02-02-2018, 12:03 AM
Hello all. New to this phorum but have read as a guest for quite a while. I've been working on a model 18 for about a month now. Replaced all caps and ecaps, all resistors that were out of spec, rewound the small coils on the outside of the oscillator and detector coils. I think you call them tickler coils. Found a broken wire on the inside of the antenna coil- tore it apart and spliced it. Good continuity afterwards. Checked all tubes - all ok. Ohmed out all transformers and coils- all good except the 2 coils I rewound are about 2X the ohms on the schematic( the detector primary is supposed to be 3.7-is now 6ohm and the osc. pri. is supposed to be 3.4- is now 6 ohms). Powered it up with variac and all seemed to go OK but got very little reception and nothing above 1100khz. So I used SG and got good tone in every stage. Thought I should do an alignment so following the instructions on the Philco schematics from Radio Museum I set the SG on ant. term. and grd. on grd. term. They said to put output meter on output trans. or the plates of the 2 output tubes. I tried the 2 42 tube plates and powered everything up and blew out the 80 tube. I have another 18 chassis that has not been tampered with except for the 2 ecap cans and the 10uf ecap can which was missing. I made sure when I installed that cap the pos. went to grd. I tried it again with the meter on the voice coil and could not get a sound out of it. Put the meter on the plates and blew another 80 tube and a ecap. Replaced both and turned on slow with variac and it stayed on. Hooked up an antenna and 1 very weak station for 30 sec. then fades out. Moved dial down- got another station then faded out. Now nothing. I'm lost now. I know this is a long narrative but I thought you guys would need as much info as possible. Any ideas or instruction would be greatly appreciated. Thank You madsowry