I've been doing some clean up on the filter unit for the Kenwood TS-430S HF radio. Some bands were not working and the filter unit was suspect. I had already tried the prescribed 12 V DC current treatment without any changes on the bands that weren't working. I noticed several bad joints and manually disassembled each relay and checked its operation. At least two of them were not making good connections and required cleaning with some contact cleaner and a dollar bill. After this cleaning they seem to be working. I also noticed several bad solder joints. Here is some photos of the board.
After doing some initial testing on the Kenwood TS-430S project cleaning up the IF board issues I had been getting 100 watts on some of the bands. Suddenly last night during a test I noticed the radio would begin clicking and resetting. After a bit of head scratching and doublechecking power going into the radio I finally traced it down. The molex connector at the rear wasn't making a good connection. I used some needle nose pliers and some deoxit and solved the problem. A quick fix to a problem is always good.
07/14/2011 - After removing the IF board from the TS-430 I could see some issues right off hand. The top site of the board was realitivly clean although I noticed some excess thermal compound on the regulators which gave me a hint that this IF board had been repaired at some point. Getting it out I could see lots of oxidation, burn traces at one of the regulators and at least one connect that had ripped the traces from the board. Tonight I cleaned up much of the board tested all the diodes on the rear of the board, and repaired the 5V traces. At this point the radio seems to work but I don't have very good recieve and it still only transmits on some bands. On the bands it does transmit on it does full output which is a good sign. I'll be working on the IF board for the next few days as its in bad shape on the rear side.
07/18/2011 - Well thus far, I have replaced the traces on the 5V regulator with jumpers as the eyelets were missing and that area of the board wasn't in very good shape. I also located a burnt or gouged trace which will need repair. A missing eyelet was found on Connector 10 and I ended up glueing the connector to the board and replacing the trace with a wire. After looking at the board from the top I've noticed several missing caps. I expect someone has tried to repair this board and during checking cold solder joints they may of pushed the caps off the board without noticing.
07/19/2011 The gouged trace has been repaired. Now the IF section seems to be working at least a stage or two away from the audio section. I ended up with a TX issue which was a bad connection at the molex connector which slowed progress on the IF board issues.
05/02/2011 07:12 AM - The order for the 1.0D board has been processed and passed design checks with manufacture. We all should see boards from the group buy in the next 3-4 weeks hopefully. Parts have already arrived. I'll be posting more information and documentation during those long 3-4 weeks of waiting here. I recommend to everyone to use an AVR platform for MCU development an interface but you are welcome to use what you want. The goal is to end up with something that is under the 100ma current of the MIC interface. Read more...
I've done a test layout to play with that I'll be testing in the next few days. Below is the layout.
Several folks have asked about using Arduinio hardware with APRS TNC. I don't have a lot of motivation but figured I'd get the project started. If you have an arduinio and would like to help develop this using arduino hardware please post (no emails please). Here is the alpha schematic I'm working on using the display I started with in the original design.
I've gotten ton's of emails (100 or so) about the code for the APRS node I've been hacking away at. I normally use an Arduino type board for prototyping. However, the code is in C. I do sometimes use processing to quick test something but generally things destined for the embedded world are in C. Below are some projects I found related to what I am working on. Some use the CML chips some don't. In the low cost model I don't use it. I have been playing with a CML chip for digital type radios but they drive the cost up with what I am attempting to do which is build a device within the reach of just about any public safety department in volume. And please if you don't mind, post questions as comments rather than emailing me directly. That ensures that any Q&A can be seen by everyone.
http://garydion.com/projects/whereavr/ - This is a really nice setup, different application but very tidy setup.
http://sites.google.com/site/ki4mcw/Home/arduino-tnc - Hope to see more from this. Its what more of you are looking for with PDE files provided.
I've used the radio quite a bit during the last day or so and I've already got a list of things the radio could do but doesn't. Its a great radio and just a few of these features would make it top notch on usability and flexibility. Below is what I have so far. Feel free to comment!!! ....
Recently I purchased a Wouxun KG-UVD1P radio. My main reason was that it was a inexpensive radio that was part 90 certified and had VHF UHF Dual band including HAM bands. Construction is great and it appears to be just as rugged if not more so than my TK-3180 and TK-380. ...
AX.25 encode is complete and seems to work well. AX.25 decode works, but I have a special mode and also have a CTCSS listen setup to remotely turn on that mode. Still some items to do , but its almost time to put this on a board. If you are interested in this project please let me know. I was able to get my Brother Laser printer to work with the toner transfer method after some trial and error. I had great results using a Brother HL-4070CDW and Kodak inkjet photo paper using a iron and being very patient with the soak.