I have a Technics SA5400X receiver that I got for parts and just completed its restoration. The tuner seems to be working, although reception is quite weak, it only picks very few stations and it is pretty noisy. I therefore decided to use it to try my first ever alignment. I currently do not have a distortion meter, but I figured I would use an oscilloscope and reduce distortion by eye/ear for now, my main goal at this stage is to try and grasp a bit better the workflow/procedures and, mostly, to learn something new. I got a service manual with the alignment procedures, I have a scope and I have access to an HP 8644A RF signal generator. - First, the FM alignment procedure appears to want me to set the RF SG for different levels of FM percentage modulation. This is quite confusing to me: am I correct to assume that if the modulation frequency bandwith is +/- 75kHz, then 100% modulation is the entire 150kHz bandwith around the carrier frequency and a 30% modulation is 30% of that, i.e. the carrier frequency +/-22.5kHz? - Second, the alignment procedure defines output levels in (positive) dB, e.g. SG 98MHz (100% modulation with 400Hz), Output 72dB. Am I correct to assume that I should set the SG for an output of -72dBm? Am I also correct to assume that whenever no output is specifiefd, then I should set the SG at 0dBm? I tried setting the SG with a 90 MHz and 106MHz with a 400Hz modulation signal, I connected the SG to the 300 Ohm antenna inputs with a dummy antenna as specified in the service manual, and I can easily pick the 400 signal both on the oscilloscope and through my speakers. There seems to be quite a lot of interference though, and I need to crank up the volume quite a bit to see a clean sinewave. I checked the specs of the SG, and it seems to have a quite high FM distortion (I have the Option 04, so I get a 1% distortion), double or example the amount of distortion of an HP8656B. Given that I don't have a distortion meter and the spects of the tuner are around 0.7%THD in stereo mode, I don't think that is too much of an issue for now. However, if I want to play more with tuner alignment, should I get a lower distortion SG? As always, thanks for the help.