The FT-101 series of transceivers first appeared internationally in 1970 and then domestically inside the United States in January 1971. It gained overnight approval of amateur radio operators for its quality of signal, flexibility and for professional attention to workmanship and design. The modular design of 10 solid state circuit boards on a common chassis with a tube amplifier caught the eye of discriminating hams worldwide.
It was a strong performer. Although far from perfect, the first FT-101's suffered from intermod when strong signals were present during receive and generated spurs on transmit. Hams began to investigate these problems and offer improvements to existing circuit design. The factory responded with a major modification which significantly improved the receiver of the early FT-101's. The serial number revealed which transceiver was "early" and "late". So that the "early" FT-101 hams would not feel obsolete, Yaesu offered the entire modification which made an "early" into a "late" and sold it as a kit along with a 25 page instruction guide. Problems began as many hams lacked the proper test equipment and the know-how needed to make such an upgrade. After months of fighting with customers, Yaesu withdrew the kit (MIR-1 Modification Kit) and would only install it at their factory. Adding to the confusion was the fact that there were five (5) different sub-models within the "early" FT-101 series, the last being the FT-101 "late" model. The situation arose where identical FT-101 radios sat side by side with the only indication of the internal layout was by the serial number.
Additional improvements were made and with the addition of the 160 meter band, the FT-101B was released. Yet more improvements and the addition of a real "RF" speech processor led to the release of the FT-101E model. The "E" model was fully refined with all of the previous problems having been worked out. This was the most popular and the most produced model by Yaesu in the FT-101 series. Three models of the "E" were released. The "E" model with all options, an "EE" (economy) model lacking the speech processor, and the "EX" (extreme economy) model lacking speech processor, 160M crystal, DC options, and microphone. Last in the series was the "F" model which contained all of the modifications, improvements and options throughout the series. Only a few of the "F" models were made which also included an "FE" (economy) and "FX" (extreme economy) model. With fierce competition in the HF market, WARC bands on the horizon, IF shift, AF Notch/Peak, and digital readouts, the FT-101 series moved quickly to the analog "Z" model and then to the digital "ZD" models. The original FT-101 series lasted for 6 years, beginning in early 1971 and lasting through 1977. It was an exciting time for the FT-101 radios and their owners.
There were no "A", "C", or "D" models produced.
The FT-101 first appeared in the January 1971 issue of QST (page 147) sponsored by Spectronics. It would become a familiar full-page advertisement that would be used several times by Spectronics Inc as part of their global ad campaign. It set into motion a new wave of radios and ushered in an exciting time for amateurs worldwide! Each was hand-made by skilled workers with the utmost of pride. Each was unique.
A publication called the Fox-Tango Newsletter captured the "diary" of the FT-101s for all time. Ten publications per year offered thousands of FT-101 owners the opportunity to share problems, solutions, and performance data. The Fox-Tango Newsletters lasted for 14 years. It is the largest collection of user data and factory support information for any radio at any time. It has been preserved and full copies are still available today. Truly a testament to the era and popularity of these radios, even today. Here is a link to the Fox-Tango Newsletter page.
Before we go any further, it is paramount that you understand that high voltages exist within these radios, cables, and accessories. Safety is first and foremost! The FT-101 radios and accessories have voltages which include: 100V, 117V, 240V, +150V, +300V, and +600V. These voltages exit the radio and appear on interface cables. There are no warnings! Within the high power FL2100 amplifier, there is a +2,600 Volt power supply! Within the YO-100 oscilloscope is a +1,300 Volt power supply and a cathode ray tube (CRT). Special tools are required when working on these radios, accessories, and interface cables. Professional repair and service are highly recommended. The following information is presented solely for informational purposes and historical reference.
S/N All Numbers
The tube amplifier consists of a 12BY7A pre-driver stage that feeds a pair of 6JS6C tubes providing a nominal output power of 130 watts PEP SSB, 90 watts CW, 30 watts AM. The 6JS6C tubes are matched to 50 Ohms through a conventional pi-output network. The pi-network transforms the 5500 ohm output impedance of the tubes to a 50 Ohm feed system, provides harmonic attenuation, and can actually match to a variety of output impedances from 25 to 100 Ohms with ease.
The transceivers were made with plug-in boards which could be sent to the factory for replacement or repair. This modular design was unprecedented in the amateur community, which explains why so many FT-101's are still in use today. In fact, board extenders could be purchased to extend any board above the main chassis for measurement, alignment, and repair. For any plug-in board, all voltages, grounds, and signal traces were routed through a single edge connector (facing down into the main chassis). This removed the need for wires and cables to these circuit boards. This yielded a clean and trim internal upper chassis. The bulk of the wiring harness is below the deck of the main chassis where all main circuit board edge connectors are fed. Yes, there are many wires!
