
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Now I'll check it as you mention with the meter on ohms. Do I have to turn on the radio?
NO, NO NO. Resistance readings are always taken with power OFF.
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Old 24th Jan 2011, 5:45 pm   #90
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Default Re: Philips B3X85U troubleshooting

Whenever checking continuity on the Ohms range the circuit must not have power on it. Turn it off double check that you have before proceeding. Please read the repair section on this site to gain knowledge of such things.
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Old 24th Jan 2011, 5:48 pm   #91
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Post Re: Philips B3X85U troubleshooting

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Originally Posted by Abraham View Post
Ok then, on the four tagged side, That first tag does not have continuity between the other three.
If this tag does not have a reading between it and the others then this is where the fault must be, check the wire going to the tag.
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Old 24th Jan 2011, 5:51 pm   #92
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Default Re: Philips B3X85U troubleshooting

Quote:
Originally Posted by geofy View Post
Whenever checking continuity on the Ohms range the circuit must not have power on it. Turn it off double check that you have before proceeding. Please read the repair section on this site to gain knowledge of such things.
AND wait a couple of minutes before taking resistance measurements to let the voltages on the capacitors die down.
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Old 24th Jan 2011, 5:52 pm   #93
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Default Re: Philips B3X85U troubleshooting

geofy.

If Abraham has been using the buzzer in his meter as a continuity tester it's possible the transformer is OK, as continuity buzzers require quite a low resistance to operate. The transformer was OK a couple of days back, as there was HT on the output valve. If the winding has been broken as a result of the tag breaking off it'll be well worth trying to dig out the end.
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Old 24th Jan 2011, 6:02 pm   #94
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Default Re: Philips B3X85U troubleshooting

Ok, I took the reading with the meter on ohms. The it is just as you said. The meter drops from infinity to 000 on all tags except the first tag when I touched the wire underneath. When the cap was touched, the meter did not drop.

Other than that, on the speaker, I disconnected one of the wires on the speaker itself and touched both tags with the meter that go to the speakers, and I got a reading of 1.1ohm.
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Old 24th Jan 2011, 6:05 pm   #95
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Post Re: Philips B3X85U troubleshooting

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geofy.

If Abraham has been using the buzzer ...dig out the end.
Yes Graham, the buzzer shouldn't be used for this, especially on the primary. It really shouldn't be taking this long to sort this out
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Old 24th Jan 2011, 6:10 pm   #96
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Default Re: Philips B3X85U troubleshooting

Quote:
Originally Posted by Abraham
Ok, I took the reading with the meter on ohms. The it is just as you said. The meter drops from infinity to 000 on all tags except the first tag when I touched the wire underneath. When the cap was touched, the meter did not drop.
OK. The transformer is faulty, but all is not lost. Carefully remove the insulation material from around the broken tag. With any luck you'll find the disconnected end of the winding. Scrape any insulation off it and solder it back to the tag. Then check the resistance again.

There's no need to check continuity to the capacitor. I will obviously show open circuit with a disconnected wire and winding.
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Old 24th Jan 2011, 6:11 pm   #97
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Default Re: Philips B3X85U troubleshooting

Readings from lead on fourth tag and third tag measured 13.4 ohm. Fourth and second tag measured 13.4 ohm. Fourth and first tag measured infinity. and Second and Third tag measured 0.3 ohm. Third and First tag measured infinity. Second and First tag measured infinity.
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Old 24th Jan 2011, 6:19 pm   #98
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Default Re: Philips B3X85U troubleshooting

Should I take the transformer off the chassis to work on it?

Last edited by Abraham; 24th Jan 2011 at 6:20 pm. Reason: clear up question
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Old 24th Jan 2011, 6:26 pm   #99
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Default Re: Philips B3X85U troubleshooting

That would probably be easiest, but be careful not to break off any more tags.
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Old 24th Jan 2011, 6:33 pm   #100
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Default Re: Philips B3X85U troubleshooting

Alright then, I'll report as soon as I have that fixed.
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