Update: February, 2004

In this issue:

QRN
Signal/One CX7A
SX-100
DX-60
Antennas
the Internet

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The next issue of Heathstuff.

Join the radio investor discussion group.

--QRN--

  
> 
> I have an S9+ noise level on all the HF bands.  I've suspected my 
> computers, fluorescent lamps, BPL, but I'm not certain.  It 
> sounds/looks like this.
> 
>   
>  XxxxXxxxXxxxXxxxxXxxxXxxxXxxxxXxxxxX
>  0----v----1----v----2----v----3----v----4
> 
> The scale is, oh, 40 meters from 7.0 to 7.4,  each lowercase x is 
> S7-8 pink noise.  Each uppercase X is a roughly 10 kHz wide cluster 
> of shot-noise, S9+.
> 
> The uppercase X's are about 55 kHz apart.   It's all approximate and
> seems to be different at different times.
> 
> I've turned off all the computers and other appliances, alarm 
> clocks, etc.  There is no change in the noise.
> 
> I hear it on all my receivers which include 3 SB-303's and a 
> Signal/One.  
> 
> any ideas?



Depending on where you live, and how dense the housing is, the noise
could easily be coming from your neighbor's gear.
 


The usual culprits for 50 to 100Khz noise are switching power supplies.
They live in TVs, Fax machines, telephone answering machines, battery
chargers, computers, monitors, printers, LED and vacuum fluorescent
clocks, and the biggest supplier of this noise of all, so far, the
compact fluorescent lamp.
 


If you want to check your house for sources of this noise, the easiest
way is to kill all the breakers except for one, and unplug everything
in that circuit except for your receiver.  If you still have the noise,
it is being conducted into your house from elsewhere.
 
-Chuck, WA3UQV

Good info on noise, thanks

I haven't found the source yet.

-- Signal/One CX7A --

I've been working on my Signal/One CX7A. VFO-B wasn't tuning, it felt loose and clicky. I opened the radio and removed the VFO-B module. Three machine screws hold it to the front panel. I was able to remove it by holding my breath and pulling hard. The metal module interferes with other components. The CX7A uses PTO's for VFO tuning.

I opened the module. I had to dress the leads aside. The PTO looks almost homebrew. There is a not very precision wound inductor with a ferrite load that is held by a plastic carrier. The glue had given up and the ferrite load was spinning freely on the threaded shaft.

I used an industrial adhesive, Shoe-Goo, to bind the ferrite load to the carrier. Shoe-Goo is a contact adhesive. It's the same stuff as Goop and other similarly named products.

I reassembled the PTO, ran it hanging loose to verify that the PTO was tuning. I measured the voltages with the TDS-210, one channel on PTO-A and the other on PTO-B. Close. The output voltage on PTO-B was a little lower, about 10% but it sounded fine.

The CX7A is now working with both PTO's. Add $200 to the value. I need to pick the crystals for the spare sockets.

There is a problem with AM reception. I have the AM filter and AM stations sound good but I can hear the CX7A's BFO. Don't know why that is.

I plugged my Brown Brother's paddle into the CX7A. It's wired backward from the way I wired my old kit TTL IAMBIC memory keyer. These used to be a standard of hamfests along with DVM kits, digital clocks, and counter kits. Don't see too many of those any more.

The S/1's keyer works. Not only does it work but the QSK is VERY nice. Wish the sidetone volume was on the front and not the back.

Of course, I don't know how much of the transmitter is working. The 8072 was replaced by a 4CX350F and there are wires hanging out the back. I hope this doesn't mean that the power transformer is bad.

I listened to the S/1 with an SB-303. It sounds very nice. Pure DC note.

Keyer works, QSK works. It's looking pretty good. I might be able to get the Signal/One CX7A working 100%. Wouldn't that be fun.

Here's the plan. As time permits and as parts and information come my way, I'll refurb and fix the old radios. I believe that these old classics will become valuable collectables in time and that we are at the low point in the price cycle.

