I am working on a Realistic (Radio Shack) HTX-100.  I purchased two of these for $45 last May, and was told “one works, one does not”.  I joined the HTX-HF_Tech Yahoo group and started looking into things.

The initial problem (but not the ONLY problem) was that there was a lot of static noise from the speaker.  This noise was internal to the radio (thanks to a troubleshooting tip I got on Google+ that told me to short the antenna center to shield at the back of the radio).

I started poking around at things, and found that a trimmer resistor was dirty and was causing the static.  Combined with the fact that the speaker was desoldered from the board (an oh-so-difficult fix!), I thought maybe I fixed it.

Then I hooked it up to an antenna and checked its ability to receive.  Nothing.  I could tune stations in on one HTX (and on my Ten-Tec), but not on this one.  In fact, I couldn’t tune anything.

One of the things available (not only on the group but also from a few additional websites) is a repair manual, which is really very helpful.  I started into the alignment procedure and noticed that in step 3, I was nowhere near the target value of 10.695 Mhz, and was not able to adjust to get anywhere close.  So I started looking at the troubleshooting section for the PLL board (where the coil in step 3 was located).  A few steps in the process, I checked voltages on one of the ICs and found a handful of them off.  I started checking further, and questioned a crystal.  I replaced the crystal and found no change.  So, I started looking at other things.  I checked the voltages on other ICs and found a handful of others that are off.  I looked at capacitors, and noticed a few that have tears that seem to indicate that they’ve failed.  I replaced one that I happen to have, and it fixed one of the voltages on one of the ICs.  Progress!  I have a few more to do, but I need to order the parts.

Blown Capacitors on the HTX-100 PLL Board

Main Board of HTX-100

PLL Board of HTX-100

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I’ve had a few “duuuh!” moments recently:

• I tried to test SWR with the mic on SSB without whistling or saying “heelllllllooooo” (I realized I shoulda known better and got a 3.5mm plug to use as a redneck key)
• I saw something on the Internet about using a butane torch to solder PL-259 plugs.  One of those plugs just popped off the wire it was supposed to be soldered to.  Another had the center insulator shorted to ground.  Each time I’ve done this, I’ve burned insulation and other stuff.
• I got my work computer banned from http://www.hamqsl.com/solar.html trying to make a Rainmeter skin for it.  Fortunately, I did this on Friday and the ban was lifted by Monday.

I’ve had a few smarter moments, too:

• Since I bought a pair of the HTX-100s, I joined the Yahoo Group and just started watching messages.  A recent message by another group member indicated that the display would be back if you let a certain capacitor charge.  The supposedly-broken rig is now working again.
• I joined the Milford Amateur Radio Club.
• I started playing with MPM Morse Factory on my Android phone to practice sending in CW. Unfortunately, it appears that it has disappeared off the Play Store.
• I wanted to see Ham Nation on a big screen, so I used my Blu-Ray player to pull it up on YouTube.
• I dropped by a truck stop on my way home from a meeting in Frankfort, KY to grab lunch.  While I was there, I browsed through the CB aisle and picked up some RG-8.  Probably not the greatest stuff, but it’ll work in the pinch I’m in.