Tag: TH-D7A

Packet, Palm & TH-D7A


Had a fun time interfacing my Palm IIIxe with the D7A. I was able to easily connect to a local digpeater (NASA Langley) and from there the skies the limit. Packet is cool because it reminds me of the old days with my Apple ][ jacking up the phone bill with calls to BBSs outside the local area.


Had a less than successful time with APRS on the Palm. Sometimes from the house I get tons of traffic and other times I can barely get the areas digipeater.

I also hooked up a KVM switch for the two computers that make up my radio room. Had an initial problem with one of the computers that’s running WinME. I had forgotten how much better WinXP is better than WinME – especially with USB devices.

Tomorrow I’m going to try to hook up my Ten-Tec RX-320.

Virginia Beach Hamfest


Went to the Virginia Beach Hamfest today – while it wasn’t super huge, it had the basics. Hearing the old timers on the local repeaters, this Hamfest isn’t what it once was.

I made a total of three purchases:
(1) a spare battery for the D7A from a vendor – PB39M2, 9.6V @ 1450mAh (NiMH). The stock battery is a 9.6V @ 600mAh, so this should be a healthy increase in juice.
(2) a headset for the D7A – MFJ-288. Real comfortable, nice sound. They should work well with my bicycle mobile set up.
(3) and finally a small mag mount 1/4 wave 2m antenna – Workman KS 2-SMA. Intent is to also use this with the bicycle mobile setup.

Tomorrow I want to put the rack on the back of my bike and mount the antenna.

Software for the Palm


I’ve been trying to connect my Palm IIIxe with the D7A and was partially successful.

PocketAPRS is a software application for Palm PDAs – it allows you to interface between a transceiver and a TNC.

The author of the software, Mike (N0QBF), no longer supports the software. I was able to get a copy of the software, but I’m not sure I’m going to be able to register it – which leads me to believe it won’t work properly. We’ll see.

I did get the software loaded onto the Palm IIIxe and was able to get the Palm to talk to the D7A. But as of tonight, I wasn’t able to receive an APRS packet through the D7A and plot to a Norfolk map on the Palm. Maybe tomorrow.

I’m also thinking of getting a fabricated cable to connect the Palm to the D7A:
https://www.bluehillsinnovations.com/store/index.php?action=item&id=17&prevaction=pricelist

Or if I find some software for my Palm T3:
http://www.mobiledriven.com/2tnctopaunca.html

More noodling


I changed my UNPROTO to WIDE3-3,WIDE2-2 and met with some success. The following came off of www.findu.com:

KD7PJQ-6>S7PV8P,N4EVA-11,WIDE3*,WIDE2-2,qAo,W8JUK-3:`h8?o^2″3r}TH-D7A(G)
KD7PJQ-6>S7PV5S,N4EVA-11,WIDE3*,WIDE2-2,qAo,W8JUK-3:`h8Vo6)”4″}TH-D7A(G)
KD7PJQ-6>S7PU1X,N4EVA-11,WIDE3*,WIDE2-2,qAo,W8JUK-3:`h7C!SE”3z}TH-D7A(G)
KD7PJQ-6>S7PT4S,N4EVA-11,WIDE3,K4ROK-10*,WIDE2,qAo,KF4VTT:`h6N!S6″3x}TH-D7A(G)
KD7PJQ-6>S7PS5X,N4EVA-11,WIDE3*,WIDE2-2,qAo,W8JUK-3:`h5(!]9″3x}TH-D7A(G)


Blue dots above represent a plot from each packet that made it to N4EVA-11.

What I did for this test was to connect the GPS to the D7A and drove out to Newport News and back. While going up and down I-64, I kept getting good packets being digipeated from N4EVA-11. But once I leave I-64, the signal from the D7A (with just a rubber duck, no external antenna) no longer hits N4EVA-11.

Unless I set up my own digipeater, I have to be able to get my packet to N4EVA-11. I believe the key piece of being able to do this while bicycle mobile is to install a decent antenna. I’m going to look for something suitable at the Virginia Beach Hamfest this weekend.

More Noodling


Still not quite getting there. I drove out to Langley AFB and parked in an open area. I sparked up the GPS and was soon passing data between the GPS and D7A. The D7A was soon chirping away as the APRS data was inbound. I verified that packets I received were being passed from the D7A to my GPS and plotting as waypoints (as advertised). I then received a beep and the message “My Position” came up on the D7A display. A good sign – this meant that someone had digipeated my packet and I recived it.

So – I know the GPS and the D7A are talking as they are supposed to. But I think my issue is what to use as an UNPROTO path. RELAY,WIDE? WIDE2-2? WIDE3-3? WIDE1-1,WIDE2-1?

Test #1 Follow Up


Yesterday after work I took the bike over to a location with good line of sight, powered up the GPS, connected it to the D7A, and then powered up the D7A. I was receiving APRS traffic and transmitting my position as a beacon. However, I was unable to receive back my packet – so I’m concluding that my signal was not making it to the local digipeater (N4EVA-11). As the D7A is a dual-bander, I left the top band on the APRS freq and the bottom band I set to scan regular local voice repeaters and the placed the D7A in the handlebar bag. On my ride home I could here APRS traffic and a few calls on the regular repeaters, but I could tell reception was poor. I’m assuming having the D7A in the bag greatly diminishes my over all signal strength.