I really cannot understand many of the items that people collect, Hummels, baseball cards, the pots and lamps of bygone eras. Most of these things just sit there. They collect dust and look stupid.

Boatanchors are precision products from an age that will never, ever come again. An SB-303 was $389 at a time that a Chevrolet Corvette was $3,890 or there abouts. OK, the 1970 Corvette was a little more.

A Signal/One was roughly half the price of a Corvette.

NCR made about 1,000 Signal/One's of all types.

Here're some big differences between a boatanchor and a Corvette, ceramic pot, or a stupid "antique" table.

I can fire up the CX7A (or SB-102 or HT-37) and tell the world, "The rig here is an SB-401 driving an SB-200 to 550 watts output, hows the signal?"

Then I can mail a QSL card with a picture of my boatanchor station. I can put the picture on the web and be tres-cool.

Even if I don't feel like talking or pounding brass, I can take a few minutes to tune across the band, "Ah there are a couple QSOs going. Sure sounds nice on the old SB-303.

Sure sounds nice.

I've seen folk who have antiques, weird brick-a-brack, why do they have them. I saw part of that "antique roadshow", some furniture dealer was gushing over a "gen-U-wine" something or other antique chest. Well, I have a radial arm saw, power plane, router, and a power sander. I could make something close to that. Make it look close enough to fool most people. A radial arm saw turns a wood butcher into a cabinate maker, or so the story goes.

I could not make an SB-102, ever. I could not make something looks like an SB-102. I could certainly not make something that works like an SB-102. I can make ceramic pots. Anyone with a little practice can make a "looks like" most of the junque that people call antiques or collectables. Don't get me started on all the counterfit, signed "game balls".

Then I got into it with a guitar collector. Guitar collecting is big, but why? Most people can't play well enough to keep people from running away. It's a guitar. OK? What are you going to do with it? Sit there strumming it? Yodeling like a cowboy. That's fun? Well, some folk might enjoy that. A guitar is worth something because a model like that one was used by Elvis? How much is a toilet seat that looks like the one that Elvis died on?

Come on. These boatanchors are valuable because they work and all there ever will be, exists now. As the ham population grows, the price will double and double again. Why are vibroplex and J-38's so expensive? They are a part of history and each of us knows the tactile sensation.

What am I going to do with an SB-104A? I can work the world. I can listen to geezers on 75 meters harangue each other. I can send CW and listen to code with an SB-104A.

December 2003, bought a Be block, socket, sub-assembly, and heatsink for the CX7A though the Signal/One list on QTH.net. Have discussed 8072's with a land mobile specialist. It looks like I'll have the parts to get the CX7A working. The question is the power transformer and power supply. Can I get the right voltages for the 8072?

== SX-100 ==

December 2003.

I was looking at the electronic BBS at my jobsite, "Free radios, if no one wants these, they go to the dump."

The list included an SX-100!!!!!

It took me about 30 seconds to send an email to the fellow, "Yes! I'll take it."

I picked it up. It's almost flawless in appearance. The fellow owned it since the 1970's, used it until a year ago. He gave me a xerox of the manual and the instruction sheets for the digital display kit. The docs were in a folder along with a xerox of the radio shack ad for Hallicrafters.

He pointed out the SO-239 that he added to the back. Hallicrafters drilled the back panel for one but didn't mount a coax connector.

His SO-239 is connected to the counter/display.

This is a choice radio. I don't know why he decided to dump it.

He had it in a cardboard box along with the accessories and the manuals. As I was leaving, he said, "if you decide you don't want it and toss it in a dumpster, please don't tell me that you did that."

I assured him that the SX-100 would have an honored place on my radio shelf (next to the S/1) and that when it came time for me to pass it on, it would go to a good home.

I noticed normal, minor scuffs, and suspect that two smaller knobs might not be "factory". If they are not, they are the closest I've seen to matching.

