K5LAD - 50+ Years of Ham Radio Memories

Volume XXX

Don't Hold Your Breath That Long

= You're Turning Blue

Painfully pulled from the memory of Jim Pickett – K5LAD

 Back in the 60s in the Tulsa area, the popular thing in the VHF neighborhood was the introduction of FM operations and repeaters in the 2 Meter band.  The 2-meter repeater that started it all in this area was the WA5LVT machine on 146.34/146.94 and it was one of the pioneer machines, at least in this area of the U.S.  It was originated in, as I recall, the early 1960s.  My first introduction to the “Loud Voice of Tulsa,” was in 1964 not long after we had gotten married.  I've previously written about my first experiences in the 2-meter FM world and how I was pretty much unable to afford one of the nice rigs that several of the other guys had.  The equipment being used was older Motorola, GE, and a few RCA rigs as these were pieces that had seen service in the law enforcement, fire service, taxi, and other assorted service industries.   As time progressed and the need for more frequencies became evident, the law required commercial radios to be upgraded or replaced with those using narrower modulation, although it was still FM.   Many of these older units were given up and sold for the amateur radio service that had a more relaxed requirement on modulation width.  As long as this mode was up in the higher frequencies available to hams they were fine, since nobody had much need for them at that time (key phrase - "at that time").  Some of these radios included the receiver, the transmitter, and the mobile power supply were all constructed into a solid steel rectangular container which could be installed in a remote spot in the vehicle, usually in the trunk area.  The radio would be attached to a large umbilical cable assortment which included heavy power cable to attach to the vehicle's battery, a thick multi-wire cable that ran to the interior of the vehicle, which included connections for a microphone, a speaker, often several lamps, and wires for switching between a few different frequencies.  There would also be a place on the primary unit to attach to the mobile antenna.  Most of the power supplies were for either a 6 or 12-volt connection, depending on what type of vehicle would house the radio.  To generate the high voltages required for TX and RX strips required either a vibrator or a dynamotor unit.  I realize that these terms might envision an entirely different picture to someone from a younger generation so perhaps I should define the terms. 

 All these radios were tube-types as the transistor, and later the IC eras, were still in the future.  All of these tubes required a higher voltage, typically in the 200 to 300 volt range, for RX and TX and the transmitters needed even a higher potential.   Since the only voltage available in the vehicles was generally 6 or 12 volts DC; that was insufficient for the tubes.  To raise the voltages to what was needed required a way to convert the DC to AC, which would then work through a transformer, and that conversion was accomplished by a mechanical chopper device, the vibrator, which did the job while buzzing like a hive of bees.  The dynamotor was for the higher voltages and was essentially a motor and a generator that shared a common rotor and shaft.  The vibrator generally ran constantly, any time the radio was turned on but the dynamotor only ran on transmit when the higher voltages were required.  Both of these power supplies required many amps of current but the dynamotor often pulled so much current that the vehicle's lights would dim when transmitting.  This is why the power leads from battery to the radio were often very heavy and bulky.

Early in the 1970s several ham radio manufacturing companies decided there was money to be made in building ham-specific transceivers using transistors.  Transistors had first been invented in 1947 but by the 70s, the demand had become so great for the features they offered that tremendous research had gone into developing newer and better transistors.  Each new group of transistors would have greater gain, operate at much higher frequencies, incorporate smaller packages, and demonstrate many more ways for their use.  Not only could they save space, heat, have much lower power requirements, and many other things but also the prices had come down easily within the reach of the average John Q. Public and particularly, Joe A. Ham.  They were said to be essentially indestructible since they had no filament to burn out.  Of course, hams, as well as many other users, proved them wrong since they could be destroyed quicker than you could say, "Ooooops."  With much care, however, they could be long-life devices

CK-722 transistor.jpg (37039 bytes)

  I remember a research paper I did as a senior in high school (1959) that was on a bright blue rectangular shaped transistor designated, the CK-722.  This PNP transistor, made by Raytheon, could be bought for 99 cents for a single device and was ideal for hobbyists, experimenters and hams.  The transistor was not silicon, as were later transistors, but was made of germanium and could amplify up to something like 600 KC (what you'd call 600 KHz today).  That's not very high but it was a great piece to work with and was well within the budget of hams.  It could also run on a flashlight battery in a time when most electronics experimentation required a high voltage power supply as well as a filament supply.   The frequency went high enough for audio, some low frequency RF, and operational applications like as a meter amplifier, etc.  The CK-722 is an interesting story but one for another day.

