The front-end tuned circuits add to the selectivity and "sharpness", if you will. Sure the set picks up station off the top of the 24 tube, but the extra tuned circuit ahead if it keeps the unwanted signals, hetrodynes and images from being amplified by the tube.
Chuck
The antenna coil improves selectivity. It's a tuned circuit. Actually in the Philco 90, it's a double tuned circuit. Without it several stations nearby on the dial may be heard at the same time.
Yes, connecting an antenna to the 1st RF stage, top cap, will pick up stations. If connecting an antenna to the proper terminal doesn't work a coil may be open?
Norm
:Hello, I am not sure of the exact need for an antenna coil. If I can touch the grid cap of the first 24 tube and get reception, then why does the radio have an antenna coil, two tuning caps, and a 1st I.F transformer coil. Couldnt the 24 tube be biased accordingly and have the antenna signal fed directly into it? of course I am not an engineer here so there's gotta be a reason for that stuff.
Sean, you wouldnt be asking that question unless there was a problem. One of the coils is open, either the antenna coil or the oscillator coil, and I suspect the oscillator coil. You can get a strong station by doing that!! Check the continuity of the terminals with the wires off. (make sure to color code before doing)
::Hi Sean
::
:: The antenna coil improves selectivity. It's a tuned circuit. Actually in the Philco 90, it's a double tuned circuit. Without it several stations nearby on the dial may be heard at the same time.
::
:: Yes, connecting an antenna to the 1st RF stage, top cap, will pick up stations. If connecting an antenna to the proper terminal doesn't work a coil may be open?
::
::Norm
::
:: :Hello, I am not sure of the exact need for an antenna coil. If I can touch the grid cap of the first 24 tube and get reception, then why does the radio have an antenna coil, two tuning caps, and a 1st I.F transformer coil. Couldnt the 24 tube be biased accordingly and have the antenna signal fed directly into it? of course I am not an engineer here so there's gotta be a reason for that stuff.
:
:
:Sean, you wouldnt be asking that question unless there was a problem. One of the coils is open, either the antenna coil or the oscillator coil, and I suspect the oscillator coil. You can get a strong station by doing that!! Check the continuity of the terminals with the wires off. (make sure to color code before doing)
:Hello, I have tested the antenna primary coil with "continuity also and it shows no connection. Is continuity check better or recommended so the coil will not be overloaded?
:
:::Hi Sean
:::
::: The antenna coil improves selectivity. It's a tuned circuit. Actually in the Philco 90, it's a double tuned circuit. Without it several stations nearby on the dial may be heard at the same time.
:::
::: Yes, connecting an antenna to the 1st RF stage, top cap, will pick up stations. If connecting an antenna to the proper terminal doesn't work a coil may be open?
:::
:::Norm
:::
::: :Hello, I am not sure of the exact need for an antenna coil. If I can touch the grid cap of the first 24 tube and get reception, then why does the radio have an antenna coil, two tuning caps, and a 1st I.F transformer coil. Couldnt the 24 tube be biased accordingly and have the antenna signal fed directly into it? of course I am not an engineer here so there's gotta be a reason for that stuff.
::
::
::Sean, you wouldnt be asking that question unless there was a problem. One of the coils is open, either the antenna coil or the oscillator coil, and I suspect the oscillator coil. You can get a strong station by doing that!! Check the continuity of the terminals with the wires off. (make sure to color code before doing)