FT-101 Top Chassis Photo 106k
FT-101 Bottom Chassis Photo 91k
The most complicated device in this radio is the Band Selector Switch. This is a 12-position rotary switch that runs from the front of the radio to the back. It has 13 sections (wafers A thru M) which route everything from DC voltages, oscillator sections, crystals, tuning circuits, and RF Power in the high-voltage tank and output circuits. One band selector switch position is used for: 160M, 80M, 40M, 20M, 15M, 10A, 10B, 10C, 10D, 11M or AUX, and WWV receive-only. Each position allows the main VFO to cover 500kHz on any band.
The entire transceiver was made of metal. Covers, chassis, shields, shafts, etc., are all metal. Even the plastic RF/S-meter trim and knobs have brass metal inserts. At 35 pounds, there is a lot of metal in this radio! The 10 major circuit boards are mounted with threaded hardware to the main chassis. Very rugged indeed. A clear plastic sheet covers the entire painted surface of the faceplate. A well-cared-for FT-101 will still have this clear plastic front. Years later, vendors offered plastic covers to further protect your FT-101 radio and accessories.
Because critical circuit designs were kept to a manageable size, hams had no problem in offering circuit changes, isolating and repairing problems. This knowledge base was so active that in January 1972, Milton Lowens WA2AOQ, founded the International Fox Tango Club and the Fox Tango Newsletter. The Fox Tango Newsletters were published for 14 years covering the early FT-101's thru the latest Yaesu Transceivers in 1985. By then, surface mount technology and circuit complexity outpaced many ham's ability to maintain this level of equipment. In doing so, new chapters in circuit densities, solid state transmitters, and LSI chips were born, which closed the door (and the covers) to many radios forever.
Frequency Range: 3.5-30 MHz* (80/40/20/15/10 meters) 27.0-27.5 MHz (11/AUX) 10.0-10.5 MHz (WWV receive only) * 160 meters included with B/E/F Series Modes: USB, LSB, CW, AM Power Input: SSB 260 watts PEP DC Input (130 watts output) CW 180 watts PEP DC Input ( 90 watts output) AM 80 watts PEP DC Input ( 40 watts output) TX Freq Response: 300 Hz - 2700 Hz RX Freq Response: 300 Hz - 2400 Hz Standard Yaesu SSB Filter 500 Hz Optional Yaesu CW Filter Optional Filters: 300 Hz - 1800 Hz SSB Narrow(Fox Tango Filter) 250 Hz CW Narrow (Fox Tango Filter) Audio Output: 3 watts AC Power: Rx 35 watts, Tx 300 watts DC Power: Rx 0.5 amps, Tx 20.0 amps Weight: 35 lbs Size: 6"h x 13-1/2"w x 11-1/2"d
FV-101B External VFO
Adding the FV-101B External VFO to your station opens up a new world of operating flexibility. DX'ers will really appreciate this combination. The FV-101B features the same factory sealed, solid state, 1kHz resolution, VFO that is found inside the FT-101 transceiver. This flexibility allows for "split" operation for separate transmit and receive frequencies in any band. Regardless of VFO mode, the exact transmit and receive frequency are available for the Digital Display (YC-601 or DD-1) unit. Please note that any frequency split occurs within the same band. The Remote VFO does not offer cross-band operation. Four VFO modes are supported:
YO-100 / YO-101 Monitor Scope
| YO-100 Schematic A | YO-100 Schematic B |
Adding the YO-100 Monitor Scope allows you to monitor and adjust your transmitter for the cleanest signal possible. Compatible with virtually any transmitter or transceiver, the Station Monitor features a wide range of inputs for all mode monitoring, even RTTY. A built-in 1500 Hz and 1900 Hz tone generators adds to the versatility of this accessory. The two-tone generator generates the proper audio signals to perform "trapezoidal" pattern testing for transmitter linearity. A full complement of front controls allows operator control of all key adjustments. The YO-101 is a solid state version of the YO-100.
YO-100 / YO-101 Monitor Scope Specifications:
The YD-844 is an attractive and functional necessity for serious base-station operation. The unit is made of heavy cast metal which rests solidly at your operating position. The microphone element is dynamic (voice-coil) and is balanced (output levels and impedances) for use with the FT-101 transceiver. Two PPT (push to talk) buttons are available on the YD-844 microphone. One button is a momentary-switch which must be depressed to activate the PTT relay, the second button has a lock feature which allows hands-free operating (while still transmitting via PTT). The microphone element is always connected to the FT-101 so that VOX operations are available without depressing any microphone PTT buttons. The FT-101 transceiver has three transmit options: 1-MOX (Manually Operated transmitter), 2-PPT (Push To Talk), and 3-VOX (Voice Operated Transmitter). These three options are available on the front panel of the FT-101 Transceiver via toggle switch. The YD-844 is available in both high and low impedances. The microphone cord is a 3' coiled, 4 conductor (one shielded) cable terminating into a 4-pin female connector.
