Hi Mark, Interesting about your MSR2000. I'm not sure about it's band splits but if I'm not mistaken, my MSF is "in band" all the way down to 438mhz. I'm suspicious about my tuning of that 4 pole filter because of my lack of knowledge on the use of a tracking generator. Although, when I was done tuning it, my scope looked very similar to the pics on the MSF page here on Repeater-Builder. I tried tuning it three times and every time I'm done, I only get 70 to 72 watts at the side of the cabinet. OH well....thanks anyway!
Adam N2ACF Mark wrote: > Adam, > > It may be far enough out-of-band for the harmonic filter that it isn't > passing as much RF to the antenna connection port, regardless of what the > specs call for... I had an MSR2000 that was like that - it was in the > commercial UHF band and worked fine, but when it got moved to 444.5500, it > kept burning up the PA - melted the connections to the harmonic filter, even > with silver solder. (We finally gave up on that one.) > > Mark - N9WYS > > -----Original Message----- > From: [email protected] On Behalf Of Adam Feuer > Sent: Friday, May 08, 2009 2:49 PM > To: [email protected] > Subject: Re: [Repeater-Builder] First UHF MSF5000 Attempt > > Hmm??? The book at my friends shop said (if I read it right) that a C74 > with the filter option was rated at 110 from the PA and 85 at the > junction box which is why I'm concerned about my 71 watts. > > > James Delancy wrote: > >> UHF models that are 110 Watts, are rated for that out the side of the >> cabinet. This usually results in 160 Watts out of the PA. Then you >> are down around 100-110 Watts after the harmonic filter and the >> pre/post pass filters. >> >> James >> >> >> Maire-Radios wrote: >> >>> *well if it was 85 watts with 122.5 watts* >>> *it would be lower at 110 watts and any be the 71 watts do the >>> math should be about the same values.* >>> ** >>> *John* >>> ** >>> >>> >>> ----- Original Message ----- >>> *From:* n2acf <mailto:[email protected]> >>> *To:* [email protected] >>> <mailto:[email protected]> >>> *Sent:* Friday, May 08, 2009 2:49 PM >>> *Subject:* [Repeater-Builder] First UHF MSF5000 Attempt >>> >>> Hello All, >>> >>> Attempted to tune up the TX side of a C74CXB today. The odds >>> weren't really in my favor as I've never worked on a UHF MSF nor >>> have I ever used a tracking generator. I brought the station to a >>> friends shop and I used an IFR1200S for the tuning. >>> >>> I checked the station before I began and on 453.900 there was >>> 82.5 watts at the antenna port and 122.5 coming out of the PA. >>> So, I reprogrammed the station, adjusted the VCO, and then began >>> to re-tune the 3 pole and 4 pole filter. I also changed the >>> output power of the PA to 110 watts because I believe that is >>> what the station is rated for. The new TX frequency is 441.950. >>> >>> When I was done with both filters, I checked the power at the >>> antenna port and it's only 71 watts. I believe it's supposed to >>> be 85. >>> >>> The PA looks very clean on the spectrum analyzer and the carrier >>> is right on frequency. Again, I'm not the best at reading the >>> scope while using the tracking generator but I did it the best I >>> could for the first time. Is my output power OK at 71 watts or is >>> something wrong? >>> >>> Thanks in advanced! >>> >>> Adam N2ACF >>> >>> >> >> > > > > ------------------------------------ > > > > Yahoo! Groups Links > > > > No virus found in this incoming message. > Checked by AVG - www.avg.com > Version: 8.5.325 / Virus Database: 270.12.21/2102 - Release Date: 05/08/09 > 11:43:00 > > > > ------------------------------------ > > > > Yahoo! Groups Links > > > > >
