Can a B&K Precision Model 415 Sweep Generator be used on early sets (1949-1952)?

I don't think so. I believe it has a fixed IF of around 44 MHz.

You are right...

IF (10 Standard Frequencies)
a. 39.75 MHz (ADI PIX)
b. 41.25 MHz (SOUND)
c. 41.67 MHz (CHROMA)
d. 42.17 MHz (CHROMA CARRIER)
e. 42.67 MHz (CHROMA)
f. 42.75 MHz
g. 44.00 MHz
h. 45.00 MHz
1. 45.75 MHz (PIX)
j. 47.25 MHz (ADI SND)

Bob - I've been watching your 24A12 tuneup on Youtube, and wonder if you or anyone else, has a recommendation for a sweep generator with a marker-adder in one unit - that will work with the older TV's. I have a Jackson 106 RF generator I use for radio alignment I really like - it's solid and accurate, and I also have a Precision E-400 Sweep Signal Generator, but that is going to take a complete restoration... Any recommendations on an reasonably priced 'all in one' unit to look out for?

Thahis

Although mine has some issues, I think the EICO 369 is a pretty good choice. I love my Wavetek 1002 and 1080, but they can be hard to find / pricey and you'll still need an external variable marker generator. I'm currently using a Leader 17A for my variable marker gen. It's quite accurate.