The external digital display is from the Feb 1977 Popular Electronics and was a board-kit sold by Mattis Electronics of Morton Grove, IL.

The radio is a cosmetic 8+, some minor dents and scuff marks, good knobs except one tuning knob is missing a "bright" insert and the two small notch knobs might be substitutions. They look really good though.

I did a search for SX-100 and knobs and found a bunch of folk looking for "orginal" notch knobs. This tells me that my "substitution" knobs are orginals. I'm guessing that Hallicrafters did a run with uncalibrated knobs and over the years, folk have assumed that these knobs are subs.

You SX-100 owners, if you have notch knobs that look a little funny, no 50, 51, kHz marks, I bet those are factory knobs, just from a rare production run, probably adds $100 to the value of your radio. Or not.

I'm afraid to put power to it until I can get a small Variac. The owner suggested that I bring up the voltage slowly to let the electrolytics reform.

I'm still pinching myself. I looked up SX-100's on eBay and AADE and these average $300. Some have sold for much more, up to $800.

This radio will increase in value over the years. Dachis' Hallicrafters book says that these are plentiful but still, the info packet included a Xerox of a Radio Shack catalog, penciled in "1962", the price of the SX-100 was $325. I was 16 years old in 1962 and remember that radio in the catalogs.

A coke was 10 cents, a 1962 Corvette was $2995, and movies were 50 cents. This radio was more than 1/10th the cost of a Corvette!

One surprise. It uses the same three round pin AC cord as the Heathkit SB-303's. That cord is hard to find. He gave me the cord. It fits my SB-303 but is about twice as heavy-duty. He also gave me a Lafayette speaker for communications receivers, it's in a metal box.

I flipped all the switches and turned all the knobs. It feels good. The gear-drive, flywheel tuning is smooth. The dial cord is a steel cable.

All the tubes are there. The 100 KC crystal is in the socket.

The front panel is a weird chrome finish with a black diamond imprint overlay There are a couple scuff marks and, maybe, a half dozen black diamonds are scraped off.

The flip lid is tight and the finish is good. There are two or three small dents, smaller than dime size. I think I can "roll" them out.

The other stuff he gave away were some Mac computers, piles of magazines, and a WWII radar scanning receiver. He had modules for up to 1 gHz. The scanning was done mechanically by a motor. He said that the scanning receiver was used on battleships.

I realize that I'm going on and on and am on the verge of nattering but this is an amazing day and there interesting aspects to this. Someone, said that we don't own these radios. They come into our lives and we can enjoy them, fix them but that at some point, it is time to pass them on to someone else. This might be a swap, an outright sale, or in this case, the fellow wanted to just pass it on to a good home.

I have DX-60 (which needs work), it'll be a nice match for the SX-100. The SX-100 has a 500 Hz selectivity position, tunable notch filter, and a pitch control (BFO). Very nice early 1960's CW station.

Man-o-man, what a day. My pals Betti and John took me to lunch for my birthday after I picked up the radio. Does it get better than this?

I built up my courage to put power to the SX-100. I hooked up 50 feet of wire to the antenna terminal, connected a RS Minimus speaker. Turned it on.

Wow!!! It works great.

I have my reference SB-303 (the one with the dual 2.1 filters) connected to a parallel 50 feet of wire.

I calibrated the bandspread for 80 meters, tuned around. Stations sound GREAT. It sounds like my old SX-101A. Big tube audio. Gentle rolloff on the filters so you can hear QSO's up 6, 7 kHz and down a little as "artifacts" superimposed on the audio.

Opposite sideband supression is good, not great, just like the SX-101A. I played with copying sideband with different filters.

I listened to a geezer-net on 3.950 mHz. One of the stations was weak but he was weak on the SB-303 too. From a cold start the SX-100 could hold an SSB QSO for several minutes.

