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From a 2014 Balanced Modulator newsletter article

HEATHKIT FADES AWAY

By Billy Williams, N4UF 

In 1992, a New York Times article titled Plug Is Pulled on Heathkits, Ending a Do-It-Yourself Era stated "before there were nerds, before there was a Silicon Valley, there were Heathkits, which let tens of thousands of ambitious amateurs and aspiring engineers build their own radios, televisions and other electronic equipment."

The article added "the Heath Company is closing out the last of its kits to concentrate on faster-selling home-improvement products and educational materials. Heath's kit sales have steadily declined since 1981, victims of reduced leisure time, declining prices that make it cheaper to buy fancy radios and electronic equipment than to build them, and the seduction of technically oriented consumers by personal computers......it is also the passing of an American institution that fostered learning-by-doing in its finest form. As one-hour film processing displaces the home darkroom, and inscrutable fuel-injection systems stymie the sidewalk auto mechanic, so goes do-it-yourself electronics."

Heathkit sputtered along for another 20 years after that article but in terms of producing new ham gear, Heathkit was dead.

Hams still use Heath equipment today--linear amplifiers, SB series transceivers, SWR bridges, dummy loads and other test gear.

EARLY HEATH

The Heath Company began as an aircraft company in 1912 when Edward Bayard Heath purchased Bates Aeroplane Co. In 1935, Howard Anthony purchased the then-bankrupt Heath Company and sold accessories for small aircraft. After World War II, Anthony entered electronics and bought a large stock of surplus wartime parts with the intention of building kits with them.

One lot of parts purchased by Anthony included hundreds of 5BP1 cathode ray tubes. In 1947, Heathkit introduced its first electronic kit, the O-1 Oscilloscope, that sold for $40. The O-1 used those 5BP1 tubes as screen waveform displays. It was a big seller.

The Heathkit sales premise was that by investing the time to assemble a Heathkit, a purchaser could build something comparable to a factory-built product at a significantly lower cost.  

Commercial factory-built electronic products were constructed from generic, discrete components such as vacuum tubes, tube sockets, capacitors, inductors and resistors.  These were essentially hand-wired and assembled. A Heathkit builder could perform the same assembly tasks himself.

The second kit created was the VT-1 Vacuum Tube Volt Meter (VTVM). The third kit was a G-1 Radio Frequency (RF) Signal Generator.

By mid 1948, kits included a G-2 Sine and Square Wave Audio Generator, a T-1 Signal Tracer and a C-1 Condenser Checker.

The Heathkit AT-1 Transmitter was a basic Master Oscillator Power Amplifier (MOPA) unit.  Priced at $30, the AT-1 used a crystal-controlled 6AG7 oscillator, a 5U4 rectifier plus a 6L6 final output tube. Input power was 25 to 35 watts.  The AT-1 represented a solid rig for a novice in 1951 that was relatively easy to construct and operate.

After upgrading, an operator could attach a Heath VF-1 Variable Frequency Oscillator ($20) to cover 160-80-40-20-15-11-10 meters.  It used an 0A2 voltage regulator tube to provide a stable voltage for the oscillator. Ceramic coil forms, solid construction and high quality components were used to help increase stability.

A coupler such as the Heathkit AC-1 ($15) was recommended to correctly match an antenna to the AT-1.  A companion to the AT-1 was the Heath AR-1 Receiver ($24) which included six tubes and three bands. This was followed by the AR-2 Receiver ($26) that covered four bands.  Both were general coverage receivers with ham and shortwave broadcast frequencies.

The AR-2 included a beat frequency oscillator for CW reception which the AR-1 lacked. Additional selectivity and sharper receiver tuning came with addition of a $10 QF-1 Q Multiplier.

1950s

By 1952, Heath added a line of kits for the high fidelity audiophile.  Starting with its A-7 Economy 6-Watt Amplifier kit ($15), Heath products included the A-8 High Fidelity 20-Watt Amplifier ($34) and WA-A1 Amplifier ($70) which included a pre-amplifier.  FM radio broadcasting was primitive and obscure in those days but Heath had its FM-2 Tuner priced at $22.50.  For AM listeners, Heath sold a BR-1 Five-Tube Broadcast Band Receiver for $20.

