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Old September 7th 08, 06:43 PM posted to rec.radio.amateur.homebrew
raypsi raypsi is offline
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First recorded activity by RadioBanter: Jul 2008
Posts: 242
Default Heterodyne conversion crystals

On Sep 6, 8:31*pm, wrote:
On Sep 2, 4:12 pm, Gary@ removenospamandputkf9cm.com wrote:

I am looking for some Heterodyne conversion crystals for a receiver I am
making.
The frequencies a 5 MHz, 7 MHz, 10.5 MHz, 13.5 MHz, 17.5 MHz and 21.5
MHz.
The variable mixing frequency will be from 3 to 3.5 MHz. I would prefer all
the same type holder.

.

73 de Jim, N2EY


What you ain't got no IF?
All those fine numbers and no IF
You know what the image frequency is with no IF?

I think he can get's 12 and 15 meters.
21.5+3.39=24.89 the bottom of the 12 meter band.
21.5+3.49=24.99 the top of the 12 meter band
17.5+3.5=21.0 the bottom of 15 meters for an extra
squeeze the tuning range to 3.95 and
17.5+3,95 =21.45 the top of the 15 meter band.

Back in the day the reason for Heterodyne was simple
to get a lower frequency at which you could amplify the signal
more readily getting you more SN ratio and selectivity.


73 OM

n8zu