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The instructions we have (see the second figure in post number 20) do call for
adjusting the oscillator at two points with both the trimmer cap and the coil.
The manufacturer may have dropped the adjustable coil in production, in which
case the oscillator would be aligned only at the high end of the band, and
some error would have to be tolerated at the low end.
Typically, you will find a hole in the chassis above the coil so the tuning tool
can be inserted from the top. Do you see the hole?
Note regarding the alignment instructions: I don't see any contradictions.
Items 1 to 3 refer to the IF alignment (which can be left out). Items 4, 5 and 6
are the steps for aligning the oscillator to get the stations on the right
spots, with 7 telling you to repeat 5 and 6. Finally item 8 is the peaking of
the input circuit resonator, using the trimmer on the RF section of the variable
capacitor, that is the section that is NOT part of the oscillator circuit. Regards.
P.P.S.: the variable capacitor section for the oscillator may be bigger or smaller
than the RF section, depending on the coil used. Tracing the leads to the proper
circuit (and also checking the labels C1/C2 on the alignment drawing) is the
best way to determine which section is which.
Last edited by electroking; 07-22-2010 at 12:44 PM.
Reason: added note
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