[Hallicrafters] SX-28A Alignment

[Dream Lobo]

Greetings
I am currently restoring two SX-28A's and I situation came up with the first one which is finished minus the alignment. The IF frequency of 455 khz is what the manual says to set the signal generator at when beginning the alignment which I did, but, the receiver seems to actually want a frequency quite a bit removed from that for max gain. I have seen this before in other receivers but the difference was slight so I used the slightly different frequency as the one I set the signal generator on. Only a few hundred cycles or so. In the case of this SX-28A, max gain seems to be around the frequency 451 khz which is a much larger difference that I have encountered before. I did the first part of the alignment using frequency 455 khz but I am thinking that the gain doesn't seem to be what it should be. The question is, have any of you encountered the same type of situation and if so, what did you do about it. I am think that maybe I should use the frequency that seems to be the actual frequency that the crystal filter wants to see. Any thoughts on this matter would be most welcome. Also, I have need of a band switching knob for an HT-37. If anybody has one they can part with please let me know.

Regards & 73
Ae8o
Tom