Back to the early transistorized ham rigs (beginning in the 70s), it's interesting how the popularity of these radios came about locally.  The first one I had a chance to sell was the Inoue IC-2F, built by the company who later was to be called ICOM.  This was, as I recall, a 6 TX, 6 RX, 10-watt transceiver and was a really nice radio -- probably ahead of its time.  The first one I remember that I sold at Derrick Electronics was to a ham who was a sales representative who drove around to various nearby states, as well as around Oklahoma. He was buying a new car and thought one of those IC-2Fs would sure look nice in it.  He had the automobile dealer contact me and I sold the dealer the radio.  The dealer installed the rig and included the IC-2F in the price of the vehicle and it was just another accessory to be paid for as part of the monthly car payment.

Some of the other early day transistorized rigs included one made by WRL (the Galaxy FM-210); a 3 frequency TX and 3 freq. RX, 5-watt FM rig.  Other rigs came from Clegg, Simpson, S.B.E., Drake, and several others.  In an infant industry, the thought had not occurred to the designers that an ideal radio should have plenty of places for receive crystals but more (even twice as many) transmit positions since many hams preferred to have both a repeat and a direct TX provision for a single receive frequency.  Each, of course, required a separate crystal.  Typically, most of these radios came standard with one RX and one TX crystal, both on 146.94 MHz.  If there was only one repeater or just a bit of simplex operation in a particular geographical area, it was usually on 146.940.  Some people had a bunch of frequencies available but EVERYBODY had “.94”

By far one of the most popular of these transceivers, in this area, was the Regency HR-2 series.  This was a 6 TX and 12 RX unit, which ran 10 watts.  This unit sold for $229 and was just about the smallest of all the offerings at that time.  At Derrick Electronics, I sold jillions of these radios and perhaps many of the folks who read this will have been a customer who bought one (or more) from me and for that I say an enormous, "Thank You!"   The HR-2 and it's brother (HR-2A which followed) had trimmer caps on the TX crystals to ‘net’ them onto frequency but the RX crystals were just ordered for the correct frequency with the hopes that it would be close enough.  The receivers in these early rigs were broad in the IFs and broader in the RF sections.   There wasn't a big need for narrow receivers and close tolerances since there was often only one frequency in use in an area (146.94).  If there was another 2-meter repeater, and you were listening on one frequency and the other repeater keyed up, you knew there was more activity and you could switch to it.  It was like having a scanner before they were available on ham rigs.   I mentioned the broadness of the RF section.......... Tulsa police and fire departments were up around 159 MHz at the time and you could plug in a crystal for their frequency and hear them as you drove along... very handy since there was a lot of aid to the Red Cross by 2 meter local hams and you could hear about an emergency, even before it was on the news.   No, nobody tried to transmit on those public service systems, only receive.

This was a time when many area hams were just getting into the 2-meter side of the hobby and wanted to get on that repeater.  The HR-2 offered a quick, inexpensive, nice-looking way to enter this arena and didn't take up too much space in the vehicle, which allowed it to be "wife-approved."  There was still the spouse discussion entitled; "You're not going to bore a hole in our car for an antenna for that, are you?"  That, too, is for a different and much later article.