I tuned down to the bottom of 80, copied some CW, tried the different filters. Not bad. I never liked the harsh sound of a 200 Hz mechanical filter. The Heathkit 500 Hz filter makes the tone too high pitched for my taste.   The SX-100 is better.  

My assessment based on tuning around is that the SX-100 is as competant a receiver as any. A pal just got an ICOM IC-756 Pro II. He's already complaining about the modes, menus, and small knobs and buttons.

--DX-60 --

November 2003. I adopted a guarenteed dead DX-60 from eBay. As long as the meter and the power transformer are good, I'll get it working as a low-tech crystal controlled station along with an SB-303. I'm guessing that the DX-60 was guarenteed dead because the seller did not know about the fused plug that Heath used. There were no fuses in the plug.

 Push come to shove, the DX-60 and a couple rocks plus the SX-100 would make the ultimate SKN radio. Good for Classic Exchange CW too.

=========== QSL ===========
AH6GI/4
XMTR: Heathkit DX-60 90 Watts.
RCVR: Hallicrafters SX-100 and Heathkit SB-303
XCVR: Signal/One CX7A
AMP: Heathkit SB-200 with Harbach mods
TNX QSO, UR RST
CW, Date Time
===========================

-- Antennas --

I've "gotten into it" with some Hams on how "terrific" their multi-thousand dollar DSP, computerized rigs are. Well, they're not that much better than a good boatanchor. When you tell them that, it's like you're telling them that they wasted their money.

In the audio world, there are "tube-nuts" with golden ears who can hear the thickness of the speaker cables and the plating on the connectors.

Strangely, the same hallucination in the Ham world are those who think they can hear their synthesized rigs not drifting. They can hear the smoothness of a DSP passband compared to the peaks in 6 and 8 pole crystal and mechanical filters.

You can't blame them, radio ads are crafted to convince them to spend thousands of dollars on new radios. A good quality boatanchor will run with the big dogs. A KWS-1 and a 75A-4 will haul freight as well as the newest most expensive ICOM, Yaesu, or Kenwood. The converse is true too. The cheapest ICOM, Tentec, Elecraft, works as well as an SX-115 and HT-32B.

There are things that matter.

A good QTH with high ground conductivity and a clear shot to the horizon, that's important. Almost as important is a directional antenna, 4 elements wide-spaced at 80 feet is much better than a bent dipole strung to a nearby tree.

I have an old TH3jr. Katashi Nose, KH6IJ, told me that you can run 500 watts or more to a TH3jr. That a 3 element tribander at 40 feet was the minimum "good enough" antenna for working DX.

Another possibility might be a 2 element multiband cubical quad. The 2 element cubical quad is interesting because the same geometry should support 10, 12, 15, 17, and 20, 5 bands with one rotary antenna and one feedline. Good gain, good frontal lobe, low angle of radiation.

Boatanchors. Good enough. Retro. And if the loonies who stare gap-jawed at those Antique Road TeeVee shows ever figure out what these things are, a Heathkit DX-60 will be $5,000 and a Hammarlund HQ-180 will be $30,000.

-- The Internet --

Some folk have wondered why Ham Radio when there is the Internet and cell fones. Come on, people. Why climb mountains, ride horses, sail, when you can sit there slack-jawed and wonder what became of your life. Why hike across country or scuba dive when you can sit in a bar and get sloshed?

Why build and race a AA-Fuel Dragster or a world land speed record car? Why do anything when you can play a video game, hour after hour?

Why refurb and operate a classic tube radio transmitter when you can whip out the Mastercard and buy Japan's finest which has terrific specs?

You know why. If you're wondering how the story of the SX-100 or the Signal/One CX7A or the DX-60 will unfold, you know. Will I get the DX-60 working? Is there anything wrong with it? You're reading this, not because I'm a great writer but because you have a curiosity in you. You want to know how the story unfolds and what is in that box.  This curiosity and intellectual inquisitiveness is the why of Ham Radio.   It's more fun when it's not easy.   Boatanchors are a challenge.