What I have yet to verify is that data being passed from the GPS to the D7A is being xmitted. My earlier test where I successfully passed a packet to the digipeater was from a lat/long location directly programmed into the D7A, not from the GPS.

Right now for a UNPROTO I’m using WIDE3-3. I’m going to change it to RELAY,WIDE and see if that makes it to the digipeater. In the past (with the TinyTrak) I’ve tried using an UNPROTO of N4EVA-11 and then to the Igate. But that’s never worked. I think N4EVA-11 only digipeats RELAY. I’m going to do a little fiddleing around with it this morning.

Bicycle Mobile

My endstate objective is to have a bicycle mobile setup with APRS and packet functionality.

Bicycle Mobile – Test #1

Objective: xmit at least one APRS beacon packet from my bicycle mobile HT to a digipeater capable of ultimately passing the packet to an Igate and enabling anyone to view my location via www.findu.com.

Components used:
(1) Garmin eTrex Vista GPS. I originally got this GPS when I was stationed in Korea back in 2001. While pulling duty in the brigade EOC I overheard radio traffic of a company XO who was making a chow run…. running hot chow out to soldiers in the field. The company XO (a lieutenant) was lost. He didn’t admit it at first, but finally said he didn’t know where he was. Being lost as a lieutenant is pretty bad, but having to admit over the brigade net that you are lost ranks among the most humiliating acts. At that point, I determined I’d purchase a GPS so I’d never be “lost”. I’ve really enjoyed the GPS so far. It worked great in Korea, I also used it in Germany, took it to Kuwait, used it on the convoy into Iraq and Baghdad, used it in and around Baghdad, and also used it on the return trip. It’s very solid and is pretty easy on the batteries. I was previously using the GPS along with my TinyTrack as an APRS beacon (http://www.livejournal.com/users/shedberg/2005/04/21/).
(2) GPS handlebar mount. I received it in the mail yesterday and installed it this morning. Pretty easy to install, the GPS slides on and locks into place.
(3) Kenwood TH-D7A(G). Designed to be used specifically for APRS, I figured the D7A was the radio for the task. I have the stock battery pack (PB-39, 9.6 V, 600mAh). For an antenna, I’m using something similar to the MFJ-1715S. It’s one of those thin, long dual band jobs.
(4) eTrex-Kenwood GPS data cable. I purchased this off of eBay from the GPSGeek store. The cable has the Garmin eTrex proprietary plug on one end and the 2.5mm plug for the radio on the other.

Pre-Test
As a preparatory test last night, I attached the D7A to my 2m/70cm vertical installed on the top of my house. I set the packet path to Wide3-3, manually inserted my lat/long location into the D7A, activated the beacon function and was able to transmit the following packets that made it to the www.findu.com database:
KD7PJQ-6>S7PS8P,WIDE3-1,qAo,N9VP:’h/Vl TH-D7A(G)
KD7PJQ-6>S7PS8P,N3XKU-15*,WIDE3,qAo,KA1UDX-1:’h/Vl TH-D7A(G)
KD7PJQ-6>S7PS8P,N4EVA-11,WIDE3*,qAo,N3IJW:’h/Vl TH-D7A(G)
KD7PJQ-6>S7PS8P,N4EVA-11,WIDE3*,qAo,W8JUK-3:’h/Vl TH-D7A(G)
KD7PJQ-6>S7PS8P,K4EME-3*,WIDE3-1,qAo,N4DSL:’h/Vl TH-D7A(G)


This test confirmed for me that the D7A was capable of transmitting APRS data locally, finding it’s way to an Igate, providing anyone the capability to check my location via the internet.

Test #1 Execution:
This morning I clipped my GPS onto my bikes handlebars and rolled the bike onto the driveway. Turning on the GPS, I was quickly able to get satellite lock and a position read out. I connected the data cable between the GPS and the D7A and powered the D7A on. A Band was already set with the APRS freq and TNC on. I pressed the POS button and the D7A successfully pulled my current location from the GPS and displayed it on the D7A. Immediately after that, the D7A’s red xmit light came on, indicating that the HT was xmiting my current position. The radio beeped and I could see other APRS traffic being received. I locked the key pad and placed the D7A into the bag on the front of my bike with the antenna sticking out at a 45 degree angle.

I headed out on my 5.44 mile trek to work.

The GPS was working fine the entire ride. The speedometer on the GPS was showing the same speed as my little Bell cycling computer.

I arrived at work and pulled the radio out of the bag. There were no stations listed on the screen – which indicates to me that no APRS stations were received by the D7A. I hit the BCON button a few times, but didn’t receive any responses.

I’m assuming one of two things happen: (1) my antenna isn’t doing an adequate job. Again, the D7A is located in the bike bag hanging off my handlebars and I’m not using any type of counterpoise with the antenna. Or (2) there was an issue with how the radio was positioned in the bag which either caused the data cable to come loose or accidentally engaged a key on the key pad.

Test assessment:
Overall the test was a failure.

Recommendations:
Before I head back home after work, I’m going to take my bike over to a location with good line-of-sight and try sending an APRS beacon to see if I’m getting a response. I’m going to first attempt to send the beacon while I’m holding the radio so I can monitor what is being displayed on the screen. If I’m successful with that, I will carefully place the radio into the bike bag and try this test again on my trip home.