03-26-2017, 06:22 PM
I recently finished a complete restoration of a model 70, the early version # 184427. Everything went smoothly. This was a complete rebuild, from the Mershon filters, rebuilding the bakelite blocks, replacing the resistors with a set from Steve Davis, speaker recone and replacement of the volume control with a NOS. The radio played fairly decently. Then I aligned it and the radio really perked up.
One minor problem. We have stations located at 570, 590, 610 and 640 Khz. Below 640, no stations come in. 640 is only 25 miles from me and it too needs to have the volume turned most of the way up. From there up all stations are loud and clear. I only have a 20' wire attached for the aerial. Grounding the chassis didn't help. I rechecked the alignment and was super careful to rock the rotor as I set the 600 Khz trimmer. Nothing changed. I have replaced the oscillator tube 2nd det and 1st IF tube with NOS tubes. No change. Possibly I just need a longer wire antenna, but I doubt it because my 21, with the same wire, works fine at 640.
In 50+ years I have not repaired or restored a model 70. The alignment instructions I was using were off the internet and the paper read Philco Radio & Television Corp., Model Nos. 70 (below ser.#B22,000) Any ideas?
Thanks guys.
One minor problem. We have stations located at 570, 590, 610 and 640 Khz. Below 640, no stations come in. 640 is only 25 miles from me and it too needs to have the volume turned most of the way up. From there up all stations are loud and clear. I only have a 20' wire attached for the aerial. Grounding the chassis didn't help. I rechecked the alignment and was super careful to rock the rotor as I set the 600 Khz trimmer. Nothing changed. I have replaced the oscillator tube 2nd det and 1st IF tube with NOS tubes. No change. Possibly I just need a longer wire antenna, but I doubt it because my 21, with the same wire, works fine at 640.
In 50+ years I have not repaired or restored a model 70. The alignment instructions I was using were off the internet and the paper read Philco Radio & Television Corp., Model Nos. 70 (below ser.#B22,000) Any ideas?
Thanks guys.