The current name and format for world time is called Universal Time Coordinate (UTC). It has also been known over the past years as Greenwich Mean Time (GMT), and the military term ZULU (Z). World time is represented in a 24-hour format based upon the global starting point in Greenwich, England (UK). The UTC time standard does not adjust for Daylight Savings Time.
Accurate time reception can be found by tuning to WWV/WWVH (10.000MHz) or CHU (7.335) on the FT-101 transceiver. Alternate HF/shortwave frequencies for WWV/WWVH are 2.500, 5.000, 10.000, 15.000, and 20.000 MHz. All time formats are AM broadcasts. The WWV (male voice) originates from Ft. Collins, Colorado (USA). The WWVH (female voice) originates from Kauai, Hawaii (USA). The ultra-high accuracy of the WWV 10.000MHz signal is also used to calibrate the FT-101 internal marker located on the Regulator Board (TC1). Radio station CHU in Ottawa, Ontario (Canada) can be found on 3.330, 7.335, and 14.670 MHz.
Setting up your QTR-24 Clock. Using the internet, go to time.is, set your QTR-24 clock to your local time (rear knob adjustment), and rotate the white 24-hour bezel ring (rear knob adjustment) so that the top agrees with the 24-hour value for London/Greenwich Time. See the image of the QTR-24 which depicts a local time of 08:38:45am local, and a GMT time between 13 and 14 hours. Additionally, my time zone is the same as New York. The 24-hour bezel depicts between 8am and 9am (in white) UTC. The QRT-24 is properly set.
Allow the QTR-24 to run for a few days. The speed of the clock may be adjusted via flat blade screwdriver. Clockwise one tick mark to advance the device 5-seconds per day, Counter-Clockwise to retard the clock 5-seconds per day.
The YP-150 is a 50 Ohm dummy load with a built-in RF watt meter. This unit provides a 50 Ohm resistive load to any transmitter operating from 1.8Mhz thru 200MHz. A single PL-259 plug on the rear panel provides the unbalanced input to this unit. The YP-150 is powered by a 117V AC source to run an internal cooling fan to remove heat from the 50 Ohm non-inductive load. Although YP-150 is powered, the front panel meter is not illuminated. A four-position switch allows accurate RF power measurements from 0-6 watts, 0-30 watts, and 0-150 watts. The fourth position is the OFF position which removes power to the fan and disconnects the power measuring unit. The YP-601 can be operated without AC power, but this practice is not recommended, as excessive heat can damage the resistive load. There is no provision for an RF "bypass", therefore this unit is best suited for bench testing and alignment procedures.
The SP-101PB contains all of the excellent audio properties and characteristics as the SP-101 speaker-only model with the addition of a hybrid telephone-patch circuit. This circuit allows the FT-101 transceiver to be interconnected to your telephone circuit to allow telephone calls to be placed with over-the-air stations. The SP-101PB has two level controls to ensure proper audio levels are presented to the telephone lines. A built-in VU-meter is used monitor the phone-input levels. Connection to the telephone line is via (two-wire) twisted pair (normally red and green wires).
NOTE: When using the phone patch, you are engaging in third-party traffic in which you are the control operator. The US does not have 100% third-party traffic agreements with all countries. Example: I was unable to make a phone patch for a ham on a small sailboat on vacation in the Bahamas/C6 to their parents living 3 miles from my house! The US does not have third-party traffic agreements with the Bahamas. Beware!
The YC-601 is a 6-digit frequency display- not a frequency counter. It was not until the later release of the YC-601B that the unit actually performed real frequency counting thru 35 MHz. The YC-601 base unit would simply measure the 500kHz sweep of the internal VFO (8700kHz - 9200kHz) and display the 100kHz, 10kHz, 1kHz, and 100Hz of the tuned VFO frequency. The MHz portion of the display was simply a diode matrix that the user had to select via front panel. This is why you see a band selector on the front. There was also a 4kHz shift between USB and LSB as the FT-101 had this amount of oscillator offset within the unit between modes. The YC-601 had green display tubes. The YC-601B had red display tubes, and the tell-tale front BNC input connector. A popular equivalent for the Yaesu YC-601 was the DD-1 made by Spectronics Inc. Both were functionally equivalent and shared a similar paint scheme and look and feel.
FTV-250 2 Meter Transverter
| FTV-250 Hookup Diagram |
The FTV-250 is a 100% solid state 2M transverter designed to be used with any of the FT-101 HF transceivers to extend its operating capability to include the 2M amateur band. The FTV-250 "transverts" signals to/from the 144-146 MHz or 146-148 MHz frequency segments to the FT-101's 10M band (A, B, C, D positions). This amount of translation is required as the 2M band is 4 MHz wide, and any band on the FT-101 is only 500 kHz (0.5 MHz) wide.
