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Old 08-21-2011, 10:39 AM
old_coot88 old_coot88 is offline
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I wanted to double check that the tube basing (pinout) shown in the schematic is correct, and indeed it is, as verified here.. http://www.bunkerofdoom.com/tubes/sy...1949/117L7.GIF

After you've gotten that break in the coil fixed, there appears to be a couple of errors in the schematic. It shows pin 8 (cathode) of the pentode section going to ground. I don't believe this is correct. Try ungrounding pin 8.

Now connect lug#1 of the coil to pin 8 (after disconnecting lug#1 from the junction of C5/C6). Be sure lug# 2 connects to ground.

Connect the jct. of C5/C6 to lug# 4 of the coil (lug# 4 should already be connected to pin 3 {plate} of the tube, and to C1 which feeds the antenna).

If the circuit doesn't oscillate, try reversing polarity of either the primary or secondary of the coil (but not both).
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