This page deals with I.F. alignment and how to go about it.


In the picture above,the two silver cans contain the i.f. transformers



You need a signal generator to align the i.f's correctly



And a set of plastic trimming tools to turn the cores,DO NOT USE SCREWDRIVERS,these are too hard and if you have tight i.f. cores the screwdriver will almost certainly break them,plastic on the other hand will tend to break or bend before the core cracks.

I.F. ALIGNMENT PROCEDURE

First of all,i assume the set is in a working condition and capable of producing at least a weak radio station.
1.First of all connect the ground lead(black) of the signal generator to chassis,connect the signal lead(red) to the control grid(g1) of the frequency changer. This may be the top cap(in an older set) or try to connect it to one side of the tuning capacitor. It is important to mention here that valves take time to warm up and indeed valve characteristics are completly different cold than when hot so you should never try to align I.F. stages cold. always wait 15 minutes or so for the radio to warm up.

2.Inject the correct i.f. frequency into the frequency changer control grid,using as low an output as you can,other wise the automatic volume control(avc) will come into operation and give you a false reading. NOTE IF YOU ARE UNSURE OF THE CORRECT I.F. FREQUENCY PLEASE USE THE CONTACT PAGE STATING THE MAKE OF RADIO AND MODEL AND I WILL DO MY BEST TO ASSIST YOU.

3.At this point it is helpful to have a circuit diagram in front of you to show you which of the coils are which. Its best to tackle one can at a time as there are usually two coils in each can. You can do either one first,but i prefer to work backwards i.e the can nearest the detector valve to the one nearest the frequency changer. You should be hearing a steady tone,keep turning the output of the signal generator down(to prevent the avc kicking in),each i.f. coil should peak as you turn it,leave it at the highest point of the peak(maximum output).

4.Keep repeating this until you are satisfied that the performance is up to standard. NOW YOU SHOULD ALIGN THE R.F. STAGES....SEE R.F. ALIGNMENT PAGE.