[462ron]

OK, I need to rename this thread to say..Eico 368 TV/FM Sweep Generator instead of the current title..Heathkit Sweep Generator TS-4.. as I don’t know how to rename my thread. The reason being my Heathkit is dead in the water as it needs a part that is unobtanium! I am now working with my Eico 368.

So I have built the “broadband demodulator” as required (see last post above #14) and got the desired pattern they expect which is two parallel lines, my pattern also has the 10.7 MHz pip superimposed on top ( see attached last photo at bottom)). I have purchased a 9.1Mhz crystal to use for aligning my Philco 52-944 and also purchased a 10.7Mhz crystal for my Zenith 7H-920 I am currently working on.

The problem is when I I run the signal through the radio per Sam’s alignment procedure, I can get the pattern desired from the discriminator but there’s no 10.7 MHz pip on trace anywhere even though the crystal oscillator is dead on according to my frequency counter. See first photo below.

I have altered this generator by installing a switch so I can kill the sweep oscillator thus leaving me with an accurate IF signal. I used this crystal controlled signal to do a step by step alignment with no sweep and got the radio playing beautifully. I could leave well enough alone which I might do but I would really like to know why I can’t see the marker pip on the display. I’ve never done a sweep alignment on a FM radio so I don’t know what I’m doing wrong!

Ron