The four (4) 10M band positions on the FT-101 (A,B,C,D) and the two (2) 2M band positions on the FTV-250 yield eight (8) segments of 500 kHz, equaling 4 MHz total spectrum (144 Mhz - 148 MHz). Both units have to be tuned simultaneously for maximum performance. The FTV-250 achieves this broad 4MHz tuning by employing varactor tuning diodes. These diodes change capacitance by varying the voltage across them. This is the purpose of the TUNE knob on the FTV-250. This voltage-tuned RF circuitry was unprecedented in the Amateur market and is an example of Yaesu's commitment to performance and reliability.
The FTV-250 has a self-contained power supply providing all of the internal voltages required for high performance operation. There is a 2-stage RF Power Amplifier which provides approximately 12 watts PEP RF output (20W DC input) in linear service. Users found this power level attractive as many external amplifiers were available (10W in, 160W out), with and without low-noise pre-amps.
Interconnection to the FTV-250 transverter is done thru a series of cables. These cables provide signaling and control between the units. Please note that the voltages which appear on the interface cable include: 12.6V, 100V, +150V, +300V, and +600V! Always ensure that the FTV-250 interface cable is is perfect condition due to the high voltages present. Shielded coax provides low-level 10M RF (28MHz - 30Mhz) signals required for the 2M/10M translation. When the FTV-250 2M transverter is turned ON, it cuts the filament voltage to the FT-101's 100W Power Amplifier so that it cannot be energized. The FTV-250 transverter has the extra connectors on the back to add the FTV-650 6M transverter. The 2M and 6M transverters can be daisy-chained together. Therefore, the FTV-250 can serve as the middle-unit, while the FTV-650 is an end-unit only. Do not lose or misplace the FT-101 ACC Plug!
The 10M-2M frequency translation is as follows: Supposed you want to QSO on the 144.200 USB National Calling frequency in the USA. This frequency is in the bottom 500 kHz segment of the 2M band. The FT-101 is set to 10A and the main VFO is tuned to 28.200 MHz. The FTV-250 is set to 144-146. The resulting 28.200 USB signal is linearly translated to 144.200 MHz. Upon receive, the 144.200 MHz is linearly translated back to 28.200 MHz. Metering on both units allow alignment within 10 seconds. Once aligned, e.g. 144.200 USB, you can easily move ± 50kHz (100kHz total) without re-adjustment. Perfect for calling CQ, rag-chewing, or contesting.
FM and Repeater operation: The FT-101 does not have FM as an operating mode. The modes available are: AM, USB, LSB, and CW. Therefore, it cannot transceive FM signals, so FM operation is moot. Additionally, repeater operation uses a 600 kHz frequency offset, while the FT-101 only has a 500 kHz per band segment. Therefore, repeater operation is not possible even with the Yaesu Remote VFO (FV-101B).
FTV-650 6 Meter Transverter
| FTV-650 Hook-up diagram | FTV-650 Schematic A | FTV-650 Schematic B |
The FTV-650 is a hybrid 6M transverter designed to be used with any of the FT-101 HF transceivers to extend its operating capability to include the 6M amateur band. The FTV-650 "transverts" signals to/from the 50-52 MHz or 52-54 MHz frequency segments to the FT-101's 10M band (A, B, C, D positions). This amount of translation is required as the 6M band is 4 MHz wide, and any band on the FT-101 is only 500 kHz (0.5 MHz) wide.
The four (4) 10M band positions on the FT-101 (A,B,C,D) and the two (2) 6M band positions on the FTV-650 yield eight (8) segments of 500 kHz, equaling 4 MHz total spectrum (50 Mhz - 54 MHz). Both units have to be tuned simultaneously for maximum performance.
The FTV-650 has no internal power supply. All required voltages come from the attached FT-101 host. Please note that the voltages which appear on the interface cable include: 12.6V, 100V, +150V, +300V, and +600V! Always ensure that the FTV-650 interface cable is is perfect condition due to the high voltages present. If the FT-101 is powered on, these voltages are present!
The FTV-650 employs a single tube RF Power Amplifier (6146B/S2001) which provides approximately 25 watts PEP RF output in linear service. Users have found this power level attractive for barefoot operation as well as with an external amplifier.
Interconnection to the FTV-650 transverter is done thru a series of cables. These cables provide voltages and control between the units. Shielded coax provides low-level 10M RF (28MHz - 30Mhz) signals required for the 6M/10M translation. When the FTV-650 6M transverter is turned ON, it cuts the 12.6 filament voltage to the FT-101's 100W Power Amplifier so that it cannot be energized. The FTV-250 2M and FTV-650 6M transverters can be daisy-chained together. The FTV-250 can serve as a middle-unit, while the FTV-650 is an end-unit only. Do not lose or misplace the FT-101 ACC Plug!
