Its really dirty and the transformer is rusty.
Kirk mentioned smoke.
I did a superficial cleanbgc and took out the tubes.
The rectifier's bad.
Then before I went to recap I checked the transformer. I only checked the rectifier filament voltage, seems good.
Did the recap. One cap in the RF chassis took a bit of work, the backelite cap was easy - put Y2 caps n it. Kirk did the electrolytics.
The resistors seem ok, even the wirewound, except the divider 22, 23 and 57 - all seem to be twice the value.
Need the speaker. The speaker wires are really frayed and twisted together. I wonder if this made it smoke.
So far this is it.
Kirk
I will really need that speaker.
I could try to temporarily replace the field with a 1K wirewound resistance and use a PM but that's inconvenient.
Oh....installing those gommets at the side of the RF chassis is a real female dog.
Found two more caps I missed while changing the power resistors, changed them too.
Now I reeeeaaaaaallllly need a speaker.
The problem with replacing the field coil with a resistor is that I likely won't have a PM speaker with an output xfmr.
Hi Guys -
When should Y2 caps be used as opposed to the yellow Mallory versions?
Thanks,
Paul
Any time you put a cap across live mains power, you should use at least X-rated cap, and every time the cap crosses between the Mains and the chassis (or any touchable by user metal part) - Y-cap.
Otherwise these caps are not necessary.
So....I found two 2.2K 5W resistors which in parallel give exactly the resistance of the field coil, and with an output xfmr from Philco 90 for the 47 tube which is the same 7K as for 6F6,which is still wrong as my PM speaker is 8 ohm and philco 37-610 is probably 0.7 ohm or so.....I plugged it in and after swiching to the BC band pulled in the local station and a couple of others when holding antenna input with my hand.
Needs alignment but otherwise is ok.
This is the chassis that smoked according to Kirk. Well, the speaker wires were bare and twisted together. I wonder if this possibly could be the reason?
This is how I connected it.
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I have aligned the IF and then BC padders and trimmers.
The sensitivity increased greatly, especially after BC algnment.
The Jersey Shore station is exactly at 1160AM.
I this will be it. If Kirk has the speaker after all
Just I have restored one speaker for this same type of radio and the Voice coil (original) was 1,7ohm (I supose 2 ohm will work)
Just in case you need this info.
Good job and keep going
Jeepeto
Thanks. My goal in this particular case was to give the radio a temporary speaker, considering Kirk did not provide one - only the chassis
, to test the radio and to align it.
Which makes it not super-important as the original speaker eventually will be connected (Kirk claims he found it). Even though the impedance is several times that of what it should be, it still works just fine.
Mike.