One interesting thing, which sold the new transistorized VHF ham radios, happened when the ham reached the time in their life to trade their old car for a new one.  To install one of the old tube type police or taxi radios was a chore.  You had to find a spot, usually in the trunk to place the large and heavy radio case and it had to be securely mounted to that spot.  The cables, often running to different places, had to be mounted out of sight, which often meant tearing up to carpeting or the door channels.  When you did one of these installations, you remembered your experience for a loooooooooooooooong time.  When a new car or truck was purchased, memories of that experience flooded back and MANY of the radios I sold were to a customer who started the conversation with, "I just bought a new car and I'm not about to go though all that installation on my old 80-D;” (one of the popular Motorola rigs), “ into this new vehicle.   I just grabbed my bolt cutters, clipped the wires at each end and tossed it into the trash.  I want one of those new transistor rigs."   I had to admit that it sounded like a good idea to me, too.

All of these radios were crystal controlled with a set of crystals for each frequency being one RX, and if a repeater, a TX crystal on the repeater's input.  If you wanted to operate direct or simplex, an additional TX crystal was needed.   I was fortunate to find a Tulsa-based company that was just getting into the crystal manufacturing production business.  They were actually making crystals for a product that they had developed and sold and while they were not making crystals for their own units, they were glad to keep their equipment and people busy and help fill a niche in the amateur radio market. 

They bought their crystal blanks already cut from a larger crystal rock.  These blanks were within several MHz of the required final frequency and the company had the equipment to lap the crystals to the required frequency.  They had the facilities and the personal to do the job, right up to mounting the finished crystal, stamping the frequencies on the metal shells and soldering the shell to the base with the plug-in prongs.  Just like they say for comedy, timing is everything................... in crystal sales, too, timing was everything.

I not only sold crystals to the local customers, who by this time were coming from surrounding towns, cities, and states, but I had a booming business throughout the country.   Not only were these new 2 meter radios being sold and crystalled up locally but they were being sold all over the US and several foreign countries and, even without the Internet, the word got out that I could provide the correct crystals for these radios, regardless of the required frequencies.  I sold crystals for several years and was fortunate enough to be in the right place at the right time with a good product at a fair price.  A set of crystals (1 RX and 1 TX) in the smaller HC-25 holders was $10 for the pair and we could usually get them in less that a week.  The buyer could purchase just what they needed and/or wanted at the time of purchase and installation and could add to their collection as other frequencies were brought up.  I kept all of the popular frequencies in stock so that crystalling up their new radio was quick and fairly painless and often immediate.  Many old timers who remember V.J.Neimier (SK) - WA5PUX will remember that he gave me the nickname, "Crystal Jim."

I also had a service/workbench in the back of the store, complete with power supply, dummy load, wattmeter, and frequency counter.  When I sold a set of crystals, I would open up the radio, put the crystals into the customer's desired switch positions, and net the TX crystals right onto frequency while they watched.  Remember the RX crystals had no adjustment but the TX crystal positions all had a trimmer, which had to be adjusted to frequency.  It usually only took less than a minute to net a TX crystal 'right on' frequency.  My customers almost always liked to watch the netting procedure and I always invited them to the back room where the equipment was placed so they could stand behind my chair and watch the entire process.

I learned a valuable lesson, when working with my customers, about just how long to spend on each crystal trimmer.  Actually, I learned it quite by accident.  The process was:   after installing the crystals in their sockets I would power up the radio, place the insulated trimmer screwdriver in the first trimmer slot and key the mike.  The wattmeter would indicate the power into the dummy load and the frequency counter would display the frequency.  I would tweak the trimmer until I got it correctly on the desired frequency, then let go of the microphone while I moved the tool to the next trimmer cap.  I discovered, again quite by accident, to not hold the transceiver keyed up too long because, in almost every case, the customer watching me would take a breath when I keyed the transmitter and keep holding it until I let go.  The way I discovered this was, after a couple of times when I was really being super careful and getting the frequency down to a "gnat's eyebrow," when I let go of the mike button I heard a loud and deep "GASP!" from behind me as they resumed their temporarily stopped breathing activity.