The 10M-6M frequency translation is as follows: Supposed you want to QSO on the 50.125 USB National Calling frequency in the USA. This frequency is in the bottom 500 kHz segment of the 6M band. The FT-101 is set to 10A and the main VFO is tuned to 28.125 MHz. The FTV-650 is set to 50-52 MHz. The resulting 28.125 USB signal is linearly translated to 50.125 MHz. Upon receive, the 50.125 MHz is linearly translated back to 28.125 MHz. Metering on both units allow alignment within 10 seconds. Once aligned, e.g. 50.125 USB, you can easily move ±50kHz (100kHz total) without re-adjustment. Perfect for calling CQ, rag-chewing, or contesting.
FM and Repeater operation: The FT-101 does not have FM as an operating mode. The modes available are: AM, USB, LSB, and CW. Therefore, it cannot transceive FM signals, so FM operation is moot. Additionally, 6M repeater operation typically use a 1MHz frequency offset, while the FT-101 only has a 500 kHz per band segment. Therefore, repeater operation is not possible even with the Yaesu Remote VFO (FV-101B).
MMB-1 Mobile Mounting Bracket
| Image | Assembly Instructions |
The MMB-1 Mobile Mounting Bracket was a factory accessory for the FT-101 series radios. It was a sturdy steel tray designed to hold a FT-101 securely for mobile operation. The MMB-1 straddled the transmission "hump" found in cars during the period. The tray has four detents to accept the four feet found on the bottom of the FT-101 transceiver. A strap secured the transceiver to the tray. The only change required to the FT-101 during mobile operation using DC electrical power was the adjustment of the tube bias to 60ma idle current.
Yaesu advertisements in QST hinted at mobile and portable operation, but never a clear photo of how to do it or show one in actual operation. The vehicle in the advertisement appears to be a 1972 Land Rover Series-3. There is no front seat room in this vehicle to mount a FT-101 on the "hump". The practically of mounting a 30+ lbs radio in a vehicle is nil. Therefore, the idea of mobile operation was short lived. Here is an example from 1967 in a 1967 Dodge Dart. Five years later, hump-mount mobile operation was almost impossible to do. Center consoles , heat ducts, and vehicle accessories consumed this space forever. The MMB-1 may be the rarest of all FT-101 parts/accessories in the FT-101 lineup. So few were ever made, the practicality was zero, and 40 years have passed. The assembly instructions above are the only known copy to exist- including the typographical error.
Item Price Price Price Price Price Price Price Price Price Price Model Description Q3/71 Q3/72 Q3/73 Q3/74 Q3/75 Q3/76 Q3/77 Q3/78 Q3/79 Q3/80 ---------|-----------------------------|-----|-----|-----|-----|-----|-----|-----|-----|-----|-----| FRdx400 80M-10M All Tube Receiver $359 $339 FRdx400SD 80M-10M+6M+2M All Tube Receiver $399 FLdx400 80M-10M All Tube Transmitter $299 FRdx401 80M-10M All Tube Receiver FLdx401 80M-10M All Tube Transmitter FTdx401B 80M-10M All Tube Transceiver $599 FTdx560 80M-10M All Tube Transceiver $450 FTdx570 80M-10M All Tube Transceiver $550 FL2000 80M-10M Linear for dx Series $299 $339 FT-101 80M-10M Transceiver $499 $560 FT-101B 160M-10M Transceiver FT-101E 160M-10M Transceiver $649 $729 $799 $695* FT-101EE 160M-10M Transceiver $649 $759 FT-101EX 160M-10M Transceiver $589 $699 FT-101ES 160M-10M Transceiver(50 watt version for Japan market) FT-101F 160M-10M Transceiver $799 FT-101FE 160M-10M Transceiver $759 FT-101FX 160M-10M Transceiver $699 FT-101Z 160M-10M Transceiver $749 $599* FT-101ZD 160M-10M Digital Transceiver $895 $749 FT-101ZD 160M-10M Digital Transceiver (WARC) $799 FT-901D 160M-10M Digital Transceiver (WARC) $1299 FT-901DE 160M-10M Digital Transceiver (WARC) $1149 FT-901DM 160M-10M Digital Transceiver (WARC) $1299 $1459 FL-2100B Linear Amplifier 80M-10M $339 $399 $479 FL-2100F Linear Amplifier 80M-10M $399* FL-2100Z Linear Amplifier 160M-10M $399* FV-101B Remote VFO $99 $109 $135 $116 SP-101 Speaker-Only $19 $22 $25 $22* SP-101PB Speaker with Telephone Patch $59 $59 $67 $57 FTV-650 6 Meter Transverter $149 $199 $235 FTV-250 2 Meter Transverter $199 $275 $225* YC-601 Digital Display (Yaesu) $169 $199 $205 YO-100 Station Monitor Scope (Tube Model) $199 $233 $240 YO-101 Station Monitor Scope (Solid State) $320 $199* FR-101 Analog Receiver 160M-2M $489 FR-101 Digital Receiver 160M-2M $599 $599 $549 FR-101S Analog Receiver 160M-2M $599 $449 $349* FR-101SD Digital Receiver 160M-2M $749 FL-101 160M-10M Transmitter $525 $575 $499 $399* YP-150 Dummy Load - Watt Meter $86 $78 $79* RFP-101 Speech Processor $79 $79 YD-844 Base Station Microphone $29 $29 $29 YD-846 Hand Microphone $16 $16 QTR-24 World Clock $30 $35 $29* FA-9 Fan $19 $15 $20 MMB-1 Mobile Mount for FT Series $19 $19 $23 XF-30C CW Filter 500 Hz $45 $40 $40 XF-30B AM Filter 6kHz $40 DC-1 DC Converter for EX Models $45 $50 Crystals Any FT-101 Crystal 160M-10M $5 $5 $5 DD-1 Digital Display (Spectronics Model) $169 $169 * - Indicates Advertisers offering "close-out" prices to reduce stock.