Heath's product line in 1952 included a large selection of test equipment.  For measuring capacitance and inductance, there was the QM-1 Q Meter ($40). The DR-1 Decade Resistance  ($20) and DC-1 Decade Condenser  ($17) were aimed toward electronic experimenters and those doing design work. With these devices, resistance from 1 ohm to 99,999 ohms and capacitance from 100 pF to .111 uF could be selected. The O-8 Oscilloscope with improved 1 mHz response($40) was new in 1952 along with a VC-1 Voltage Calibrator ($10) for more accurate oscilloscope readings.  The S-2 Electronic Switch ($20) allowed two waveforms to be viewed simultaneously--a big breakthrough in days before dual-trace scopes.

The V-6 Voltmeter kit ($25) was a general purpose test bench multimeter. Using the Heath 336 High Voltage Probe ($6), up to 30,000 volts could be measured. For precision AC voltage measurements, there was the AV-2 AC VTVM  ($30).  The M-1 Handitester  ($14) was a portable multimeter.

For measuring tuned circuits and antenna resonant frequencies, there was the Heath GD-1 Grid Dip Meter ($20) which was a very crude forerunner to modern antenna analyzers. Measuring antenna performance was not easy in the 1950s.  Measurements took patience and had to be done near the antenna feedpoint to be accurate. The GD-1 was designed for "convenient one-hand operation" according to advertisements that appeared in Radio & Television News and other electronic publications.

The Heath IB-1B Impedance Bridge for industrial laboratories and well-to-do hams sold for $70. A less precise AM-1 Antenna Impedance Meter ($15) was introduced in 1956 aimed toward hams. It used a bridge circuit to measure antenna impedance and SWR.

For repair shops, Heath had its TS-2 TV Alignment Generator  ($40), PS-2 Regulated Power Supply ($30) which produced 160-400 volts DC, SG-7 RF Signal Generator ($20) and TC-1 Tube Checker ($30).  To power 6-volt car radios on the test bench, the BE-3 Battery Eliminator ($25) produced 0 to 8 volts at up to 15 amps.

For testing car radio vibrators (mechanical failure-prone DC to AC converters used in car radio power supplies) the VT-1 Vibrator Tester kit was $15. The AG-8 Audio Generator ($30) included an extended range up to 1 MHz and the T-3 Signal Tracer ($23) featured a noise locator and an electrom beam indicator "magic eye" tube for precise signal strength observation.

Howard Anthony died in 1954. Heath was acquired by Daystrom, a management holding company. Daystrom was absorbed by oilfield service company Schlumberger Limited in 1962.  The Daystrom/Schlumberger period was Heathkit's most successful.

The DX-100, a full-feature transmitter, appeared in 1956.  It transmitted CW and AM voice with 100+ watts output on all HF bands. It included a built-in power supply and VFO, weighed 100 pounds and cost $190. The following year Heath introduced two crystal-controlled, scaled-down transmitters: the CW-only DX-20 model, meant for beginners--and the DX-35 which was capable of both CW and AM phone operation. Both models covered six bands, only lacking the DX-100’s coverage of the 160m band. At $35 and $55 respectively, these were very affordable. The DX-35 was superseded by the improved DX-40.

By 1957, Heath beefed up its audiophile offerings with the AA-81 Amplifier. It produced 35 watts of monaural power.  For serious audio enthusiasts, Heath offered an AA-1 Audio Analyzer kit ($50) that combined an AC VTVM, audio wattmeter and an intermodulation analyzer in one unit.  

Heath went stereo in 1961 with the AA-100 Stereo Amplifier rated at 25 watts per channel.  It was a unit of reliable quality produced several years before other major hi-fi companies produced anything comparable.

1957 Heath breakthroughs included its XR-1 Transistor Portable Radio ($35) that included "six Texas Instrument transistors selected for extra good sensitivity and selectivity." It included a 4-inch by 6-inch permanent magnet speaker and was powered by six "D" flashlight cells.  

For boaters and navigators, the DF-1 Transistor Radio Direction Finder ($50) was a portable six-transistor receiver with a directional loop antenna.   The FD-1 Fuel Vapor Detector ($36) claimed protection for "your boat and its passengers against fire or explosion from undetected fuel vapor."  To help keep a boater's batteries charged, the CI-1 Marine Battery Charge Indicator ($17) provided better reliability than a hydrometer.  No more danger from working near acid in small enclosures. And the ED-1 Electrolysis Detector ($10) monitored "currents between a boat's common ground and underwater fittings, except on boats having metal hulls."

