Heathkit SB-10 Series Troubleshooting Manual page 42

Receive Mode Bandpass Response
With power off, connect the output of the sweep (tracking) generator to V11 pin 1
through a suitable DC blocking capacitor. Connect the demodulator probe or spectrum
analyzer input to V12 pin 2 also through a suitable DC blocking capacitor. Set the center
frequency to 8645 KHz with a sweep width of 2 MHz.
With power applied, you should see a response that looks like the following example
(Marker 1 is at 8395 KHz, Marker 2 is at 8645 KHz, and Marker 3 is at 8895 KHz).
Observe that the pass band is within +/- 3dB over the desired span.
Figure 2. Bandpass Response (Receive Mode)
To tune the transmit response, tune the middle trimmer cap for peak signal at 8645 KHz
(Marker 2, center of the bandpass) and the bottom trimmer cap to provide a symmetrical
frequency response between the upper and lower ends of the pass band (Markers 1
and 3).
Note: need to verify that it is indeed the bottom trimmer cap.
Alignment Page 42