Part 2 Disassembly & Chassis Repair: Philco 46-1201 "Bing Crosby Special" Radio & Record Player

[@hestheMaster]

This is one unit where having the original Philco schematics and revisions to it are a must. As time went on past repair persons put parts in it to get it to work and sent the then owner on their way. There is a reference to using a 50X6 rectifier in code 126 for example, in place of the 50Y6 from code 122 . A power resistor of 80 Ohms came before it in either case. With so many changes in components it would be really a good idea to find a schematic and note which revision code you have. Yours is probably a code 128 if it has a permanent magnet speaker in it otherwise it is a code 127 ! Definitely not the schematic shown which is the original code 122. I don't know code version the " made in Canada" ones are but they probably offered it as the code 128 which is the last revision before putting in minature tubes like a 50B5. Great idea on replacing the pilot lamp with LEDs. Seen a site where the guy did just that. You definitely get an A+ for all this effort Mr. B. in getting the thing working again that's for sure!

[@Mr.BrownsBasement]

Thank you for your attention to detail! Before I discovered that the number "706" was important, I had literally spent hours pouring over the revisions of the 46-1201. I wanted to find a match between the set in front of me and a schematic / tube complement in the literature. Code 128 (runs 1 & 2) do indeed use rectifier 50X6 (the only one that uses 50X6) but code 128 also uses Loctal type 50A5 as the output tube. And my output tube is an Octal 50L6! I was beginning to come to the conclusion that I had a chassis which was significantly different than anything mentioned in the literature. But then I found a page on chassis 706. And indeed, the chassis says that it's a 706 made in Canada. Philco Canada (like other Canadian manufacturers of the day) had their own way of doing things. (We Canadians are just like that sometimes!) After comparing the chassis on my workbench to the schematic of 706 it was a near perfect match. There are some differences on my chassis which are minor, mostly being component values (e.g., C403 the "resonant capacitor"). That's why I mused that there might have been different versions of chassis 706. Unfortunately, chassis 706 is poorly documented. What complicates matter is when a repair person makes a change and does such a good job you think it's Factory original. My set had definitely been serviced (possibly even "molested") before I got it. The green 75Ω 10W power resistor was not Factory original! But on chassis 706 there is a resistor R100 in that location marked 80Ω. I'm far from the "Basement" this week but I'm hoping to return next week and shoot the next instalment. Or maybe continue with the PowerBook 160, or one of dozens of other things I have on the go right now. Thank you again for paying such close attention (it keeps me on my toes) and thank you again for watching.