Thread: 3395 AM Filter
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Old February 10th 09, 06:02 AM posted to rec.radio.amateur.boatanchors
Michael Black[_2_] Michael Black[_2_] is offline
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First recorded activity by RadioBanter: Mar 2008
Posts: 618
Default 3395 AM Filter
On Mon, 9 Feb 2009, wrote:

Looking to buy a 3395 AM filter as used in early tube Heathkit
receivers..any other suggestions on receiving AM with homebuilt filter
system? TNX 73 Harold

I thought they stuck with the same IF through the SB line. Or maybe
there was a shift, I seem to recall an article in QST where someone
changed the filter in an early Heathkit SSB transmitter and they had
to make some changes because the then current IF frequency was somewhat
different.

For AM, there's probably a lot more possibilities. Pull some ceramic
filters out of a CB set and cascade them, though those will be at
455KHz. All kinds of cordless phones, cb sets, some older cellphones,
49MHz superheterodyne walkie talkies and other consumer items use
double conversion, with the first IF at 10.7MHz (and a wide ceramic
filter there, the type you find in FM broadcast band receivers) and
then a conversion to 455KHz, so they'd supply the needed crystal
for the second conversion.

If you're not stuck on a specific IF frequency, there's bound to
be still lots of AM bandwidth crystal filters floating around, since
after all relatively few were interested in good filters for AM,
while SSB-width filters were very desired.

Michael VE2BVW

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