[ARC5] What the heck is a "1/2 harmonic Q-5er?

[Hubert Miller]

So maybe I finally understand this, maybe not.
In the video, the guy's BC-453 is tuned to 420 kHz. That means osc = 420 + 85 = ~505.
Harmonic = 1010.  
Harmonic - 915 kHz BC-348 IF = 95 kHz. Maybe one or the other is not aligned quite right ?
Should be 85 kHz. 

There should be another point, I think, on the 453 dial where this would work.
BC-453 dial = 330 kHz. Osc = 330 + 85 = 415. 
415 x 2 = 830;  915 - 830 = 85 kHz.  

For the ARC-2, the challenge is, the IF continuously varies with the main tuning. What fun 
that is. I think, IF the above stuff is correct:
3885 kHz = ARC-2 IF  @ 1295 kHz.
1295 kHz - 85 kHz = 1210 kHz. 
If BC-453 is set to 520 kHz, osc is at 520 + 85 = 605 and second harmonic is 1210 kHz. 

Of course, I may have gone of the rails at point A. 
-Hue