Philips B3X85U troubleshooting

[Station X]

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.

[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?

[Abraham]

What I usually do to test continuity, is place the meter where it wil beep or buzz. Is that alright?

[Station X]

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.

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.

[geofy]

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.

[Abraham]

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?

[Station X]

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.

[Abraham]

The link beween the two inner tags is not broken as it looks.

[Station X]

Originally Posted by Abraham

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.

[geofy]

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.

[geofy]

Originally Posted by Abraham

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.

[dennishoy]

Originally Posted by geofy

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.

[Station X]

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.

[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.

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.

[geofy]

Originally Posted by Station X

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

[Station X]

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.

[Abraham]

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.

[Abraham]

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

[Station X]

That would probably be easiest, but be careful not to break off any more tags.

[Abraham]

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