Kevin, Now that I understand what you are trying to do, be advised that just because you have the link RXs co-located with the comparator your remote site Link transmitters do not have to transmit all the time. Just an FYI. I started to do exactly what you are attempting with the comparator but it just was not worth my time to modify it make it work when I had the other recievers available to me at the right price. I have all the manuals and my prints of the mods (including the SRN-1068) which make this comparator actually vote the best reciever properly, if you need them. Also have the factory mod sheets for the receivers as well if you decide to go that way.
Dan -----Original Message----- From: [email protected] [mailto:[EMAIL PROTECTED] Behalf Of Kevin Custer Sent: Thursday, January 19, 2006 10:58 AM To: [email protected] Subject: Re: [Repeater-Builder] Operating a Spectra-TAC Comparator (Voter) without RX encoders. Hi Dan, Thanks for the response, but I'm looking for someone that has modified the comparator for use outside the Motorola Spectra TAC environment that has done away withe the need of continuous links and a status tone (modified it for COS input) manually adjusted the AGC, but still utilize most of the functionality of it. My linkback equipment is flat from 45 cycles to 5.5 kHz and I have receivers at the repeater site that have a widened I-F to capture all of the noise bandwidth I can get. The remote receivers are Hamtronics R144's that have been modified for better squelch action. They feed Hamtronics TA-451 exciters that have been retro fitted with a direct FM modulator. Audio recovered from the receivers discriminator is buffered, limited, and filtered at 5.5 kHz and fed directly to the FM modulator. The deviation is set to a 5 to 4 ratio to preserve the headroom. The linkback receivers are Hamtronics R451's that have had some of the crystal filters removed and a slightly wider 455 I-F filter replacing the original quite narrow one. Kevin Dan Babilla wrote: >HI Kevin, > >I use Spectra TAC Revievers (such as the C04RTB3108) as Link RXs stack at >the same site as the Comparator and I directly wire them in within the same >cabinet. In working on systems with these type of voting systems for many >customers in the 80's -early 90's, I have found that the levels between >receivers are very critical as are the levels between the audio and the >status tone. Everything needs to be exactly the same for the Spectra Tac >comparator to properly vote the best reciever signal. > >For best results use all the same remote recievers as well. Make sure the >audio response of all reciever paths are adjusted the same, I use an OP amp >circuits to tailor all audio down links to be completely flat across the >link. I'm sure you already do that though. > >73's, > >Dan KA0OXH > > >-----Original Message----- >From: [email protected] >[mailto:[EMAIL PROTECTED] Behalf Of Kevin Custer >Sent: Wednesday, January 18, 2006 9:06 PM >To: Repeater Builder; Micor List >Subject: [Repeater-Builder] Operating a Spectra-TAC Comparator (Voter) >without RX encoders. > > >Hi, > >Need some opinions from folks that may be using the (newer) Motorola >Spectra TAC Comparator as a stand alone voter, using RF links that don't >transmit all the time. I have some theories on what to do, but I >thought I would post to see what others have done. > >Please be as specific as you can. The comparator I have is the newer >style that uses Signal Quality Modules that produce a voltage that >corresponds with the quality of the signal received, not the 3 Micor >squelch chips. > >Thanks in advance, >Kevin Custer W3KKC > Yahoo! Groups Links 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/
