11-12-2008, 01:00 PM
This is my first of what I hope will be many posts on the board.
I 've been working on a Philco 90 mid-model (single 47 tube type) for a few days now. I'm still green when it comes to restoration (I had the good fortune of having two agreeable projects in the past, a Crosley tombstone and an Airliner floor model that only required recapping, a bit of tuning, a resistor and a couple of replacement tubes).
The 90 didn't work when I got it, but after replacing the cord, rebuilding all the Bakelite blocks (that really cleaned up the squealing and the signal!), replacing the bad volume control, replacing a few rotten wires and tweaking the tuning, I've got it working. Signal is strong and I'm picking up all my stations. My problem is, looks like someone tried their hand at replacing the electrolytics at one point. There were two replacement 10mfd caps in the place of the old cans. I look at the parts list for the unit and it shows two cans, each with a 10mfd and a 6 mfd electrolytic in them. Am I safe to leave these two 10 mfd caps in? How were those cans wired originally? Where does the 6mfd caps in the parts list come in?
And a second question: there is a slight 60 cycle hum to the radio too. All caps have been replaced with the exception of the tone control. Should these be replaced? Also, do the power transformers have any caps in them?
These are probably rookie questions to you guys, and I'm sorry for asking so many but any help would be appreciated.
I 've been working on a Philco 90 mid-model (single 47 tube type) for a few days now. I'm still green when it comes to restoration (I had the good fortune of having two agreeable projects in the past, a Crosley tombstone and an Airliner floor model that only required recapping, a bit of tuning, a resistor and a couple of replacement tubes).
The 90 didn't work when I got it, but after replacing the cord, rebuilding all the Bakelite blocks (that really cleaned up the squealing and the signal!), replacing the bad volume control, replacing a few rotten wires and tweaking the tuning, I've got it working. Signal is strong and I'm picking up all my stations. My problem is, looks like someone tried their hand at replacing the electrolytics at one point. There were two replacement 10mfd caps in the place of the old cans. I look at the parts list for the unit and it shows two cans, each with a 10mfd and a 6 mfd electrolytic in them. Am I safe to leave these two 10 mfd caps in? How were those cans wired originally? Where does the 6mfd caps in the parts list come in?
And a second question: there is a slight 60 cycle hum to the radio too. All caps have been replaced with the exception of the tone control. Should these be replaced? Also, do the power transformers have any caps in them?
These are probably rookie questions to you guys, and I'm sorry for asking so many but any help would be appreciated.
