Friday, September 18, 2015

The Venerable TS-430S

The Venerable TS-430S with AT-250 antenna tuner.
I realized earlier this week that my backup rig, the Kenwood TS-430S, turns 30 years old this month. Yup, I bought that rig back in September of 1985. For the next 16+ years, it would be my only HF rig.   I held on to that rig so long, by 1995, I was already calling it "venerable."

How I got to that point is an interesting story. My original Novice setup was an SB-301/SB-401 combo. In my second or third year of college, I sold my SB-401 to my brother Ben (now NJ8J). I still had the SB-301, and eventually I set it up in one of my college apartments. But I lacked a transmitter.

One summer, I attempted to rebuild my Novice transmitter using a 6GK6 and 6146 design published in the ARRL handbook. I added a lot of extras, like a built-in VFO and a KOX (key-operated-switch), with automatic T/R switching. (the VFO and KOX board were salvaged from a home-brew 40m QRP rig project that I assembled, but never could get to work) I never could get any output from that 6146 rig, and it chirped pretty badly.

Shortly after I finished college and moved into an apartment, I borrowed a friends FT-101E. The rig worked great. Because of my crummy antenna situation, I had a lot of trouble making contacts. Eventually my friend asked for his FT-101E back.

Since he bought the SB-401, my brother wasn't using a Heathkit DX-60B he had, so I borrowed it. I pulled the VFO out of the Novice transmitter, mounted it in a box with the KOX circuit board, a power supply and connectors for the DX-60B. This actually worked! I made a handful of contacts, but again the antenna situation really limited me.

In the summer of 1985, I moved to a new apartment much closer to work. It was two stories tall, and there were a number of trees about 30 feet away from the back. I took a couple of 100 foot spools of #26 wire wrap wire and strung them into the trees from my second-floor shack window, fed from the back of a crappy MFJ tuner with a balun. This formed a crude doublet.

For an operating table, I bought a door, placed it on two short two-drawer filing cabinets, and finished it with stain and polyurethane. I did a good job, because this door is still my operating table to this day in Gwinnett county.

I still needed a rig. I decided I didn't want to fool with tube-type radios any more. (That urge would return later) I wanted something that was all solid-state, had a direct-reading frequency display, supported the new WARC bands, and didn't cost terribly much.

At that time, the top contenders were the Kenwood TS-430S and the Yaesu FT-757GX. Both had a reasonable feature set, and were similarly priced around $600. I don't know what tipped me toward the Kenwood. In retrospect, based on what I know today, the FT-757GX had more features -- it does full QSK and has a built-in keyer, as well as supporting computer control via the CAT system. Computer control would be something I would pine for a few years later when I got into contesting.

Back in 1985, I wanted to get the best deal on my TS-430S, and I must have called a dozen different dealers for a price quote. The deal I found was a TS-430S for about $630, including the optional FM board. I placed the order with my credit card -- and this was perhaps the first time I would go into debt for my hobby.

I didn't do a lot of operating from that apartment, but I did enjoy the TS-430S. The crude doublet actually worked pretty well. I spent a fair amount of time on 30m, which was a relatively new back then, but I also hung out around the Novice bands on 80, 40 and 15m.

I moved to a house in Stone Mountain, GA, and the TS-430S was my main rig. My antennas progressed from a 300 long wire to a loop skywire, to a 125 foot doublet, eventually complemented by a Butternut HF4B beam on a roof tower that eventually gave way to a Cushcraft A3S. I started contesting in 1986 with CW Sweepstakes. The TS-430S paved the way for a whole lot of radio experience for me.

As a rig, the TS-430S is not a bad performer. There are two key deficiencies that were fixed by it's successor, the TS-440S: a) computer control, b) 100% duty cycle. The TS-440S adds a host of other features (100 memories, internal antenna tuner, selectable filter bandwidths, FSK, selectable AGC) Ironically, the TS-440S would be introduced at Dayton in 1986, just a few months after I bought the TS-430S.

CW performance is reasonable, depending on your expectations. There is no QSK, but the VOX operation from the key is quick and reliable. You can at least listen between words. AGC action is fast. The 500 Hz CW filter is a must-have.

SSB works well. VOX is fully adjustable, and the speech processor produces reasonable results on air. Choosing LSB or USB, though selects the slow AGC, which is annoyingly sluggish.

FM is interesting. I played around with 10m FM in the late 80s. There used to be a few guys in the Atlanta area that would hang out there back then. I think it may have faded, along with a lot of 2m FM.

Receiver performance is pretty good considering the up-conversion design and the vintage. There's certainly some front-end IMD, which you hear as a "sparkle" sound, especially on 10m when it is open during a contest. Usually hitting the attenuator knocks that out. The notch filter is pretty good, provided you are only dealing with one carrier. Of course, you have to adjust it manually. Noise blanker is one of the better ones.

Some contesters would be displeased with the manually-centered RIT. Never bothered me. IF Shift can sometimes help fight QRM -- but not in really crowded conditions.

This rig has some features I have rarely used. General Coverage Receive is one of them. Program scan has got to be the most useless of all -- since you have to manually hold the scan if you hear a signal.

I have made a handful of mods to my TS-430S. I did the 10 Hz frequency readout right away. (Why they didn't ship it from the factory this way, I'll never understand) Back when I used transverters for 2m, I enabled all-frequency transmit. Oh, and I did a simple mod that allows the YK-88C 500 Hz CW filter to be used for SSB narrow. This is useless for Phone, but makes easy work for RTTY.

Running RTTY is a mixed blessing. With the 500 Hz filter and the IF Shift adjusted, it does respectably on receive. The slow AGC is a little bit of a problem. Transmitting, though, should be limited to about 50-75 watts. Be sure to turn off the speech processor.

This rig has been with me at five different QTHs, as well as a host of Field Day operations. Although I long ago bought an MB-430 mobile mount bracket, I have never mounted it in a mobile.

Considering all the rapid changes in electronic and radio equipment in the late 70s to mid-80s, what with the transition from tubes to transistors to integrated circuits, plus the addition of new amateur bands -- it is amazing this rig still holds its own. I certainly didn't expect to be using it 30 years later.

Wednesday, September 9, 2015

BAM! - AL-80A Broken Again

Well, crap. The AL-80A is broken again. Yup. I was on 17m chasing a bit of DX, when I decided I needed more than 100 watts. I hit the A->B button, then A/B, then tuned a bit away from the DX frequency (never tune up on DX - ever), dialed in 50 watts, switched the amp to operate and hit the Tune button.

Heard something go POP! as I turned the plate tuning knob, and immediately the grid current meter pegged. Not good.

A little diagnoses -- with no RF, keying the amplifier the grid current meter reads about 100 mA. Even with about 20 watts, the grid current meter pegs. Seeing the output meter peg, too.

At the worst, I may have fried my tube. I suspect I may have blown more of the metering circuitry.

This amplifier is very picky about 17m....