For uranium hunters and civil defense enthusiasts, Heath introduced the RC-1 Professional Radiation Counter ($80) which could measure up to 60,000 counts per minute and up to 10 milliroentgens per hour.  It used a 900-volt bismuth tube and a beta/gamma sensitive probe.

The PM-1 RF Power Meter ($15) measured the relative field strength produced by a transmitter.  While output power wattage could not be determined, changes in transmitter signal strength were noticeable when the meter's indication decreased. It was also useful for determining front-to-back ratios of beam antennas.

The AM-2 Reflected Power and SWR Bridge ($16) was the first of a line of Heathkit SWR bridges and power meters.   Prior to this type of bridge, SWR measuring devices could only be used at low power and could not be left in-line during normal operation. SWR meters eventually became a fixture in many ham stations and many were Heathkit models.

Introduced in 1957, the AM-2 remained in production until 1962 when it was replaced by the HM-11. The differences between the AM-2 and HM-11 were only cosmetic, switching from a silver and dark gray paint scheme of the DX-20/35/40 series to the gray and green motif of the DX-60/TX-1 families. The circuit was unchanged. The HM-11 was produced until the end of 1965 when it was replaced by the HM-15.

Unlike some other kits, Heath provided excellent step-by-step instructions in comprehensive manuals.  After assembling hundreds of parts onto circuit boards and between points on a metal chassis, kit builders measured circuit resistances to minimize chances of a big smoke blowout when power was applied for the first time.

A deluxe line of Heath amateur equipment was introduced in 1959. The TX-1 Apache Transmitter and the RX-1 Mohawk Receiver were about the same size and weight as the DX-100 but had updated styling and a new cabinet. The RX-1 was Heathkit’s first full-featured amateur band receiver. Both units used a slide rule dial with a scale that changed from one band to another on a rotating drum to provide more accurate tuning. Together, Heath’s top-of-the-line pair sold for $500.

The SB-10 SSB Adapter ($90), introduced in 1959, allowed both the Apache and DX-100 to operate using SSB voice. The next year, a matching kilowatt linear amplifier, the KL-1 Chippewa ($400), was added to the line. The HX-10 Marauder Transmitter ($335) was a redesigned replacement for the Apache, operating on SSB without needing an external adapter. It appeared in the 1962-63 catalog along with a new linear amplifier, the HA-10 Warrior ($230). These behemoths also weighed nearly 100 pounds.

Most hams, even mobile operators, used separate transmitters and receivers. For those who didn't want to throw multiple switches to go from receive to transmit, the VX-1 Electronic Voice Control kit sold for $24. It included a primitive VOX arrangement--a switchover could be accomplished by merely speaking into a microphone.  Completing the line, the VHF-1 Seneca Transmitter ($160) covered 6-meters and 2-meters.

During the cold war, an enemy attack could come at any time.  In each area, a local AM broadcast station was assigned to relay alerts of impending attack by switching its carrier signal off and on in a sequence that triggered alarms. While transmitting, hams were required to monitor for Conelrad alerts.  FCC didn't want enemy planes to use radio signals to home in on targets hence the need for all stations to cease transmissions if an attack was underway. Heath's CA-1 Automatic Conelrad Alarm was designed to give instant warning when the designated AM station cut its carrier signal.

The CA-1 automatically turned off a ham's transmitter when an alert was detected.  It also activated a red indicator to advise the operator that we might be under attack--or that the system was being tested.  The kit included a heavy duty relay, a thyratron tube, a built-in power supply and a neon lamp which indicated that the CA-1 was on duty monitoring the AM Conelrad station. All this for only $14.

As popularity of mobile operation grew, Heath added the MT-1 Cheyenne Mobile Transmitter  ($100) and the MR-1 Comanche Mobile Receiver ($120).  Each weighed around 15 lbs.  A MP-1 Mobile Power Supply  which used a pair of 2N442 switching transistors to power both the MR-1 and MT-1 sold for $45.  It weighed only 8 lbs. and was a great improvement over bulky and balky mechanical vibrator units that operators used before transistors became widely available. The AK-7 Mobile Speaker sold for $6 and the AK-6 Mounting Bracket cost $5.  The PM-2 Mobile Power Meter was $13.

