05-07-2013, 09:14 PM
Sometimes I wonder if Philco just used whatever parts they had on hand any particular day.
It reminds me of the tube shields on the 80B. I have seen both aluminum shields and larger plated steel shields used on the mixer/osc tube. But now I have run across an example of an 80B that has a small aluminum shield on the mixer/osc and a larger steel shield on the detector in the same radio, even though both tubes are type 36.
Perhaps there is a reason in the case of the 38-116. The 6U7G tube is identical to the earlier 57 and 6D6 in that there is no internal shield surrounding the plate, only a circular shield under the grid cap. Perhaps they had troubles with oscillation with the square shield and found that they had to go to the earlier type of shield specific to the 6U7G which narrows at the top .
It reminds me of the tube shields on the 80B. I have seen both aluminum shields and larger plated steel shields used on the mixer/osc tube. But now I have run across an example of an 80B that has a small aluminum shield on the mixer/osc and a larger steel shield on the detector in the same radio, even though both tubes are type 36.
Perhaps there is a reason in the case of the 38-116. The 6U7G tube is identical to the earlier 57 and 6D6 in that there is no internal shield surrounding the plate, only a circular shield under the grid cap. Perhaps they had troubles with oscillation with the square shield and found that they had to go to the earlier type of shield specific to the 6U7G which narrows at the top .
