Agree all points, Jerry.
Why I used 4007 back to back?
I put the darn thing together in a pinch to add in an external RX antenna.
The 4007 were the only thing I had with me.
The diodes were not used for switching, just for clipping.
In other rigs I have used reed relays, keyed by the internal "T" signal to
switch out before the juice came.
I don't understand why so many folks make such a big deal out of the missing
RX antenna.
I have added this to more rigs than I can count.
It's about the simplest mod one can make.
73
Rick
-----Original Message-----
From: tentec-bounces@contesting.com [mailto:tentec-bounces@contesting.com]
On Behalf Of Dr. Gerald N. Johnson
Sent: Tuesday, October 12, 2010 8:03 PM
To: tentec@contesting.com
Subject: Re: [TenTec] Is The Eagle really soaring yet?.
Why the 1N4007? They are poor PIN diodes and too slow to be protective
diodes. If you want strong signal protection you need much faster
diodes, 1N4454 or 1N914 derivatives. If you do RF switching with the
diodes you need real PIN diodes to keep down intermod. For that matter
back to back protective diodes are serious receiver intermod causes.
73, Jerry, K0CQ
On 10/12/2010 7:15 PM, Rick - NJ0IP / DJ0IP wrote:
> If you don't run an amp, all you need is an RCA Phono Jack or BNC on the
> back panel, a simple toggle switch on the back panel, and a pair of 1n4007
> diodes. Less than $10. If amp, I would add in a reed relay to switch the
> RX ant to ground during TX.
>
>
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