02-03-2013, 12:21 AM
Ron,
Yes, I bought the service literature on this radio, so have the alignment procedures, etc.
Still no love getting bands 4 and 5 to oscillate below the middle of each band. There doesn't seem to be any resistance between the rotor of the tuner and the frame, but I'm going to see if bonding the rotor with solder wick to the frame helps.
Of note is this:
Looking at the LO output on my scope (cathode follower, no load on the LO), the BC band is strong, but quite distorted, with the bottom of the waveform truncated and flattened. Band 2 is similar. Band 3, 4, and 5, where they oscillate at all, are much closer to a natural sine wave, but are much lower in amplitude.
Yes, I bought the service literature on this radio, so have the alignment procedures, etc.
Still no love getting bands 4 and 5 to oscillate below the middle of each band. There doesn't seem to be any resistance between the rotor of the tuner and the frame, but I'm going to see if bonding the rotor with solder wick to the frame helps.
Of note is this:
Looking at the LO output on my scope (cathode follower, no load on the LO), the BC band is strong, but quite distorted, with the bottom of the waveform truncated and flattened. Band 2 is similar. Band 3, 4, and 5, where they oscillate at all, are much closer to a natural sine wave, but are much lower in amplitude.
![[-]](https://philcoradio.com/phorum/images/bootbb/collapse.png "[-]")