Full 6JS6C Specification Sheet
There will come a time when the finals in your FT101E will need replacing. The FT-101 transceivers were originally equipped with 6JS6C tubes manufactured by NEC and Toshiba. Other manufacturers tube properties are slightly different from the original 6JS6C tubes. Therefore, a simple modification to the neutralization circuit must be made to the final section of the transceiver. The modification consists of replacing the fixed value 100 pf 1000 VDC mica capacitor with a 10 pf 1000 VDC mica capacitor. This capacitor, C125, is in series with the 10 pf variable neutralizing capacitor off of the plate circuit.
If this modification has not already been completed on your rig, be sure to use a mica or silver mica of at least 1000 VDC. Do not substitute a different type because the heat in the final compartment will change the value, and your tubes will fail prematurely. Also, be very careful to keep all leads short and in exactly the same orientation as the original capacitor.
Before re-neutralizing, open the variable neutralizing capacitor all the way to minimum engagement and follow the neutralizing instructions in the manual. While dipping the PLATE, remember to adjust the neutralizing capacitor for equal value meter reading "dips" (Ic meter position) on both sides of the peak when tuning the PLATE control. WARNING! You are tuning a capacitor in the High Voltage compartment, +600 Volts are present! Always use non-metallic tuning tools. After neutralization, reset the bias to 60ma with CARRIER and MIC settings at minimum.
QST- The following performance data is provided by the American Radio Relay League (ARRL) and their publication QST. A full copy of this table was found on the Technical Information Service section on the ARRL web page. The table depicted over 60 radios and their performance data. I have shown only the Yaesu radios from the 1970's that apply to this web page.
QST Reviews of Amateur HF Transceivers QST | Xmtr | Rcvr Rig Review| Harm. Spurs IMD | Min Sig BlkRng IMD DR 3rdO Icpt Issue | dBpep dBpep dBpep| dBm dB dB dBm ------------------------------------------------------------------------- Yaesu: FT-101B 02/74 FT-101E 09/76 -34 -141 108 81 FT-101Z 12/79 -45 -38 -139 112 78 -22 FT-301 10/77 -55 -68 -40 -133 100 75 FT-901 11/78 -46 -57 -38 -137 114 85
Introduction of the original FT-101, QST Jan 1971:
Page 147. This is the very first time we see the FT-101!
QST Review: FT-101B, Sep 1974: Page 46, Page 47, Page 48. A complete 3-page QST review of the B-model.
QST Review: FT-101E, Feb 1976: Page 38. A 1-page QST update on the E-model.
Misc Station Photos: Nice Station Photo #1, Nice Station Photo #2, Nice Station Photo #3, Nice Station Photo #4, Nice Station Photo #5
Quick Tune-up Procedures
If you have ever purchased a FT-101 transceiver without the Instruction Manual, you know it can be very intimidating to operate until you perform the tune-up process a time or two. Without 'tuning up' your transmitted and received signals really suffer AND could actually damage the tubes in the power amplifier. I always suggest that you download the Instruction Manual for any FT-101 radio or accessory you own. Even older radios have web pages that can provide you copies at very reasonable rates. An Instruction Manual was made for each and every FT-101 radio and accessory. These are free across the Internet. Even the FT-101 Service Manual is available (32MB PDF). See the FT-101 Repair Facilities section on this page for the link. No excuses!