I soon learned that if I didn't want someone to turn blue and pass out around the service bench, I'd better make those tuning test transmissions a bit shorter.  Did you wonder, when you started reading, what in the world the title had to do with the story?  Well now you know......................the rest of the story.

written March, 2011 - Published in TARC Newsletter April 2011


This Update Should Be Crystal Clear

By Jim Pickett – K5LAD

 

In the article I wrote for last month’s newsletter I mistakenly identified the crystals used for most of the new 2-meter FM transceivers as being in an HC-6/U holder.   It was only after I saw the article published that it hit me that I’d used the wrong designation for those crystals.  I made the correction in the article when I published it on my website at: http://www.hayseed.net/~jpk5lad/K5LAD%20Memories/Vols%2026-30/MemoriesVol30.htm

I thought, perhaps, that some folks might not be aware of much of the information available about crystals.  Crystals, like hams, can be found is all shapes and sizes.  They can be mounted in many different holder configurations; some large to very large --- some small to very small.  Some are short and round, some are so large that they use banana plugs for their plug-in pins.  Each type of holder has a numerical designation to identify that holder and it’s possible to find drawings of all these holders with dimensions given right down to the fraction of an inch or to a millimeter.  You could search though many different pieces of surplus equipment and never see an example of all of the different types. 

The picture below shows the most common crystals a ham might see.

On the left, the FT-243 is the most common crystal used during WWII.  Every plane that flew, every tank that rolled, every radio set up in a bunker in the battlefield used a radio that required crystals, with few exceptions.   Not just one crystal but usually several or many crystals.  Most of them were the FT-243 type.  Crystals of this size fit into a crystal socket made for it or two of these would fit, side by side, in an octal tube socket made for the larger 8-pin vacuum tubes.  Most of the early CW transmitters used by Novices and new hams in the 50s and 60s used these WWII surplus crystals.  The dream of most Novices back when I started, was to have a whole drawer full of these crystals to cover several different frequencies in the 80, 40, and 15-meter Novice bands.   The more, the merrier was the Novice wish.   Most of the younger set, as was I, had very few and considered themselves lucky indeed if they had at least one crystal per band.

The crystal in the center of the picture, labeled HC-6/U, were the types often used by the police, fire, taxi, etc. radios used by hams on 2 meter FM.  The crystals had smaller pins and could fit into an individual socket made for it or they were often plugged into a crystal oven, a small metal and Bakelite device with a built-in thermostatically controlled heater.  Maintaining the temperature at a near-constant value held the oscillating frequency at a close tolerance was important, and became even more critical as the government required commercial users to adopt narrower frequency deviation requirements.

HC-6/U crystals could be fitted with a slip-on adapter on each pin (sort of like an overshoe) and soldered onto the pin.  The HC-6/U became an HC-17/U with this addition.  The expansion pins on the HC-17/U made the pins the same size as were on the FT-243 crystals.

The HC-25/U was the popular sized crystals used by most hams in the 1970s.  The popular crystal-controlled transceivers used this nice small sized unit.  This is probably the size most familiar to hams who have seen, at least a few years pass since they received their original ham license and perhaps, even newcomers to the hobby.

The HC-18/U crystal beside the HC-25/U is basically the same crystal since it was in the same-sized case.  The obvious difference was the replacement of the solid pins with wire leads.  These crystals were usually wired into the radio, directly onto the circuit board.  Since they were considered nearly permanent, this was the type used in amateur receivers and transmitters in the band-switching heterodyne circuitry.  They helped to determine the range available on a particular switch position.

There were many, many other designations for crystals besides the five types shown here.  Most of them also carry the HC-##/U designation but they’re not the ones often seen or found when cannibalizing surplus equipment so only the most popular type are mentioned here.  I hope this clarifies the type of popular crystals.

Crystals are still used in equipment today, although not to the extent they were used in previous decades.  Most of the frequency determination of today’s radio equipment is made by digital circuitry where the frequency of choice can be easily moved to whatever or wherever the user chooses to set it and can be set with extreme precision.


written April, 2011 - Published in TARC Newsletter May 2, 2011

Back to Memory Menu

On to Volume 31

 

home.gif (1310 bytes) Return to the Home Page