Mark, Saw your post about RTCM and Garmin 18LVC. If your Garmin is fairly new, it's quite possible you've run into the same problem as I did. Garmin changed the specs on the unit and *didn't* update any docs. The 1 PPS line coming from the new units is only 3 volts instead of 5 Volts. The RTCM is expecting 5 Volts. It is possible to modify your RTCM to accept the 3 volts, however, I still had trouble with this after the mod and never could get it working reliably. A better solution is to just use a GPS that puts out the correct levels. I am looking at moving to Symmetricom/Furano units. They can be had cheap, are already designed to be mounted outside, are RS422/RS485 outputs so can be run long distance, and are way more hardy than the little garmin puck. One little RS422->TTL converter inside, with a buffer driver behind it and you can run many RTCMs off the single GPS signal coming in. If you are installing at a repeater site, they are seem to be a good alternative to the Garmin, and are way cheaper than the Trimble. Hope that helps. 73 James KI0KN ---------- Forwarded message ---------- From: <app_rpt-users-request@ohnosec.org> Date: Wed, Mar 30, 2016 at 9:26 AM Subject: App_rpt-users Digest, Vol 85, Issue 52 To: app_rpt-users@ohnosec.org Send App_rpt-users mailing list submissions to app_rpt-users@ohnosec.org To subscribe or unsubscribe via the World Wide Web, visit http://ohnosec.org/cgi-bin/mailman/listinfo/app_rpt-users or, via email, send a message with subject or body 'help' to app_rpt-users-request@ohnosec.org You can reach the person managing the list at app_rpt-users-owner@ohnosec.org When replying, please edit your Subject line so it is more specific than "Re: Contents of App_rpt-users digest..." Today's Topics: 1. Re: Garmin GPS 18 LVC RTCM wiring (Mark DuMoulin @ WB2ERS) 2. Re: Garmin GPS 18 LVC RTCM wiring (Skyler F) 3. Re: Non-RTCM voter, where? (Joe Leikhim) 4. Re: Non-RTCM voter, where? (Jeff Ackerman) ---------------------------------------------------------------------- Message: 1 Date: Tue, 29 Mar 2016 20:41:32 +0000 From: "Mark DuMoulin @ WB2ERS" <wb2ers@metcom.com> To: "electricity440@gmail.com" <electricity440@gmail.com> Cc: "app_rpt-users@ohnosec.org" <app_rpt-users@ohnosec.org>, Tim Sawyer <tisawyer@gmail.com> Subject: Re: [App_rpt-users] Garmin GPS 18 LVC RTCM wiring Message-ID: <cde8aeb0edee46229c60c0f689178b3f@MAIL2.metcom.com> Content-Type: text/plain; charset="us-ascii" Skyler, Good afternoon. I saw your post regarding the RTCM-GPS-18x LVC question. I would use the app_rpt site but cannot seem to get registered. I have tried many times to get registered on the app_rpt users but it always comes back no such user!!! Here's the question: I have two of the same RTCM and Garmin GPS 18x LVC. I have been completely unable to get either to work. I followed your wiring: RTCM GPS 18x LVC 6 GRX <-- Rx Data 6 Green 7 GPPS <-- Pulse Output 1 Yellow 8 GND Ground 3 Black 8 GND Ground 5 Black 13 +5V -->Vin 2 Red 14 GTX --> TX Data 4 White No joy. Did you get yours working? Anything you can share? I have a feeling that the Garmin's have been reprogrammed to something other than factory default 4800 in the PGRMF. Tnx, Mark DuMoulin Sr. WB2ERS 800-410-3130