1960s

 The Heathkit DX-60 CW and AM Transmitter was added in 1962 to replace the DX-40. Price was around $80.  Designed for the 80 to 10 meter ham bands, the DX-60 used a 6146 final RF tube to produce 90 watts peak power on AM and CW.  A plate current of 120 ma corresponded to the 75 watt maximum input allowed a Novice ham in the 1960's. A front panel switch selected several crystal positions or an external VFO.  Heath offered the HG-10 as a matching VFO and the HR-10 as a matching receiver.

The "Tener" "Twoer" and "Sixer" were a family of lunchbox-sized transmitter-receivers. The HW-19 ($40) covered ten meters using a tunable superregenerative receiver and a 5-watt crystal-controlled transmitter. The HW-29/29A 6-meter lunch box ($45) produced 2 watts output and the HW30 2-meter unit ($45) was a similar 5W model.  Building a lunchbox took 6 or 8 hours.  

An 11-meter CB version, the CB-1, was also available. Kits included a ceramic element microphone and two power cords--one for use with the built-in AC power supply and another for use with a DC power supply, such as the Heathkit GP-11, for 6 or 12 volt mobile operation. The two-toned color scheme was mocha and beige.

For short wave listeners, Heath offered its GC-1A Mohican Portable Receiver ($110) in 1961. Powered by eight flashlight batteries or by an optional internal XP-2 ac power supply module ($10), the Mohican was one of the first transistorized general coverage receivers. It tuned from 550 kHz to 32 MHz in five bands. The circuitry included 10 germanium PNP transistors and 6 diodes. The  Mohican cabinet reflected Heath's "chrome-knob, green cabinet, and tribal name" era which was primarily from 1959 to 1963.

For those on a tight budget, the GR-81 Economy SW Receiver sold for $24. It was a three-tube, four-band regenerative set covering 140kHz to 18 mHz. Tubes included a 35W4 rectifier, 50C5 audio output and a 12AV7 dual triode as the regenerative RF detector and a first stage of audio. In 1965 came the GR-64 SW Receiver ($40) with four tubes plus solid-state rectifiers. It included BFO, Bandspread, and an S-meter.

The mid-1960s brought transceivers to the Amateur Radio mainstream. Until then, most HF operators used separate receivers and transmitters to communicate.  Advertisements in ham magazines for early transceivers appeared in the late 1950s concurrent with the rise in popularity of single sideband as a voice alternative to amplitude modulation.  

The first widely distributed HF transceiver was the Collins KWM-1. At $820 plus $100 for an AC power supply, it was not cheap. The first units were sold in 1957. The KWM-1 was a true transceiver in that the frequency-determining circuitry was common to both the transmitter and receiver. Most of the amplifiers and other stages were used in both the receive and transmit phases.   Heath introduced its HF transceivers with three single-band SSB-only units, followed by one of its most successful lines, the SB-100 series.

Heathkit introduced its HF transceiver line in 1964. Priced at $120, each unit covered only SSB on one band. Transceivers came in three models: the HW-12 for 75 meters, the HW-22 for 40 meters and the HW-32 for 20 meters.

In 1965 Heath offered its first HF all-band transceiver, the SB-100, for $360. The SB-100 and subsequent models SB-101 and SB-102, were among Heathkit’s best selling products.

In 1969, a lower-priced version, the HW-100, ($250) followed by the HW-101, became popular. An external AC power supply such as the Heath HP-23A ($50) was required for Heath transceivers.  Mobile operation required an HP-13 DC power unit ($65). For $100, an SB-640 External VFO allowed split-frequency operation for Heath transceivers.

The SB series was Heath's top-of-the-line Amateur Radio equipment. Performance was somewhat competitive with stalwarts like Collins and Drake.  As with Collins S-Line, these Heath products were designed to operate together in various combinations as a system. When used together, the SB-300 Receiver ($260) and SB-400 Transmitter ($325) could transceive and had other features of the S-Line, including crystal bandwidth filters and 1 kHz tuning dial resolution. By designing them as kits and using less expensive construction, Heathkit offered these units at much lower prices compared to Drake and Collins. A matching SB-200 Linear Amplifier, priced at $220, completed the line in 1965.

