RadioBanter - View Single Post

Lostgallifreyan · October 28th 14, 10:24 PM posted to rec.radio.amateur.antenna

wrote in :

As for the output voltage, you do know FET input opamps work quite
well at 60 Khz and are dirt cheap?

Which is one reason I mentioned the CA3140. :0 But there is a huge voltage
gain too, with the hyeteresis (positive feedback) and the ability to get a
single rail supply working well for direct interfacing to a digital input.
I'm not sure if that is what rickman means when he says ;digital receiver',
but if I'm right in assuming he's after MSF time signals, this direct input
to a digital IC is a technique often used, I was talking about it to someone
just last week, but we didn't discuss anything to do with antennas. One thing
I forgot to mention in the earlier post is to AC couple the input. An earlier
gain stage might be needed too, but nothing you can't do with a single
CA3240E. Next step uo might be LT1215, but not needed, the speed of CA3240 is
plenty. Easily good for 200 KHz with fairly good pulse shapes.