The FT-101 series is a very mechanical radio. The size, selection, and operation of this rig allow for very high-Q circuit tuning. It is a very strong point with the FT-101 series. As with any high-Q circuit, it must be continuously tuned for maximum efficiency. Once learned, it takes only a few seconds to perform. You should re-tune anytime you change bands, change antennas, or move a significant distance (in frequency) from where you last tuned up. This may be as large as 200 kHz on the 10 meter band (10-15 turns of the VFO dial) or as little as 15 kHz on the 160 meter band (one turn of the VFO dial).
Before you begin, you should allow the rig to warm up (with the heaters on) for at least 15 minutes. This allows the rig to become frequency and temperature stable. Put the Meter switch into the 'IC' position with the CARRIER and MIC control fully counter-clockwise. Throw the MOX switch to engage the transmitter and read the meter that is now displaying the idling current. The current should read 60ma on the scale. If it does not, adjust the BIAS control until 60ma is obtained. Move the Meter switch to ALC and ensure a full meter deflection to the right. Adjust the ALC control as needed. Return the MOX switch to normal PTT.
Please remember to tune-up into a well-matched antenna system or dummy load representing a 50 Ohm load. Keep all tune-up steps to under 10 seconds of transmitting to prevent damage to the Power Amplifier tubes! After each 10 second transmission, allow the tubes to cool for 10 seconds. Then repeat. Do not exceed this 50% duty cycle. The tubes can only dissipate 30 watts each! You can put heat into the tubes faster than they can dissipate that heat!
The earlier FT-101 manuals used a tune-up procedure which 'peaked' the output (PO) while 'dipping' the grid (Ic) current. By the FT-101F series, the procedure was simply a 'peaking' (PO) process as depicted in the Instruction Manual. With a little practice, you will be able to perform these procedures within 10 seconds. Really!
Adjust CARRIER, MIC, and PROCESS controls for the proper output as desired. Monitor the Meter for grid current (Ic) and ALC levels (ALC) to ensure that you are not over-driving the transmitter. Both will greatly shorten tube life, cause distorted transmitted audio, and is the prime source of television interference (TVI).
One of the most misunderstood and mistuned modes available on the FT-101 transceivers is the AM (Amplitude Modulation) transmitter. (Second only to the RF Speech Processor!) The FT-101 has one of the best on-air signals for AM that you may ever find in a stock radio. It is also one of the easiest to make a mistake. The most common mistake is measuring AM power the same way that you measure SSB or CW signals using a watt meter. AM is very different.
The most common mistake is running too much carrier power in AM mode. The FT-101 can only deliver 30-40 watts of AM carrier in linear service. The reason for this is that an AM signal contains a steady carrier and two sidebands that contain your audio. The amount of RF power in this modulated AM "envelope" is actually 4-times the carrier. This means that a modulated AM signal with a 30-watt carrier is actually transmitting 120 watts of power. This is the amount of power needed from the power supply to transmit this signal. It is also approaching its absolute power limit. The same is true with the matching FL-2100B amplifier. A 300-watt carrier contains 1200 watts of RF power when fully modulated. There is nothing worse than "cooking" a FT-101 by running AM with a 100 watt carrier. The power supply, tubes, and amplifier components cannot deliver 400 watts of power, are run continuously beyond their maximum rating, and for long periods of time. Beware when purchasing one of these 11 meter 'cooked' radios!
Alignment Points and Procedures
As you know by now, the FT-101 series of radios are very mechanical. From time to time, they will require basic
alignment and calibration. The Yaesu factory knew this and made many of the adjustment points directly accessible
under the top cover. Personally, I let the FT-101 warm-up for 2-hours with the heaters on and covers on so that the
unit becomes temperature and frequency stable. Never try to align or calibrate a cold rig.
Be very cautions of cleaners and solvents on this rig. Tuner Cleaner can be used on mechanical switches. Potentiometer Cleaner on all variable resistors. Use Compressed Air on coils and variable capacitors. Whetting these parts and moving them back and forth may actually dissolve that material which provide the resistive function. Residual oils may actually attract more dirt and dust over time. Solvents should NEVER be used!
There are a few terms you need to know about, how to correctly use, and apply them. Please note that there are many WRONG descriptions on the internet including videos on YouTube. Follow them (with respect to the FT-101) and you are going down the path to mistakes and frustration. Let's get started:
Zero Beat (#1) This is the term used when the absolute value of a single tone is adjusted to zero. This occurs when you hear the high-pitched FT-101's internal MARKER tone and you adjust the VFO so that the tone goes lower and lower in frequency until it is no longer heard thru the speaker. Since the frequency you hear rolls off at 100Hz (you can no longer hear the tone), you go just a fraction more to account for the last 100Hz that you cannot hear. The goal is truly zero-Hz. This is how you adjust the VFO to the MARKER when you: Change Bands or Change Modes (eg: USB to LSB, or from CW to USB, etc.). After you Zero Beat the VFO with the MARKER, you rotate the silver frequency wheel to align with the 25kHz or 100kHz multiple. This puts the FT-101's VFO on-frequency. The MARKER is calibrated with WWV. It is your master frequency standard on all bands.