One handy SB accessory was the SB-620 Scanalyzer ($120). It replaced the earlier HO-13 Ham-Scan Panoramic Adaptor with a more versatile and useful unit. The SB-620 was a spectrum monitor or panadaptor and served as a bandscanner with a CRT display.  Input was fed from the IF strip of a receiver or transceiver to display the presence of signals within an adjustable band of frequencies along with spectrum analysis with sufficient resolution to observe distortion products, carrier/unwanted sideband suppression and spurious signals from RF equipment.  

The SB-610 Signal Monitoring Scope ($80)and SB-600 Communications Speaker ($20) were other popular accessories  The SB-630 Station Console ($80) included a 24-hour clock, SWR meter and ten-minute ID timer.  These accessories were styled to match SB receivers, transmitters and transceivers.

The SB-220 Two KW Linear Amplifier was a big brother to the SB-200. Introduced in 1970, it used a pair of 3-500Z power amplifier tubes and sold for $370.  Many SB-220s remain in use today. The final model in the original SB-series was the SB-303 Receiver ($345), a solid state replacement for the SB-301.

1970s

A breakthrough for CW operators was the HD-10 Electronic Keyer ($40) with all solid-state circuitry "for perfect characters...no sticking relays or contact bounce." The familiar HN-31 Cantenna Transmitter Dummy Load cost $10.95--not including the oil for the paint can shaped dummy load. Heath produced its first 2-meter FM transceiver, the HW-202, in 1973.  It had 10 watts output, was crystal-controlled and sold for $180. The DC power supply was an extra $30. With an HA-202 2-Meter Amplifier, power was boosted to 50 watts.  For HT users, Heath offered an HA-201 RF Amplifier that boosted 1.5 watts up to ten. An HM-2102 VHF SWR Bridge/ Power Meter sold for $30.

Heath added two CW-only transceivers in 1972: The HW-7 QRP ($70) and HW-16 Novice rig ($100).  Both covered 80, 40 and 15 meters--the only bands available to novices at that time. Other new kits included the GC-1005 6-Digit Electronic Clock ($55); IC-2008 8-Digit Calculator ($130!); Crystal-controlled GR-110 VHF Scanning Receiver ($120); IM-1202 Digital Multimeter ($80); IB-1100 30 MHz Frequency Counter ($170); IB-1101 100 MHz Frequency Counter ($270) and IO-103 5-inch Triggered Sweep Oscilloscope ($230).  For SB-102 owners, the SB-650 Digital Frequency Display was available for $180.

Foreign manufacturers competed fiercely.  Kenwood's TS-520 and the Yaesu FT series came assembled at prices equal to or cheaper than Heathkits.  Unlike Heathkit transceivers, other units included built-in AC power supplies and could be powered directly from 12 volts DC for mobile use. The days of hams saving considerable money by building Heathkits were ending.  In 1975, Heath upgraded its SB series to produce its last major group of HF ham gear.

An advertising campaign heralded the SB-104 Transceiver as "the most advanced design in Amateur Radio...completely solid state with over 275 devices including 31 ICs, 75 transistors and 171 diodes.  The result is a design that runs cooler, quieter, better, longer.  The four finals are totally protected." 

The SB-104 was broadbanded with no tuning needed and included a 6-digit readout.  It sold for $670 with options including a $25 noise blanker and a $35 400 Hz CW filter. A revamped accessory line included the HP-1144 AC Power Supply ($90); SB-634 Station Console (RF Wattmeter, SWR Bridge, Phone Patch) for $180; SB-644 Remote VFO ($120); SB-614 Station Monitor with CRT display ($140) and SB-604 Speaker ($30). A new solid-state HD-1410 Electronic Keyer ($50) was smaller than the older HD-10. 

Heathkit expanded its offerings to include color sets, more television service equipment and even a GD-1380 Video Game unit which incorporated the popular AY-3-8500 pong chip, used widely by many manufacturers. The unit offered three variations of two-player Pong, a single player practice mode and two shooting games. All in black and white.

Heathkit's color television, the GR-2000, had a VHF/UHF varactor tuner instead of the rotary contact mechanical design used in older sets.  The solid-state chassis included 19 ICs.  The GR-2000 came equipped with a built-in dot generator for alignment.  The chassis and CRT cost $670.  A remote control was $90 and cabinets started at $155.  Heath's catalogue contained nearly 400 different kits in the mid 1970s including diverse items like an OL-1155 Aircraft Strobe ($55) and CI-1080 Exhaust Analyzer ($60) to check an auto's tune-up.

