Wednesday, June 10, 2015

WHAT an SWR of 99:9!!

The other evening I had an opportunity to get on the air it has just been to long and I was very excited about spinning the dial around the HF band! I ran the coax out to my MFJ 1788 on the balcony and fired up the K3. I jumped on 20m were not to much was happening but on 30m there was some Dutch DX that was calling CQ so I thought I would give them a go. Prior to calling my SWR on the loop antenna was tuned to 1.2:1 BUT when I started to call the Dutch station my SWR readout on the K3 magically became 99.9:1!!! It was like the coax had been removed from the antenna and was sitting on the ground. It was late so I wanted to look into this at a later time, this evening was the later time so I hooked the antenna up and gave 20m a go and the SWR once again on the K3 was showing 99.9:1. It was time to trouble shoot, was it the coax, MFJ 1788 antenna, the K3 or my LDG antenna switch? The first thing I wanted to do was to remove the antenna as the problem.
Without LDG antenna switch
I removed the coax from the antenna and in it's place put a 50 ohm dummy load. In a way I was relieved to see the 99.9:1 SWR thus removing the MFJ 1788 from the problem. Next I bypassed the LDG antenna switch and low and behold the SWR now was 1.1:1 and me saying thank god it was not my K3! So it would seem the LDG  antenna switch is the problem so I took the switch cover off and looked around. I cleaned the SO-239 connectors, check the internal connections and all seemed to be great. The only problem spot to me could be the switching relays with internal contact troubles? After exercising the relays the trouble in the LDG antenna switch seemed to be ok. If the trouble comes back this is a 4 position switch and I only use 2 positions I could swap out relays and look at ordering all new relays. At this point all seems to be working well but stay tuned to see if relay swapping and ordering is in the near future.
Relay in the LDG antenna switch

Wednesday, June 3, 2015

My memory is good just short!

DSP board version
When I installed my new synthesizer board in my Elecraft K3 I also wanted to take some pictures of the other boards that are in my radio. The reason for this is the K3 has many optional boards that can be added as the operator gets the funds or finds the need to add or upgrade a board. For this reason your rig can have a board with certain versions that go along with it. I have read on the Elecraft site for example a DSP board that is version "C" and above does not need a certain upgrade but the
Filters that are in the K3
boards below that can be improved  with an upgrade. So this begs the question what board do I have??? I really don't want to tear down the K3 just to see the DSP board version. Another example for me is what darn filters did I instal in the K3?? I won't go on and I think you get the idea as to why I took pictures once the K3 was apart. Now having said all this I have on problem that I would like the input from my Elecraft readers. When purchased my K3 I ordered it with  lots of options but since then I have lost the paper work detailing the options I ordered. Most if not all are very easy to see once you open up the rig.... but not the TCXO oscillator. I am not sure if I ordered the upgraded 1 PPM high stability or the stock unit? Below are 2 picture of what's in the rig now your input would be great!
The mystery TCXO

Sunday, May 31, 2015

It's been just too long since my last post!

New Elecraft synthesizer
Old synthesizer board
The time sure has been flying here at VE3WDM! I just can't believe it has been over a month since my last post. I have been off and on the radio more off than on, not sure why other than the evenings seem to get away from me. As for the weekends it's sunny out and the weather has finally changed from snow and cold to nice sunny days with great weather need I say more..........guess what I am saying is Julie and I have been out and about. My last post was when I modified the K3 and since then I also installed the new Synthesizer board as well. I have not even had a chance to really give the new addition to the rig a workout. I have been reading very positive reviews on the Elecraft user group site. I am looking forward to getting on the air and trying this new board out. This weekend the WPX CW contest is on and that would had been a great time to check out how this new and improved synthesizer board improved things!
The board installed in the K3


Sunday, April 12, 2015

Elecraft surgery part 3 of 3

Back to life again
It's time to solder in the new P30 and P35 headers into the K3 then put the rig together hold my breath and plug it in! Now that the old headers are out and the solder pads are cleaned off I now want to fit each header into it's spot and see how they fit. Then I will solder them in and it's very important these headers sit flat on the board. Here is the process I use to solder the headers in, I first only solder the 2 outer most pins. This allows me to reheat the pads if the header is not flat on the board if you solder 4 or more pads at once it's very hard to reheat them if you have to reposition the header. Once I am happy the header is sitting properly on the board I then solder the rest of the pins to the board. I
Soldering end pins 
don't solder them one after the other but instead I solder every other pin and then go back and solder the other pins. I do this because the plastic that supports the pins do get hot. I found if you solder one pin after the next the plastic supports have melted on me. Once the top side has been soldered I then turn the board over and solder the bottom solder pads in the same manner. Now that the pins are in I take a break and then come back and take a very close look at the pins. I am looking for proper soldering job,

Imports of checking both sides of board
also there has been no flow of solder from one pad to the next. Finally that I did solder all the pins, I have had this happen in the past were I have missed a pin. This is why I take the break as I have found if I don't I end up seeing what I want and I miss the unsoldered pin because I want to get to the rig put back together and try it. Satisfied with the solder job its time to clean the solder pads and I use a tooth flossing brush with 99% alcohol. This cleans off any residue and the alcohol evaporates. With the new headers installed it's time to put the rig back together and do the smoke test. At this point it's very important to take your time as you put the rig back together. There is the excitement in getting the rig back together and see how it work! This is the time you forget parts, not tighten parts, rush and misalign parts. Great care has to be taken when mating up the new headers. I had all go together well and as you can see from the picture at the top of the post the smoke test went well.
Flossing tool used to clean board
New header lines up with front board.