Yep - I see the same as you, Eric. That's why I continue to wonder about these cards.
I originally bought 14 chassis altogether, and was provided with about 9 of the same Master Decoder card. In the beginning - the world was dark and without form... sorry I digress. In the beginning, I got the chassis and cards from a purveyor who had them stacked in the corner of his place. Can't vouch for where they came from, or if they were even assembled and working prior to that (some of them were already victims of parts scavengers) and to be honest, I can't remember if he did, either. So since the very start I've been operating on the assumption that these cards worked in the chassis I have -- probably an incorrect assumption, I'm beginning to believe. However, the bigger problem is NOBODY seems to be responding as to whether they have either the later version cards OR the schematic for the cards I have. Until I can confirm something (one way or another) I'm at an impasse. Mark - N9WYS -----Original Message----- From: Repeater-Builder@yahoogroups.com On Behalf Of Eric Lemmon Mark, Now, I'm the one who is confused! I just looked at a UHF community repeater and noticed that it has a TRN6421APR backplane. However, it is equipped with a TRN6165A Master Decoder. I therefore wonder if the TLN5803A Master Decoder you have even belongs to that machine. I confirmed, as you did, that Pin 24 on the TRN6165A Master Decoder has no connection. Is it possible that the previous owner simply stuffed the chassis with leftover pull-outs? The TRN6421APR backplane PCB has the following module assignments, right to left: 1 - Timeout Timer 2 - Station Control 3 - Squelch Gate 4 - Single Tone Decoder 5 - Master Decoder 6 - Four-User Control 7 - Ditto 8 - Ditto 9 - Ditto 10 - Diode Logic 11 - Multi-TPL Encoder 12 - Multi DPL Encoder I have no manuals for a Community Repeater, so I do not have any means to follow the signal path via schematics. That said, it seems to me that a "Multi-TPL Encoder" in Slot 11 would generate the unique PL tone that the repeater would transmit. You did not state if such a module was installed in your station, so I wonder if that is why your station is not encoding the tone. As others have noted, it is always preferable to filter out and then regenerate a PL tone, rather than allow it to pass through a repeater. The reason for that is two-fold: Some cheap user radios have very poor tone purity, and may be difficult to decode, and some user radios have widely-varying tone deviation that range from not enough to double or triple the "proper" level. 73, Eric Lemmon WB6FLY -----Original Message----- From: Repeater-Builder@yahoogroups.com [mailto:[EMAIL PROTECTED] On Behalf Of n9wys Sent: Sunday, September 21, 2008 9:04 AM To: Repeater-Builder@yahoogroups.com Subject: RE: [Repeater-Builder] Update on the MICOR Community Repeater project Eric, --- (snip) --- At one point in the build, I *thought* I had this problem resolved... but apparently what was happening was the PL was bleeding through from the receive to the transmitter. That is why I was able to "talk it off". After looking at the station operation with a service monitor, I am certain that it is NOT encoding PL for transmit. I have no PL at Pin 2 of the Master Decoder, which is what feeds the PL tone to the exciter/modulator. For everyone: At one point, Eric referred me to an eBay auction, listing among other things a Master Decoder card of the same part number as the ones I have. Those cards were in an MSY chassis... which makes me wonder if there is a fundamental difference on the MSY-version versus the MICOR-version of this card. My examination of the card leads me to believe this is the case, I just need to verify this. Eric, the part number stamped on the backplane is: TRN6421A, and the number on the Master Decoder card is: TLN5803A Thanks everyone! Mark - N9WYS / WQIV271
