On Tue, 10 Feb 2009, Tim Wescott wrote:


If it's the latter -- well, the same place may have what you want, or you
may be out of luck (did the Heath rigs _have_ an AM selection? Mine
certainly didn't), or you may have to mix to some other frequency (i.e.
455kHz), filter, and mix back. Note that my SB-201 didn't have an AM
detector, either, so it may be more than just a filter that you need.

If they kept the same IF frequency, and I know the SB line did use
something in the 3MHz range, then there was at least one AM filter, for
the shortwave band version of the SB series receiver, the SB-313 or
something.

There was a Heathkit receiver/transmitter set for AM about the time
of their early SSB rigs, same sort of styling as the SSB rig of
the time. The era of the Indian names. I don't know whether those
used a high IF or used the traditional 455KHz, but if it was the
former, they'd surely use the same 3MHz range scheme as the SSB
equpment.

Michael