In 1977, Heath introduced the 5280 line of five solid-state low-cost test equipment pieces that were powered by batteries or a common power supply.  It included the IG-5280 RF Oscillator, IB-5281 RCL Bridge, IG-5282 Audio Oscillator, IT-5283 Signal Tracer ($43) and IM-5284 Multimeter. When Heathkit went out of the kit business only two of these kits were still being made, the audio oscillator and the signal tracer.

As smaller ICs and surface-mount components, a challenge for kit builders, became more prevalent--it became harder to produce kits that people could build at home using basic hand tools and soldering gear.  Wired products became cheaper because of advancements in engineering and manufacturing. One could buy a quality assembled unit for less than what a kit cost, without needing to spend many hours building it. Instant gratification became important in the 1980s; fewer people built kits.

HEATH ENTERS THE COMPUTER AGE

"Heath was an early player in the personal computer business, and it was the computer unit, Heath Data Systems, that prompted Zenith Electronics to acquire the company in 1979 for $63 million. From that core grew Zenith Data Systems with annual revenues of more than $1 billion," according to the New York Times. "The kinds of people who used to build stereo amplifier kits learned how to program and now spend their leisure time writing software."

The H8, released in late 1977, was the first computer available from Heathkit. Although the H8 was relatively inexpensive at $379, the stock H8 included only a chassis and a CPU card with an Intel 8080 microprocessor. At least one H8-1 Memory Board with 4K of RAM at a cost of $140 was required to run any substantive software programs. To use an audio cassette drive for data storage, a $110 H8-5 Serial I/O Card was needed. And to upgrade to the floppy drive system, you needed at least 16K of RAM.

For reliability, the CPU board came pre-assembled, but everything else was in kit form. In 1978 the H-17 Dual-Floppy Drive became available for $675. Previously only an audio cassette recorder could be used for data storage.

The H8 hardware was not compatible with any other computer system.While some systems used the the common S-100 bus scheme, Heathkit designed their own 50-pin expansion bus, with ten expansion slots available in the H8.

Heath shifted to producing educational products including digital trainers, AC/DC electronic experimenters and microprocessor trainers with which students programmed a Motorola 6800 uP chip using machine language in order to understand how computers functioned.

Many colleges and electronics schools used Heath trainers during the 1980s and  1990s.  Also robots called HERO (Heathkit Educational RObot). Models included the HERO 1, HERO Junior and HERO 2000. HERO 1, introduced in 1982, was a self-contained mobile robot controlled by an onboard computer with a Motorola 6808 CPU and 4 kB of RAM. The robot featured light, sound, and motion detectors as well as a sonar ranging sensor. An optional arm mechanism was available. The robot spoke several phrases and was also capable of remembering and repeating back its masters name, singing songs, reciting poems, and making its own sound combinations to speak robotic gibberish.  

A smaller version, called HERO Junior, was released later. Heathkit intended it for the home market, and made it less complex and more self contained. HERO Junior also used a 6808 processor.

At one time, there were many Heathkit stores including one in Jacksonville. Schlumberger, Heath's parent company since 1962, sold it to Zenith Radio Company in 1979 which made Heath part of Zenith Data Systems (ZDS).  In the mid-1980s, one of Heath's final Amateur Radio offerings was the SB-1000, a 1 kw pep linear amplifier. Produced under an agreement with Ameritron, the SB-1000 used a single 3-500Z and sold for $740.

In 1989, Zenith sold ZDS to Groupe Bull with Heathkit included in the sale. In 1995, Bull sold Heathkit to HIG, a private investor group, which then sold it to another investment group in 1998.

The Heath/Zenith name and products were next sold to DESA International, a maker of specialty tools and heaters, with Heath mostly dormant until August 2011, when a return to the kit building business was announced.  In September, Heath said that it would again sell Amateur Radio kits.

A Michigan newspaper recently reported that Heathkit Education Company has declared bankruptcy and closed after defaulting on its lease. According to the paper, Heathkit employed more than 1800 people at its peak after World War II.

Unfortunately, plans did not work out and Heathkit apparently is now gone for good.

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