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Radio Bar 60 B Rebuild
#1

Hello All, I am having some trouble (like many of us I guess) trying to bring a 60 B back to life. This one is out of a Philco Radio Bar. I am about halfway through the recapping process. I completed the#20 Capacitor bank (and boy I hope I did this right-I have been following a similar thread on this forum for guidance) and I now have to do the Electrolytic cans and then the bakelight blocks. I don't want to go thru the trouble of cutting into the cans and restuffing them. Can somebody tell me exactly how to wire the new electrolytics and where the positive and negative leads should go? Any picture or drawings would be a great help.
Right now when I turn the set on, I get nothing but a loud hum or buzz through the speaker, with no change in volume when I turn the volume knob. I am hopefull that this is just due to the capacitors being in need of replacement. The other poroblem is that the dial lamp is not lighting up. I have a new lamp installed. Any ideas?
Once I get the radio playing and the weather warms up, I will be able to tackle the cabinet restoration.

Thnaks much for all your help.
#2

You may want to read this page on my site:
http://www.philcoradio.com/tech/60evol.htm

The negative leads of both electrolytics (45) and (46) connect to B-, NOT ground. Electrically, this is the junction of the center tap of the high voltage winding of the power transformer and the top of "B-C" resistor (47) as shown on any Model 60 schematic.

The positive lead of electrolytic (45) connects, electrically, to the junction of the screen grid of the Type 42 tube, the WHITE lead of the speaker wiring harness (which connects to one side of the audio output transformer as well as one side of the field coil). This junction is also part of the main B+ feed for the entire set.

The positive lead of electrolytic (46) connects to the junction of one side of the 80 rectifier filament and the GREEN & WHITE lead of the speaker wiring harness, which connects to the other side of the speaker field coil.

Check wiring to the dial lamp holder.

--
Ron Ramirez
Ferdinand IN
#3

Oops, Ron and I overlapped postings. Gotta run.
------------
Figuring out how to replace the electrolytics in a power supply usually takes some creativity to avoid flying leads. Since you can't simply parallel new caps on the old cans, terminal strips may need to mounted nearby to get the wires off the old capacitor cans.

Assume this is Rider Philco 4-32. The negative side of the caps connect to the center tap of the high voltage winding. Normally the cap cans had an insulating washer between the can and chassis to make this connection possible and included a solder lug which may be reused to make a negative connection for the caps.

Power up the radio and perform basic voltage checks. Otherwise you are working blind.

As fas the dial lamp not working typically the lamp receptacle has to taken apart and rebuilt with insulating phenolic washer. The rubber washer have petrified not allowing the spring to put pressure against the lamp. Think Ron or Chuck has a help page concerning this known issue.

Good luck on the restoration!

Richard
#4

Mr. Ramirez and Richard, thanks for the replies. I have been busy at work, but tonight I will tackle this using your insight and let you know what happpens. Thanks again, SF/MG
#5

The Model 60 would not have had any rubber in its dial lamp socket originally. Philco did not start using a rubber insulator in its dial lamp sockets until the 1937 model year. Maybe some late 1936 models also - not sure at this time, but definitely 1937 to 1942.

The page Richard refers to on dial lamp socket rebuilding is indeed on my site:
http://www.philcoradio.com/tech/lamps.htm

--
Ron Ramirez
Ferdinand IN
#6

Ron, I read your directions and with respect to the 8 mfd cap part 46 and how it is conected both in terms of the pos and neg leads are there just as you described.it is easy enough to see. Part #45 is confusing me. There is a brown wire that runs for the ecap lead to part 17, but nothing I see connects to the 42 tube. There also is a thin wire that connects to the green wire of part 46 which makes sense for the neg lead.. What am I missing? Thanks for your help.
SF/MG
#7

There MUST be a common lead (or leads) which runs between parts 14, 17, 26, 24, 34, 42 and 45 as well as the primaries of IF transformers 16 and 25, one end of the field coil and the screen grid of the Type 42 output tube. If there is no continuity between those parts, the set will not operate.

--
Ron Ramirez
Ferdinand IN




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