Where did you buy the Mitrek rx preamp? ----- Original Message ----- From: "johnmichaelwelton" <[EMAIL PROTECTED]> To: <[email protected]> Sent: Saturday, May 21, 2005 9:23 AM Subject: [Repeater-Builder] Re: Poor Repeater RX
> Alexander, > > Motorola makes a preamp for their T43-T83 Mitreks that is inserted > after some filtering on the front end. May be a better way to > implement a rx preamp in your setup, and they're pretty cheap, bought > a few recently for $25/each. Also, I agree with Glenn that separating > the Mitrek decks into separate receive and transmit rather than doing > the duplex mod is a much better approach for 2M on the Mitrek. > > John/N4SJW > > > --- In [email protected], "Alexander Tubonjic" > <[EMAIL PROTECTED]> wrote: >> Hello, >> Well here is one that cant be figured out locally, thought I would >> throw it to the experts. My high school radio club has recently > made a >> few upgrades to our VHF repeater. We replaced the Ringo Ranger > antenna >> with a Comet GP-9 Antenna, replaced the 9913 coax with Andrews 1/2'' >> Heliax, and put a Mirage Pream inline. The problem we are having is >> mainly with the preamp (I think) >> I will describe the setup and give all the specs first. The > repeater >> Rx and Tx is from a 110 Watt Motorola Mitrek power out from the > Mitrek >> is 50 watts. The power supply is an Astron RS-70M, Duplexer is a >> Sinclair Q202G (yes, it is properly tuned and working as it should) >> the antenna is rooftop on the schools theater building (the roof is >> about 75 feet AGL and the antenna is on an 8' mast pipe) there are > no >> obstructions for at least 5 miles around. The preamp setup is as >> follows, it is after the duplexers and before the reciever. We have >> the preamp directly connected into the duplexer and a jumper going >> from the preamp to the Rx bulkhead on the repeater cabinet. The > preamp >> has two settings, a higher gain and a lower gain setting, initially > we >> had it setup to the higher gain setting but I went up today and >> switched over to lower gain and turned the power output to 30 watts. >> The problem we have is the Rx is not what is should be. It is a > tad >> worse then when we were running the repeater at 15 watts without the >> Preamp. I would really like to get the preamp to work like it should >> in the repeater system, I just dont have any ideas on what to do > next >> to get better sensitivity on the machine. Any thoughts and ideas > would >> be appreciated. Thanks. >> Alexander KG4OGN >> >> P.s, all jumpers are made with double shielded ridgid coax, so > thats >> not the cause of the problem. > > > > > > > > Yahoo! Groups Links > > > > > > > > > > _____________________________________________________ > This message scanned for viruses by CoreComm > > Yahoo! Groups Links <*> To visit your group on the web, go to: http://groups.yahoo.com/group/Repeater-Builder/ <*> To unsubscribe from this group, send an email to: [EMAIL PROTECTED] <*> Your use of Yahoo! Groups is subject to: http://docs.yahoo.com/info/terms/