Zero Beat (#2) This is a term used when you adjust two tones to be equal with each other. It is like tuning a guitar. It is not finding the average between two single tones as you flip some switch back and forth. When you Zero Beat two simultaneous tones being emitted from the FT-101, you will eventually hear the famous "wow wow wow" as the two tones "beat" against each other. As the tones get closer together in frequency, they become indistinguishable to the human ear- and the wow-wow ceases. You have achieved the Zero Beat process. Here is an audio example of the process. At the end of the audio clip (25-28 second mark), the tone is steady. These are the tones you will hear when setting the 10 MHz MARKER used to provide the 100 kHz and 25 kHz Markers. You will Zero Beat the WWV radio signal with the FT-101's MARKER. This will provide an accurate internal frequency reference. The goal is to mimic the highly accurate over-the-air 10MHz radio frequency emission from WWV in Colorado. Adjust the MARKER trimmer capacitor with a non-metallic tuning tool. This trimmer capacitor is labeled "MARKER TC1" on the FT-101 Top Chassis Photo.
WWV The radio station WWV plays a vital role with the FT-101 series radios. WWV transmits a highly accurate frequency carrier at exactly 10 Mhz. This signal is received by the FT-101 radio tuned to the WWV Band segment and is ultimately used to zero-beat with the internal MARKER frequency to derive accurate frequency calibration. Since WWV transmits like any other radio station, it will not be heard all the time. It may take several attempts to get a strong S7 on the FT-101's meter to perform accurate MARKER calibration. Be patient. This is typical of radio signals in the 30 Meter band, your distance from Ft Collins Colorado, time of day, solar activity, and the effectiveness of your antenna.
Sizes and Weights: The sizes and weights for each piece of Yaesu equipment is listed above. None of the Yaesu transceivers or accessories exceed the size and weight limits imposed by any of the major common carriers such as: UPS/FedEX/USPS. Shipping should be a very straightforward process, and with a little planning, your package should arrive in the same condition as it was shipped.
Estimating Final Weight: Accept the fact that shipping will add 20%-25% to the actual weight of any unit. Yes, a 30 pound FT-101E transceiver with manual and power cords will actually weigh 38 pounds ready to ship. A two pound YD-844 microphone will weigh 3-4 pounds if packed properly. The heaviest in the series, the FL-2100 amplifier (41 lb.) will tip the scales at 52 pounds at the counter! Don't underestimate the weight of shipping!
Packing Considerations: Remember that you are responsible for ensuring that the equipment is packed properly and safely for its journey. The longer the trip the better it must be packed, especially overseas. NEVER use newspaper for any of packing material. It is not resilient to compression, it holds moisture, and will leave ink on painted and plastic surfaces. When possible, use the original Yaesu packing box and materials. Prior to shipping any unit, remove all AC cords, microphones, accessory plugs, and the brass spinner on the main VFO dial. Do not use tape on any plastic or painted surface. Ensure that all covers are on tight. Put the unit in a plastic bag (as a moisture and dust barrier), and then wrap in bubble wrap. Select a box which allows at least 2" on each side to survive a hard "knock" while in transit. Place enough fill to cover 2" in the bottom of the box. Insert the unit and fill completely with packing to the top.
FT-101 Repair Facilities
Since FT-101 parts are very hard to find, please ask ANY repair facility how they obtain parts. If they simply call the Yaesu factory, you may be sending your FT-101 to the wrong place or waiting a very long time. I prefer to deal with repair facilities that specializes in FT-101 parts, which means in some cases, they must use 'parts rigs' to find that hard to get part. Basic capacitors, resistors, and transistors are not a problem. But, there are times where a substitute is not available. You will be glad that your rig is being repaired by a "FT-101 ready" facility.
More info to follow.....
| FT-101 AC Power Transformer Connection Diagram
| AC and DC Power Connection and Pin-out Diagram |
Credits and Source References
This web page was created back in late 1997 and posted in January 1998. Back then, web access was thru
a 14.4k or 28.8k dial-up modem. The goal was to create a web page that was bandwidth friendly and basic in
layout- even for a 14.4k modem. At that time, there were web pages that would scan your web page and
offer reduced image resolution and a reduced color pallet (Website Garage). It was a very
effective way to reduce bandwidth demands and still get your message out. As a point of reference,
the image below is larger in size than all of the text and formatting of this page combined!
Special thanks to the MIT Radio Club W1MX for the use of their extensive technical library. They had every radio publication ever produced for the past 60+ years. Looking back 40+ years is never easy!
73, for now.
Or send email to: NW2M at QSL dot NET
Last Update: 11/03/2013 AOR