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Philco model 18 (code 121) - HELP!
#69

Morzh – The bottom resistor on my schematic (by the way, I have a PDF, can I upload it somehow?) is #62 and that one IS a 50K resistor. I’ll check the Ohms when I get home, it might be 22K, that rings a bell, I was up late last night so everything is a blur. Looking at the schematic now I see what confused me, in real life (and I’m talking about looking at the actual radio and not the schematic) the GND end of the 32K resistor is soldered directly to part #20 (which is a 0.15ufd cap)—ie it’s not soldered to ground like I think it should be anyhow. However, if you look at the schematic, that #20 cap ALSO goes to ground but there are no lines on the schematic that connect #20 to the 32K resistor! I think I spent about ½ hour trying to find a path on the schematic that linked up the #20 cap to the 32K resistor! HA! Those tricky b@stards, I guess it is hooked up correctly since both the #20 cap to the 32K resistor go to ground, right?

Also, what is ‘Rtrans-prim’? The resistance of the ‘output transformer’? And if so, can I find the resistance of it by just using the two tabs on the bottom of the chassis? Or does that resistance change while in the ‘system’ as well?
Thanks.

Jerry – Lucky for both of us I copied your post before you deleted it! I printed up the 118 Philco schematic. Looks like you have 4 caps, and mine only has 3. You may have trouble reading the schematic for the model 18, so here is the breakdown with comparison to your model 118. I do have a question at the bottom that I hope you can answer for me.

• #46 (A) Is a 1.0 ufd cap that T-connects to #45 & #47 the 50K/0.1MEG [#40 (A) and #41 & #39 on my model] – This model 118 schematic corresponds exactly with mine.
• #46 (B) Is a 1.0 ufd cap that is parallel with #60 the 6.5 Wirewound [#40 (B) and #49 on my model] – This model 118 schematic corresponds exactly with mine.
• #46 © Is a 2.0 ufd cap that T-connects to #67 & #68 the 32K/50K [#40 © and #61 & #62 on my model] – My model 18 schematic is a bit different.
• #46 (D) T-connects to #67 & #68 (the 32K/50K) –I’m having trouble finding this one on your 118 schematic, but I hope you know where it is! That thing is hard to read!

Ok, now for my question. Our ‘A’ & ‘B’ are the same and I have those hooked correctly. I don’t have a ‘D’ so we are only talking about your #46 © the 2.0 ufd cap connection or rather #40 © and #61(32K) & #62(50K) on my model.

For #46 ©, if you look at your 118 schematic, you see there is a wire connection from the (+) end of the 2.0 ufd cap going to the 6A7 tube? Ok, I have almost the exact same thing on mine except the connection is going to the #78 tube not the 6A7 tube.

My question is, on your 118 model, can YOU make a 4-way (‘CROSS’) wire connection with the #6A7 tube wire, the 2.0 ufd cap, the #67(32K) & #68(50K) resistors? Because, now that my 3 caps are out of the tube, that’s the only way I could think to hook this up. My current connection for #40 © is this 4 way connection of the #78 tube wire, the 2.0 ufd cap, the #61(32K) & #62(50K) resistors.

And if not, do you have another suggestion? This isn’t a trick question by the way, it looks like there shouldn’t be an issue, I only question it because it didn’t look like that’s how this set was originally made, and I don’t want anything to blow up.
Thanks.


Messages In This Thread
RE: Philco model 18 (code 121) - HELP! - by morzh - 02-07-2013, 10:22 PM
RE: Philco model 18 (code 121) - HELP! - by morzh - 02-08-2013, 10:32 PM
RE: Philco model 18 (code 121) - HELP! - by Arran - 02-08-2013, 10:49 PM
RE: Philco model 18 (code 121) - HELP! - by morzh - 02-09-2013, 02:21 PM
RE: Philco model 18 (code 121) - HELP! - by morzh - 02-09-2013, 05:57 PM
RE: Philco model 18 (code 121) - HELP! - by morzh - 02-09-2013, 06:12 PM
RE: Philco model 18 (code 121) - HELP! - by morzh - 02-13-2013, 08:40 PM
RE: Philco model 18 (code 121) - HELP! - by morzh - 02-21-2013, 05:25 PM
RE: Philco model 18 (code 121) - HELP! - by morzh - 02-28-2013, 06:04 PM
RE: Philco model 18 (code 121) - HELP! - by morzh - 03-07-2013, 04:16 PM
RE: Philco model 18 (code 121) - HELP! - by morzh - 03-07-2013, 11:20 PM
RE: Philco model 18 (code 121) - HELP! - by morzh - 04-17-2013, 01:25 PM
RE: Philco model 18 (code 121) - HELP! - by Pithicus999 - 04-18-2013, 08:03 PM
RE: Philco model 18 (code 121) - HELP! - by morzh - 04-18-2013, 08:48 PM
RE: Philco model 18 (code 121) - HELP! - by morzh - 04-18-2013, 09:49 PM
RE: Philco model 18 (code 121) - HELP! - by morzh - 04-29-2013, 10:02 PM
RE: Philco model 18 (code 121) - HELP! - by morzh - 06-12-2013, 01:37 PM
RE: Philco model 18 (code 121) - HELP! - by morzh - 06-13-2013, 08:33 PM
RE: Philco model 18 (code 121) - HELP! - by morzh - 07-23-2013, 10:33 PM
RE: Philco model 18 (code 121) - HELP! - by morzh - 07-24-2013, 11:11 PM
RE: Philco model 18 (code 121) - HELP! - by morzh - 08-02-2013, 05:06 PM
RE: Philco model 18 (code 121) - HELP! - by morzh - 08-21-2013, 10:26 AM
RE: Philco model 18 (code 121) - HELP! - by morzh - 12-17-2013, 10:58 AM
RE: Philco model 18 (code 121) - HELP! - by morzh - 12-19-2013, 12:47 PM
RE: Philco model 18 (code 121) - HELP! - by morzh - 12-19-2013, 08:48 PM
RE: Philco model 18 (code 121) - HELP! - by morzh - 01-17-2014, 04:05 PM



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