[Radioroslyn]

> it looks like the only way to adjust the 3 stages is to physically adjust the pulleys on each shaft for maximum signal.

That's it. A lot of the older trf set are set up that way. The ones that use #26 tubes or triodes may have a neutralization adjustment. Triode AK sets battery and early ac like the model 20 or 40 use a resistor in series w/the grid lead to prevent oscillation.

[rfeenstra]

I was able to repair the RF transformer.  The break was right next to the terminal so not much of a problem.  That allowed a MUCH greater sensitivity.  by increasing the spring tension on the tuning capacitor shafts, they settled into a more centered travel giving stations all accross the dial.

This is the first non AGC radio I've played with and can see/hear that AGC was a tremendous improvement in the day!  The Philco 96 TRF performs so much better than the AK 55.

Voltages are indeed much higher than they should be.  Interestingly, several resistors had been changed a long time ago to higher values, perhaps to compensate for 60 cycle rather than 25.  Not sure what I'm going to do as it will take a pretty good resistor to drop the line voltage.  Since I'm not too impressed with its performance, I may just leave it for an occasional demonstration and keep it for show.

[rfeenstra]

Some before and after photos.  Still need to work on the case.  Thinking of a complete paint job, but don't like that kind of work!

               

[Radioroslyn]

Looking  Great!!!!
I was never one for that strip down start from the ground up unless it was really really bad. When I was working it just took too much time and patience. Now that I'm retired it seems to be quite possible for me to do.

AVC is a big + on these older sets especially if you live in a city where there are some big guns transmitting. At night it's difficult to tune across the band without getting knocked off your chair by a powerful station.

I have a Philco 76 that I  need to revisit. One of the 45 output tubes looses filament voltage (bad connection somewhere) but was toying with the idea of adding avc to it. Takes about 6 additional parts and have to reroute the volume control to the audio side of thing vs the ant.

One of these dayz...

[rfeenstra]

Thanks!  I don't think it's worth adding AVC to this.  I'll keep it "somewhat" original. Not fully since some mods had been done in the past and in playing with it, I've done further changes in the resistors to get bias and plate voltages a bit closer to the specs that I have.  It's playing pretty good, though it seems a bit more distorted than other radios I've worked on and tone quality is less than stellar!  I don't know if the universal interstage audio driver transformer has anything to do with that, but at least it works. I did calculate a series resistor for the line voltage and it's not as bad as I thought it might be, so I ordered one that will get the line voltage down to 105 vac or so.  That seems to bring things down to a reasonable value.  This radio will spend virtually all of its time sitting an a shelf looking pretty, and, as I said before, will only be turned on for a quick demo.

[rfeenstra]

I decided to revive this project.  The radio has been sitting on the shelf for nearly 3 years since I restored it.  The coffin cabinet has been sitting on the floor, in my way, for the same amount of time.  I decided to get it out of my way by restoring the cabinet since the original finish was severely disfigured.  Here is the F-2-A speaker repainted.  The fine gold stripes were a pain and certainly not perfect, but the best I can do.  The grille cloth is original and a bit stained, but it will remain. The radio is playing Zoomer radio 740AM as I type this.  This radio seems especially sensitive to signal strength.  Makes me appreciate AVC all the more!  The rest of the cabinet is painted, but I am waiting for some rivets to re-attach the escutcheons.  Will post a pic of the finished product when I get those.  Then the completed radio will go back on the shelf.  I don't really enjoy listening to it!

           

[rfeenstra]

This radio is finished.  It certainly is not a radio that I will be using.  It will go on the shelf and look pretty.  It's fairly sensitive and so the Local/Distant switch is very necessary.  When tuning, I have to keep one hand on the volume control.  The lack of AVC is very apparent.  Since it is a TRF design, selectivity is not great.  Strong adjacent channels cause a lot of interference at night.  Since this was a popular radio in its day, it's nice to have an example.  It does reduce my desire to restore my other 55 that is in a Kiel table.  But, some day...

               

[klondike98]

Beautiful job!