Thread Rating:
  • 0 Vote(s) - 0 Average
  • 1
  • 2
  • 3
  • 4
  • 5

Philco 89 Bakelite Block not in schematics
#1

Hello and help! Working on an 89 code 123. BC/SW. Everything was fine until coming to part#9 3615XG. Info I have:
Part#'s from Riders and orig. Philco Service manuals. Riders and Philco manual show this part as 3615XG(.0015/.05). In radio was 8174B(700pF/.05). This radio uses a 36 tube. Sets made before 1 Sep 34 used the 36 tube. 36 oscillator problems on the cathode resistor indicated the resistor needed to be replaced down to 7.5K. Will find that out if I get this thing working! Question is-which block condensor is right? Previous repairman put in a 700 pF and .1 caps to replace the ones in the block. All wires where desoldered except for the 15k (part#8) resisitor. The wire with the 15k resistor goes to the oscillator coil. The 5K (part#18)was disconnected and the wire with it goes to the detector coil. Both replacement caps are hooked up right. Both caps were soldered to the chassis ground on the volume control. I,m basically looking for info on how the correct block was connected.
#2

Hi Kenny

Sounds like you're going by Service Bulletin 146B, which is for Model 89, Code 123 - BUT with the Type 77 tube as det-osc. instead of Type 36. This Bulletin does call for 3615-XG, which is NOT what you want if your set uses a Type 36 tube. 8174-B is correct in your set, which is 700 pF and .09 (not .05) uF.

700 pF and 0.1 uF is a correct replacement.

Don't use another 15K cathode resistor! Use a 10K or, if necessary, 7.5K.

And be advised the oscillator coil may very well need to be baked (yes, literally baked) and rewound to make the set work. See the "89 from H**l" thread here in the Phorum for more details.

--
Ron Ramirez
Ferdinand IN
#3

Thanks for your quick reply! Will take advice and see what I can do with this radio. I like to see what I can do on my own-so if coils need to be redone-how do I go about it-What gauge wire do I use? If I make a blotch of it will consider your coil repair services-Kenny Kidd




Users browsing this thread: 1 Guest(s)