Tim,
My plan at this point is to convert them to full duplex, so I can use the
second Mitrek to prepare a complete, plug-in, standby set of RF decks. The mods
look very straightforward, but I was wondering if there were any gremlins
people discovered.
Your heatsink approach, however, is exactly what I was talking about. I have
several very large heatsinks originally designed for use with big SCR switching
circuits which look to be more than generous for a 30w PA at 100% duty cycle.
My first repeater was built from a 2w Repco exciter board repurposed from RFID
service. It was supposedly rated for continuous duty, but had to run very hot
to dump the heat it produced through the little aluminum tab mounted to its own
PC board within the case. I fashioned a new tab with a 90ยบ twist which allows
sinking the little PA to the case itself, and it never got above "warm to the
touch," even after hours key-down.
Guys, I appreciate all the input.
73,
Paul, AE4KR
----- Original Message -----
From: w7...@comcast.net
To: Repeater-Builder@yahoogroups.com
Sent: Monday, April 26, 2010 10:16 AM
Subject: Re: [Repeater-Builder] Mitreks as UHF Repeaters?
Isn't the rpt. going to be built using (2) Mitrex, thus shielding should not
be a problem. I have, in the past (with the help of a Bridgeport mill),
fashioned "Larger Heatsinks", that bolt onto the orig. Mitrex heat
sink....seems to dissipate heat well...
