I’ve been having a lot of trouble getting on the air with my HAM radios lately. I decided that it was time to buy some more equipment to help make sure that I’m doing things right. Among those tools was an ATU-100 auto-tuner. I was hoping to bring down my SWR and maybe get some decent broadcasts going. An interesting side note though, is that it allowed me to measure my output power.

Turns out, I was only transmitting at less than 1 watt.

Since I’m doing analog SSB communication, 1 watt just isn’t enough. It should be at least 30 times that with my TS-520. So, I started checking my equipment. Fortunately, I have the operator and maintenance manuals for the 520 and the 820. I started by making all the adjustments to make sure nothing was out of kilter, but even so, at best I got 1 watt of output. Using the troubleshooting guide, I went through the steps systematically (the ones I could based on voltmeter or o-scope, since I don’t have all the radio tools). The result was that the final tubes were bad.

So I pulled them out to take a look.

I’m not a tubes expert, but they did have some bad discoloration inside, as if something had burnt up on one side of the glass. Since it seemed likely, I went ahead and ordered new tubes. The originals were Japanese made S2001 tubes, and I couldn’t buy those for a reasonable price. But I found these Chinese made alternates, 6146B’s, instead.

They have a socket, so you simply pop the old ones out and put the new ones in. I was surprised, because I don’t deal with tubes much, I expected to solder something. But for tubes you only solder the sockets in, then put the tubes in the sockets. Which makes sense so you don’t damage the tubes with heat while soldering.

Even better was the result! To God be the glory, it even worked when I was done! Without adjusting a single setting from before (at 1 watt max) I was now getting 28 watts! That’s a phenomenal difference! I was also feeling pretty good about the SWR of 1.29:1 with my new auto-tuner! Maybe now somebody will be able to hear me!

Linux – keep it simple.

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