I finally replaced the broken light bulb in my Yaesu G-450C rotator controller

It has been bugging me for a long time, so yesterday I finally decided to do something about it. Several years ago, the illumination lamp in my Yaesu G-450C rotator controller failed. I read some articles online about how to replace the bulb, but was daunted because it seemed a complex job to access the bulb.

The new-look Yaesu G-450C with blue LED fitted. I think it looks great!

17 screws had to be removed to access the 
G-450C bulb.

Yesterday, I plucked up the courage to open the unit and to attempt to at least see what might be involved in replacing the failed bulb.

This required the removal of SEVENTEEN screws. When 13 of the screws had been removed, there was a delicate operation involved in removing the last four, which kept the display plate mounted to the front of the control unit.

Because there were lots of wires connected to this front part, I had to be careful not to pull it away from the unit very much in case I snapped any of the wires.

A short time later, I finally had access to the display plate, and could see the tiny (failed) bulb. I'll be honest and say that at this point, I was feeling quite daunted about my ability to complete this job. However, I decided to go to some local electronic/motor supply stores to see what kind of bulbs they had that could operate on 12V and provided a low wattage (preferably 2w or less). I was able to find a pair of blue LED lights which run on 12V and give out 0.35w.

However, those bulbs were too big to fit in the "holder" where the burnt-out bulb was located. I would have to come up with a solution whereby the new LED bulb would sit in a different location than the old bulb.

The old bulb.

The azimuth indicator display plate.

By carefully snipping some cable ties that kept the small wires bundled together, I was able to get some extra length on the two wires that feed 12V to the bulb. Having done this, it was time to get the soldering iron out for some delicate soldering of the wires to the two copper pins on the LED bulb. I stretched these out, and made a sort-of "hook" on each of them to better support the power wires.

With all that done, I taped up the wires, and began thinking about where I would position the bulb so that it would illuminate the rotator's azimuth indicator. The only place that suited was to the right of the indicator (the original bulb was in the upper-left corner), and with a bit of careful manipulation and some red electrical tape, I was able to fasten the bulb into its new position.

Now I know this might sound silly, but getting the unit back together with 17 screws was by itself a tedious and delicate job. The four screws that hold the azimuth indicator display plate to the front of the controller unit were, in particular, difficult to access - again because I had to be careful not to stretch wires.

The entire job - to replace one small bulb - took me about two hours.

Anyway, eventually I got everything back together and it was time for a quick test. Would it work? I made a short video, which you can watch below.

There's a bit of stray light showing through the 'left' and 'right' switches, but I can live with that. What do you think?

Improvised home brew insulator for my Butternut HF-6V vertical

A number of days ago while operating CW on the 15 metres (21 Mhz) band using 400 watts I turned to look out the window while operating and noticed white arcing sparks coming from a point up the antenna. There was some smoke too. I turned down the power but it was still happening. After stopping transmission I noticed the part of the antenna that was affected was an insulator and I could see from the shack that it was almost burnt out!

The burnt out insulator from the Butternut

So I stopped using the antenna immediately. The Butternut is an important part of the setup here, and a vital antenna in working the world. I planned to take it down and examine it as quickly as possible to see what the damage was.

A couple of evenings later I set to work. I decided to take the antenna apart at a point about six feet off the ground. This prevented me having to disconnect coax and all the stay wires (which are made of strong fishing line). I brought the top part of the antenna down to ground and, sure enough, I could see the insulator was almost melted away in parts.

The new insulator in situ

A few months ago I was gifted a couple of pieces of uPVC that had been cut off a chopping board. You know, one of those things that people chop vegetables and fruit on in the kitchen! Yes, this is where domestic culinary implements meet the hobby of amateur radio. When we say "home brew" in this hobby, we really mean it. If it's made from the right material, it might just end up as part of an antenna! I had been given these bits by Pat EI2HX, with the express purpose of making insulators for antennas if the need ever arose. So thank you Pat!

I set to work cutting away a piece, using a hacksaw, that would  be the same length and width as the burnt out insulator. Needless to say it was thicker, but when I finished with the saw I had a shiny white new insulator. I drilled two holes in it, one for attaching it to the aluminium holder on the antenna, and the other to attach the wire running down the side of the Butternut. After a few minutes of tightening everything up, it was all ready to go back up in the air!

The new insulator

It did look immediately different with the new insulator, but nevertheless appearance does not matter - it's performance that counts! With everything reassembled, the jubilee clip and screws tightened up, and amalgamating and insulating tape added, I was ready to see if it was working.

Some quick testing in the shack revealed that the SWR was still pretty much as it had been, with no ATU in line. I had resonance on the bottom end of 80m (about 1.3:1 at 3.505), and a decent SWR on 40m, 20m, 15m and 10m. I even had decent resonance on 30m! I tuned up the Acom 1000 and put a bit of power into it on 15m, running it for a while. No sign of any arcing - not yet anyhow. 

Given that this particular Butternut is estimated to be at least 20 years old, and that it was resurrected from a very sad state in someone's back garden a couple of years back, it is performing very well. Latest DX worked since the repair was 5N7M in Nigeria on 80 metres CW!