[Collins] 75S3-B is receiving different bands

[Osamu Hazawa]

Hello All,

My 75S3-B seems to receive different bands, other than normal bands.

1. No modification but SB_2 has been made (by me).
2. It occurs on 7MHz band and above.
3. It occurs when the preselector indicates about half position it should.
4. e.g. on 21.4MHz position, the preselector is set at about 5, it receives
    BBC and Radio Australia on the same band. They seem to be of 21.660MHz 
and 21.725MHz.
5. CAL tone is heard at different position it should (30kHz away from the 
tone).

Of course, it receives very good on normal bands with proper preselector 
position.
Yes, I'm very happy with that situation but very curious.
Could this happen logically?

73's
Osamu