Things that are happening

Trying to break out of the mold where I sit in front of a computer all weekend getting nothing or not much done.  I have wasted an enormous amount of time doing this for quite some time for numerous reasons I'm not going to bore you with.

Last week to prepare for a trip to the Ft Wayne Hamfest I actually hard mounted the control head of my Kenwood TH-D710A to the dashboard of my truck.

Don't worry, I bought a replacement plastic bezel on eBay so if I need to restore the vehicle before it's totally junk, I can do so.

For years I used AVMAP Geosat GPS's to drive the Kenwood radio.  AVMAP partnered with Kenwood writing code for their GPS's enabling the call sign's of received stations to be displayed on the moving map display.  I thought this was way cool and bought the Geosat 4.  Got a Geosat 5 when it came out and then a Geosat 6.  Lotsa bells and whistles but compared to the Garmin gps's the AVMAP's just suck.  After 3 models and more than 1200 bucks spent I decided to go simple.  I never use all the neat features anyway.  So I bought a Green Light Labs GPS-710 which glues to the back of the TM-D710A's control panel.  So for best performance you gotta get the gps where it can see the sky.

The other issue with the AVMAP GPS and the TM-D710A, they never seemed to work all the time.  I attributed that to my inability to get the programming right so both units could talk correctly to each other.
I wanted something that JUST WORKS.  So a week ago Thursday I installed the GPS-710 and mounted the control head.  Looked nice but IT DIDN'T WORK!   I wanted this to work for my trip to Ft. Wayne.  I don't drive much (thank goodness) and everytime I go on a trip I seem to be fiddling to get the GPS/TM-D710A working.  I doesn't work and I resolve to fix it some time.  A time that never comes and now after spending more money I have something that didn't work.

I was sure there was some kind of firmware problem with the radio.  The radio has firmware, the control head has firmware as well as the TNC that's in the control head.  And Kenwood occasionally puts out user installable updates.  I was sure I messed it up the last time about a year ago.  Checking the Kenwood site I saw a control head update I didn't have.  The next problem was finding the cable that connects the radio to the pc.  That process took days sifting thru boxes of stuff packed away a year ago during a cleaning spree.  Finally found the cable and applied the updates.  STILL DIDN'T WORK.  Now I'm trashing Kenwood cause they can't make a radio the works.  One good thing is that I was getting very familiar with the menu tree in the radio and can breeze thru it without helper documents.

I set the radio to beep when my position was transmitted and turned on SmartBeaconing.  Every time I turned a corner the beep would go off but no transmit.  It was like the PTT from the TNC was not connected somehow.  I thought the PTT was part of the data stream between the control head and radio.  Or perhaps there was some TNC command got overwritten by a wild write or something.

One thing that bugged me during the install was the cable that connects the head to the radio had a flaw.  The jacket of the cable no longer was clamped inside the RJ45 connector.  I didn't think too much about it other than it looked like shit and someone or some process failed to build a good cable and that cable was on my radio.  It got me thinking though....   The TNC (in the control head) tells the radio when to transmit.  The TNC was trying to transmit cause I was hearing the beep.  What if the PTT was a discrete signal on the cable?  What if the conductor was one that was stressed where the jacket worked free.  SHIT !  I tried another cable and, IT WORKED!!!  every time I hit the BCON button the radio would transmit.

After another search I found my crimping stuff, crimped a new RJ45 onto the cable and put it all together.  So now look for WB8CXO-9 on aprs.fi       FWIW

NOTE:  The problems I had with the AVMAP GPS's were, in my case, inability to program and troubleshoot a systematic problem.  The folks at AVMAP put a lot of effort working APRS into their product.  I have always been treated well by the AVMAP folks here in the states.  Don, W6GPS does a great job supporting the AVMAP/Kenwood products.  Not all products are for all folks.  I look forward to seeing what the next device brings to the APRS function.

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FOCUS...  One of the problems when you're drowning in 40 years of collected junk is you find stuff from your past that is forgotten about.  So this weekend while searching for the Kenwood programing cable I came across a box that contained my Heath GC-1000 Most Accurate Clock.

All my geek friends had one.  I built mine in the 80's and used it to keep my PC clock on time.  I love clocks that are self setting and ACCURATE. I also found the spare front end transistors I bought cause the receiver in my clock went deaf.  So I thought.  I wonder if this clock will power up?  It did and the receiver was mostly dead.  Seeing the front panel function brought back the excitement I once had for this device.  I had another GC-1000 somewhere that I bought off of Ebay many years ago.  Easily (for a change) I found it and plugged it in.  Receiver worked but it would not decode data.   Well my old GC-1000 decoded data so I swapped receivers.  Now we're decoding data and in about 15 minutes the clock when HI SPEC!  But in my case, NOTHING IS SIMPLE and comes with a long story.

The GC-1000 RUNS HOT!  All the electronics take the whole 1 amp output of the 7805 which is an inefficient linear voltage regulator.  The transformer also runs hot.  Jeff Thomas from Resonant Instruments created a web site that discussed the heat issues with the GC-1000.  http://www.amug.org/~jthomas/gc1000.html
So perhaps 5 years ago mabey longer I bought a PT5101N Integrated Switching Regulator module and all the electrolytic caps and modified my clock per Jeff's suggestions.  Removed these parts:

Installed the switching regulator and new electrolytics:

You can see above where the circuit board is discolored by the heat from the 7805 and it's heat sink just below the blue electrolytics.  In my case the regulator worked fine but as with my luck there were associated issues.  There is a little circuit board that mounts on top of the 7805 heat sink.  With the heat sink removed there is no natural mounting for this board.  First thought was just let it float or wrap it in tape.  Tacky...  Found some 4-40 stand-offs and mounted the board wondering why the solution escaped my when I originally replaced the 7805.

Here's the inside view of the GC-1000.  The orphaned circuit board can be seen to the right next to the blue electrolytics.   Pics used here on my blog were taken from Jeff's site.... Thank You Jeff, it was so much easier than taking my clock apart to take my own pics.  So now I have a working cool running GC-1000 that keeps accurate time.

Now for the REST OF THE STORY....
Put the clock in service and started to write a blog (this was a few days ago).  I looked up at the clock to see if it had locked into HI SPEC.  The clock was dead....  Apparently the metal standoffs that I used to mount the little circuit board had shorted the 5 vdc line from the regulator.  Reworked the standoffs with some nylon washers and got the clock back.  It's always something.


Overall it was a good weekend.  At least I got some things done. In spite of the time it took to blog!  Now to drag myself over to the workbench to build............  LVB TRACKERS.........