i recently purchased two pc board mount I.F transformers. They are 455kc. I cant figure out the pin layout (plate,grid etc.) can anyone help? I don't even know if they will work for the AA5 radio I am trying to rebuild. I am almost finished with construction of the radio. I would like to use the old I.F transformers but they are probably way out of alignment(i was playing around with the screws to get the old radio to work) and im afraid they won't work. I dont have a RF generator. Can anyone help????

Hi, Gary. Those PC-mount xfmrs are probably for transistor radios and not very suitable for high-voltage tube-type sets.

Just because you "played around" with the adjustments of the original IF xfmrs doesn't mean they are bad or unusable. Just check primariy and secondary sides with an ohmmeter to make sure the windings aren't open. If not, the xfmrs are OK.

Set the original IF xfmrs' screw adjusments to their midpoint and align by ear. You'd be in the same boat, only worse, if you used the transistor-set IF xfmrs.

Doug

:i recently purchased two pc board mount I.F transformers. They are 455kc. I cant figure out the pin layout (plate,grid etc.) can anyone help? I don't even know if they will work for the AA5 radio I am trying to rebuild. I am almost finished with construction of the radio. I would like to use the old I.F transformers but they are probably way out of alignment(i was playing around with the screws to get the old radio to work) and im afraid they won't work. I dont have a RF generator. Can anyone help????

Gary,

Some IF manufacturers marked the grid/diode (secondary winding) connection with a paint dot. You can use a multimeter to find the other connection.

Radiodoc

:Hi, Gary. Those PC-mount xfmrs are probably for transistor radios and not very suitable for high-voltage tube-type sets.
:
:Just because you "played around" with the adjustments of the original IF xfmrs doesn't mean they are bad or unusable. Just check primariy and secondary sides with an ohmmeter to make sure the windings aren't open. If not, the xfmrs are OK.
:
:Set the original IF xfmrs' screw adjusments to their midpoint and align by ear. You'd be in the same boat, only worse, if you used the transistor-set IF xfmrs.
:
:Doug
:
::i recently purchased two pc board mount I.F transformers. They are 455kc. I cant figure out the pin layout (plate,grid etc.) can anyone help? I don't even know if they will work for the AA5 radio I am trying to rebuild. I am almost finished with construction of the radio. I would like to use the old I.F transformers but they are probably way out of alignment(i was playing around with the screws to get the old radio to work) and im afraid they won't work. I dont have a RF generator. Can anyone help????

Norm knows how to align by ear for perfect station spacing. I do, too, but I forgot how, since I usually use a generator now. I believe that I fix the low end with the IF transformers, and the high end with the oscillator trimmer. If your radio has an oscillator padder (series trimmer), things can get ugly. Do not lose hope, though. When you turn the screws too far, you don't ruin the transformer. You just need someone else to help you re-tune it, if you can't do it yourself.

I think that Peter, or someone else, came up with an idea for tuning without a signal generator, too.

T.

:Norm knows how to align by ear for perfect station spacing. I do, too, but I forgot how, since I usually use a generator now. I believe that I fix the low end with the IF transformers, and the high end with the oscillator trimmer. If your radio has an oscillator padder (series trimmer), things can get ugly. Do not lose hope, though. When you turn the screws too far, you don't ruin the transformer. You just need someone else to help you re-tune it, if you can't do it yourself.
:
:I think that Peter, or someone else, came up with an idea for tuning without a signal generator, too.
:
:T.