03-03-2018, 08:51 PM
Thanks Russ. I have no cabinet either. It's on a shelf in my shop and I've been enjoying it immensely for several hours a day. FM is SOOO much quieter in a modern house than AM and the extended frequency range is great. I used to do a bit of recording and mastering CD's so high end audio is part of my blood. No stereo here, but hey, can't talk about imaging, sound stage, depth, instrument placement etc. while walking around in the shop anyway.
Capacitors... I re-stuffed all electrolytics, tubular paper caps, and oil filled caps. I am afraid there are a LOT of what look like mica's that are probably molded paper. I was hoping to avoid those, but someone on the Scott forum said they were paper and to replace them, particularly in the noise reduction section. I don't use that so it is in reality out of the circuit. If you think that some of those caps could be causing the hum on de-tuned, weak FM stations then I'll have to look into doing that. How do you make those look original? Most of them are Sangamo and Tobe. Do you know anything about them? The only time the hum is problem is if the frequency drifts a tiny bit, which it does until on for quite a while. No auto frequency control. I do have to wait for silence to fine tune the hum out. My favorite classical station is fairly weak so the hum becomes noticeable on quiet passages, and I have to re-tune. I do notice sometimes, though, that high frequencies like sibilance in a speaking voice seem a bit distorted. But not always, and not on all stations. Is it possible that some stations broadcast with distortion? maybe I expect too much from a 1947 radio!
I'd like to try to do another alignment someday. I need an excuse to purchase a spectrum analyzer. Would such an instrument aid in aligning the FM section? (Say "yes" so I can justify the purchase!) I watched a YouTube of Carlson's Lab doing an alignment on a Hallicrafter, I believe, and it looked useful. In fact, he said it was mandatory for proper alignment of that radio.
Capacitors... I re-stuffed all electrolytics, tubular paper caps, and oil filled caps. I am afraid there are a LOT of what look like mica's that are probably molded paper. I was hoping to avoid those, but someone on the Scott forum said they were paper and to replace them, particularly in the noise reduction section. I don't use that so it is in reality out of the circuit. If you think that some of those caps could be causing the hum on de-tuned, weak FM stations then I'll have to look into doing that. How do you make those look original? Most of them are Sangamo and Tobe. Do you know anything about them? The only time the hum is problem is if the frequency drifts a tiny bit, which it does until on for quite a while. No auto frequency control. I do have to wait for silence to fine tune the hum out. My favorite classical station is fairly weak so the hum becomes noticeable on quiet passages, and I have to re-tune. I do notice sometimes, though, that high frequencies like sibilance in a speaking voice seem a bit distorted. But not always, and not on all stations. Is it possible that some stations broadcast with distortion? maybe I expect too much from a 1947 radio!
I'd like to try to do another alignment someday. I need an excuse to purchase a spectrum analyzer. Would such an instrument aid in aligning the FM section? (Say "yes" so I can justify the purchase!) I watched a YouTube of Carlson's Lab doing an alignment on a Hallicrafter, I believe, and it looked useful. In fact, he said it was mandatory for proper alignment of that radio.