Sir Jim. . . . .

WHAT . .No forthcoming answer to your question? . . . . .but I do, just now see, that Sir Norman has come on with a quick reply, just before I am posting this, but here is a reply, which I hope that will give you your full money's worth.

Radio picks up station(s)very weak (at the) low end of band

How come . . .of your supplied . . .info, that particular sentence just glares out at me ?

I checked schematic and in this case, they were generous to give me 3 pages of referencing, of which I see your specified C2 as being a trimmer sitting atop the frontal portion of the osc section at the front section of the tuning condenser.

It being constructed of a single plate and compressing against its companion mica dielectric spacer. I would expect the totally uncompressed conditon of the trimmer to be exhibiting right at 5-10 mmfd of capacitance, or then the adding of another 15 mmfd
of capacitance as you really tighten down on it.

Now here is the situation on the actual oscillator plate cluster of the tuning condenser, being blind, I would expect it to be, using
an educated guess, of a capacitance value of ~220 mmfd. That condition being when the condenser is fully meshed and of course, that station tuning would be at the very bottom of the BCB.

For the other consideratoin of the tuning condenser, if it was fully unmeshed, the meshed plates would be setting there about no closer than a 1/16 of an inch to each other , that would drop their effective capacitance to maybe only 10 mmfd's of cpacitance.

Of course, that situation would be when you are tuned to the very hi-extreme end of the BCB.

Now really tune in and get my drift from my explicit supplying of the aforementioned info, for the tie in.

Take that tuning condenser and place it at the high end of the band and say it is tuning in a 1700 Kc station and using maybe 20 mmfd of that tuning condensers oscillator sections capacitance . BUT there is an additonal dormant 15 mmfd of capacitance being available on that uncompressed trimmer capacitor, that is in parallel with the osc condenser section and just waiting for you to tighten down on it and also bring its capacitance into play.

Lets see notw if we add up to another full 15 mmfds of capaitance, WOW, that addition could produce a phenomenal shifting of range of that osc frequency's potential operational frequency.

Now lets walk that tuning condenser down to the LOW end of the band and start picking up a 560 station where the tuning condensers osc section might be found meshing up to the ~200 mmfd range there.

Remember that uncompressed C2 trimmer capacitor, crank it down tight now and see the effect that an additonal mere 15 uufd to that 220 mmfd going to have on a frequency swing now.

Make a mental ratiometric comparison of the former 20uufd + an additional 15 uufd .

Now compare to an initial 200 uufd + an additional 15uufd , no comparison on the second situations ratio of change is there ?

Its having a like equal effect as a mouse stepping upon an elephants foot!

Now we get back to the initial statement of:

Radio picks up station(s)very weak (at the) low end of band

Any chance that you are tuned to a weak station down at the 550-700 portion of the band and expecting some great change there, by any adjustment of that C2 trimmer capacitor ?

Normal adjustment of the C2 trimmer is done with the set tuned to a signal generator signal OR a radio station operating on ~1600 Kc.

You trim in C2 for the strongest reception of that signal.

That is done by tuning to that station and then fastly rocking the tuning condenser slightly above and below that frequency while you start slightly adjusting C2. Of course the shifting of the oscillator frequency will be making you have to gradually walk the tuning condenser slowly to the right or left to keep tuned onto that station. What you will then notice is that the reception strength of that station is either getting stronger OR weaker. If getting stronger keep up in the direction of the C2 adjustment, if weaker reverse the direction of the C2 adjustment. At some point there will be a point where your memory says . .HEY .. there was defiinitely better reception in the OTHER direction OF C2'S ADJUSTMENT. . . so you end up with C2 set where the station is coming in the STRONGEST.
What you have accomplished there is optimum tracking . . that is, the tuning of the RF section and the tuning of the oscillator section are optimally producing the very strongest, resultant 455kc signal for the IF strip. In the two other possible continually shifting situations, the oscillator frequency was producing a 454-453-452-451kc frequency or a 456-457-458-459kc I.F. frequency which naturally didn't optimize for maximum gain with those series of tuned circuits in the IF strip that were all peaked on 455 Kc.

Now as per your statement of:

Replaced osc. coil once

Now I think THAT just might be your problem

Would that be an identical Philco oscillator coil, one scavenged from "just " another radio set, or possibly a universal replacement oscillator coil.

I am stopping here for feed back, to see which direction to route further exacting info towards . . .

Aside:

Do you happen to have an old flourescent lamp that uses an iron core ballast . .e.g. desk lamp, aquarium lamp, kids black lite lamp, under the counter GE space saver lamp., etc.

None of the new generation lamps that are using an electronic ballast.

73's de Edd