[morzh]

The 20 pot has two sections: one is the Antenna attenuator, the other is the cathode bias one.

[dconant]

To clear things up a bit. The Philco pot (33-5040) is single gang 3 terminals with AC switch. The picture shows how my pot is wired and the description of the post from the Philco parts catalog. Note the 32K resistor on my drawing is not on the early or late schematic. Looks to me like someone has wired the pot trying to use both the early and late schematic.

[morzh]

Oops, sorry. I've answered a question no one asked.

[MrFixr55]

That's OK, Morzh, I do that all the time. If we could catalogue the answers to questions that no one asked, when they do ask them, the answer is there. It would be like we're clairvoyant!

[morzh]

Well, now you ask that question and there we are, the time travellers.

[MrFixr55]

Hi Dconant,

Yeah, I think someone tried to combine the 2 functions.  I don't think it will work.  In the early 27 schematic, the field coil and the 1K Ohm potentiometer's resistor is in series, across the B Supply, between B+ and Chassis ground, which represents B- and C+  the wiper goes to the cathodes of the 2 RF amp tubes.
 
For (somewhat) more clarity, I cut away the power supply from the rest of the schematic.
   

I think that to get this to function right, ensure that the Antenna coil and tuning cap are wired according to the schematic for the earlier model (Volume Control controls cathode bias only.  you may have to put a 2K resistor across the 2 "end" connections on the pot that are not the wiper contact.

[dconant]

Thank you MrFixr55 I will do that. I'll post back when I have that done. Might be a few days though.

Dan

[dconant]

Back at work on the Gloritone. The antenna secondary coil is open. Not 100 percent sure it is the secondary. Based on what Buzz1151 said about his antenna coil I'm going with the secondary. His coil looks like mine viewing the wires inside the coil form. Notice in the picture AntCoilSplice it looks like two turns have been cut right next to the heavy white wire that makes one turn around the core. I'm wondering if they should be connected to the heavy white wire. Notice in the AntCoilTop picture the white wire at the right is not connected to anything but just tied off. Also notice just o the left we see the same heavy white wire. That connects to a terminal at the other end of the core. Notice in the AntCoilBottom picture we see the heavy white wire on the right terminal as well as a dark wire. The dark wire connects to the coil inside of the tube. Also notice the terminal on the left has a copper and smaller white wire. The smaller white wire connects to the inside coil. The copper wire connects to the outer coil. I am pretty sure this is factory based on how neat it is. I can't tell if Buzz1151 coil has this splice as he does not show or comment on it. It appears to me as if the two coils are wired in parallel but that can be. I'm really lost here. Any ideas? 

Buzz1151 video: https://www.youtube.com/watch?v=7dHXHhTCZTo Starts at 33:30.

Thank you,
Dan

[Arran]

Dan;
If the two windings have continuity then they way they are wired makes sense. According to the schematic the primary and secondary have a common ground connection. The thick white wire might be either a tickler, or it might be a sort of "Gimmick" capacitor, but probably the latter to prevent oscillations.
Regards
Arran

[MrFixr55]

Hi Dan,

Don't let this issue stop you.  If you live in a strong signal area,  finish all the other tasks on the radio and hook a length of wire up to the 2nd RF tube.  Yu should be able to tune in stations.

The white wire is not shown on the schematic but I bet that it is original to the radio.  It is known as a "gimmick" and it is kind of a loose coupling between the primary and secondary in some sets.  if the connected end is grounded, then it may be there to prevent oscillations in the circuit.

I am going to go out on a limb and state that the outside winding is the antenna side and that the "open" is due to a lightning hit.  It appears to be burned in your picture.  clean it up and bridge the burned out section.  this should get you going.

Hope this helps.

[dconant]

MrFixr55,

What I ended up doing is removing the two turns and fastening what was left of the second turn to appropriate terminal. I left the white wire as it was. The idea of it being a gimmick makes sense too me. I now have continuity on both coils. It will be a while before I know if the set works.

Dan

[MrFixr55]

Hi Dan,

That should work. If it is the primary, it is not tuned. If it is the secondary, you may have to add capacitance or crank down on the "trimmer" (a screw) on the section of the tuning capacitor that tunes that stage. If it does not "peak", you may have to add capacitance across the coil (just a few pF) or add the missing turn (it is OK to splice the turn in, I hear that just that Philco apparently did that on early sets when they ran out of wire in the middle of winding a coil.

Keep us posted. TRF sets are relatively easy, much easier than some of the early superhets with autodyne first detectors (oscillator / mixers).

[RodB]

It seems these radios of the 1930s were experiments when it came to antenna signals and getting as many stations as possible to come through. We can only assume the direction of the design, but I think many antenna designers of that time were trying to come up with a device that would lower the noise level and still bring in the distant signals. What looks like a simple rf transformer in the schematic has surfaced as a mystery. This is quite often one reason why we do these restorations.