[Hallicrafters] SX110 receiver

[pato]

Help is needed on the following problem:
I have tunned the sx-110, usung a signal generetor and a
counter, following the original manual. The audio is good
and reception on the high band, 12 -32 Mhz is excellent,
receiving Europe stacions as well as with a modern solid
state receiver. But the problem is that with the antenna
disconnected and the generator set at 14.000 Mhz. an
harmonic is at 15.000 Mhz in both frequencies. I do not seem
to have the same problem in the lower bands.
I will appreciate help and comments , thanks in advance.
Frank WB4EHB