I will try to! But is difficult to go to the bottom....
Talking about 432 MHZ EME Losses before the preamp are important.
So normally direct at the antenna there is a coaxrelay with high
isolation between te TX and RX port (80dB or so). Preamp is mounted
directly at the antenna and screwed to the relay to prevent losses. I
always used seperate feedlines for RX and TX.
So the coaxrelay provides the isolation. Normally no relays inside the
preamp are used. In Europe the EME HF400 relay is popular with EME-ers.
I am not so familar with the USA relays but Transco is a name often
heard but there will be others for sure!
Preamp & power amp are switched with a decent sequencer and the power
comes via a separate cable, others use the coax.
Have a play with the VK3UM EME calc software, will be a steep learning
curve but will give you a good idea.
Or this article:
I hope this helps...
73 Geert PA3CSG
Op 30-06-2022 om 18:10 schreef wemccourt:
Do these preamps have rf sensing protection, a 12 volt
requirement and are they suitable for outdoors mounting say on antenna
mast or tower leg?
I'm new to this facet of the hobby and just learning my way forward.
Thank you for answering what are, to you, aw probably foolish questions.
Sent from my Verizon, Samsung Galaxy smartphone
-------- Original message --------
From: Geert PA3CSG via Moon-net <moon-net(a)mailman.pe1itr.com>
Date: 6/30/22 11:03 (GMT-05:00)
Subject: [Moon-Net] For sale
I have for sale 2 preamps for 432 MHz with MGF1302 DJ9BV design in a
Noise figure around 0,3dB gain single stage about 19dB
Input is a N type male output is a N type female connector
€35 each plus shipping
Please contact of list.
73 Geert PA3CSG
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