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By Larry Higgins, W5EX

Digipeater Installed at Brackettville

WX5II-4 is on air at the Intertie/Border Amateur Radio Society site at Brackettville. This joint effort finally took off on Saturday, December 6, with KD5FVZ installing the new Sinclair SRL 235 antenna, K5DRT and N5VRP pulling on the rope, while W5EX hooked it all up. K5ZZT donated the power supply, K5MCA the radio, N0VH the 1270 and firm/software.
 

Reviews of QST

KISS Mode TNC (John Hansen, W2FS, QST, Nov. 2000).
I built John's TNC. Works fine - likes 1200 Baud best. Seems like errors creep in as the baud is increased. Needs to be set at 4800 to work with GPS.

Software Choice

We are running UI-View 32 here, with Precision Mapping maps. Working on the transistor toggle to allow GPS on demand by the CPU RTS line. ("Hardware single port switch - [HSP]). Schematic and instructions are imbedded in UI-View Help. Press F1, after selecting "GPS Set-up" in "Setup". Bench check of circuit done: works! More checks in progress.

Hardware Choice
If this works out, John's circuit can be programmed like a Tiny-Trak -or - used in KISS mode with UI-View. That way, you can still be tracked without the computer, with GPS connected.
I want to see if the HSP can be kept in line with the 2 modes. If not, no big deal: just hook the GPS to the TNC line and feed the satellite data for tracking.

This ought to give the best of both worlds

Leave lap- top home: Program "APRS " into John's KISS TNC:>Pure tracker, like TT-3 (I haven't tried this yet)
Bring lap top: Tracks you on map - and - all APRS traffic received - on the map. Requires HSP.
So far, I have been unable to make John's splitter work as shown in QST. So, GPS + Kiss TNC + Laptop is a no go with UI-View, or his recommended program: - Win APRS.
 

Correct FM deviation

Keep deviation 2.5 KHz nominal for the combination of 2 tones in Tiny-Trac setup program, or by watching your beacon's deviation on a service monitor 'scope. I think that most of the non-processable packets I see in terminal mode could be over-deviated. Just and opinion!
We are going to take a look at KC5EVE's wav. files at http://www.com/mark/radio/packet/radio.

Terminal mode is a great place to trouble-shoot receiving difficulties

Weirdest junque is seen when conditions are really poor. Lots of SA1xxx calls > 800 miles range. You may be able to use your Windows Hyperterminal program. Click on Programs>Accessories>Communications>Hyperterminal. [Make a shortcut to your desk top]. Configure to use Com 1, or whatever serial com port you are using, then set baud, word size, parity, stop bits. With 1270 use 9600 7E1 or 8E1; With UI-View use whatever your TNC is set for - usually 4800 8N1. Use this program to configure Hansen's KISS TNC, or to monitor incoming traffic.
Correct APRS unproto address. I'm working on this. I'm close.
Cable recommendations. Stay tuned. You need to settle on a standard cable configuration, with colors assigned. This will prevent many wasted hours with pesky serial data ports.

Home GPS, using MFJ 1270

With N0VH's help I have configured a 1270 for Host NONE, Handshake NONE, 1296 Baud, 8-bit, Even parity, 1 Stop bit. There is a pre-programmed button for TNC-2, which is what a 1270 is - which pops up when you select NONE for host. When you boot the program, with the 1270 already on, you will see UI-View program the 1270. Cool!
1270 outperforms the Hansen KISS unit - fewer errors, more stations decoded.
Set toggle switch 6 up - the middle of 3 "radio" switches at the back of unit. These are the last 3 switches. The previous 5 are for baud set -- toggle 5 up. Do this with TNC OFF.
I found that the 1270 does not like 4800 baud. Also, in UI-View "Setup" is a category of "Miscellaneous". In there, you can decrease digital selectivity for address and QTH. Needed for sure with the KISS TNC.

Time waster. Like all digital stuff, this can be a voracious parasite on your available free time. We hope to publish here things no else seems to get down on paper. Comments to us appreciated: Email W5EX

W5EX
Copyright 12/03
Work in progress

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Revised: 01/01/05 05:28 PM by N5VRP, Dennis Rogers, Webmaster
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