[AMRadio] Receiver IF alignment question

[JAMES HANLON]

Jim,
 
I agree that it sounds like your signal generator was puttin out too much signal.  Back it off until you hear a fair amount of background noise along with the modulated tone, and then peak up the transformer adjustments.  If you are concerned about the modulation being FM rather than AM, just turn all of the modulation off and do one of the following.  1) Turn the bfo on, set the bfo frequency for a pleasing pitch, and peak up the transformers for maximum audio out as read by your voltmeter across the speaker.  or 2) Turn the AVC on, adjust the signal generator output for a fairly low reading on the S-meter (or if there is no S-meter put a vtvm on a dc volts scale or a DVM from the AVC line to ground and adjust the signal generator output for a moderate change in the AVC voltage, somewhere between zero and saturation.)  Then peak up the IF transformers as indicated by maximum S-meter reading or maximum (negative) AVC voltage reading, reducing  the signal generator output as needed to keep the S-meter no higher than mid range or to keep the VTVM on the AVC line no higher than half-way to saturation.   Backing off the signal generaor should avoit the "messy and raspy" problem.  
 
I generally think it is easier to read a meter needle when tuning for a "maximum" point than to maximize a scope wave-envelope pattern, so I'd stick with the meter as an indicator.  
 
Hopefully, this alignment procedure will take care of your birdie problem.  If it doesn't, we'll have to work a bit more on that later.  Let us know how it works.
 
Jim, W8KGI