Title: Yamaha SY77
Content:  Yamaha SY77 is a 16 voice multitimbral music workstation first produced by Yamaha Corporation in 1989. The SY77 is a synthesizer whose architecture combines AFM (Advanced Frequency Modulation) synthesis, AWM2 (Advanced Wave Memory 2) for ROM-borne sample-based synthesis, and the combination of these two methods christened Realtime Convolution and Modulation Synthesis (RCM). The same technology was also packaged in a rack-mounted module released simultaneously, the TG77. The SY77 is equipped with a 61-key keyboard with velocity and aftertouch; has a pitch wheel and two modulation wheels (the latter being quite a rare feature among keyboards in general); and has a large backlit LCD display, expansion slots, floppy-drive, on-board effects, and a 16,000 note sequencer. Programming is performed through a keypad on the front panel. When the SY77 was released in late 1989, its initial prices were close to $3000 USD/£2000 GBP. In 1991, it was followed by the SY99, a successor that cost ~$4000/£3000 and expanded its capabilities with a 76-key keyboard, the ability to load user-specified samples for AWM, a more advanced effects unit, and other features.
Title: Yamaha SY77
Content:  place of elementary signals like the sine wave. These technologies, both alone and in combination (the latter giving rise to the name Realtime Convolution and Modulation), can generate rich, layered, multi-timbral sounds, and there are large libraries of patches available for the SY77. Sound sets on floppy disks are available online with patches and presets ranging from emulations of classic synthesizers and ambient pads, to percussion and organ sounds. A single 720 kB (DD) formatted floppy disk can hold over 400 patches. The TG77 lacks the disk drive but can still load patches and settings via MIDI SysEx. However, software applications exist that can convert previously disk-only and thus SY77-only files into a TG77-compatible format.
Title: Yamaha SY77
Content:  SY77 is a hybrid between two technologies, AWM2 samples and AFM (Advanced FM). The Montage has an AWM2 engine, the same found in the Motif series, With the ability to import custom samples to the internal flashrom like the SY99. The newly designed FM-X synthesis engine is capable of delivering 8 operators in 88 algorithms, each with multiple harmonic waves along the standard sine wave found in FM. It also has the same resonant filters found in contemporary Motif synths, as well as a complex modulation interface that includes an envelope follower, motion sequencer and more. New to the Montage is the ability to process external audio and use it as a modulation source in its FM-X engine.
Title: Yamaha TG77
Content:   Yamaha TG77 is the rack-mounted equivalent of Yamaha Corporation's SY77 synthesizer workstation. It, too, is a 16-voice multitimbral music (synthesizer) utilizing Yamaha's Advanced Frequency Modulation; Advanced Wave Memory; and the combination of these two systems, either by layering together or by modulating an AFM voice by an AWM wave, a synergy termed Realtime Convolution and Modulation Synthesis (RCM). The unit came into production in 1989, simultaneously with the SY77. The 77 series (and its successor, the SY99) feature various filters, which digitally model those of analog equipment and include the popular feature of self-oscillation from the latter. Each of up to four Elements within a Voice can have its own filter, which can be controlled by a dedicated envelope generator. The 
Title: Siel DK70
Content:  a DEG (for Digital Envelope Generator). Digital components were much cheaper at the time and this allowed the DK70 to approximate the sound of an analog synth, but have 8 note polyphony without being cost prohibitive to the average user. An unusual feature of the DK70 is that, while it appears to have the form factor of a standard synth, it has guitar strap pegs and can be used as a keytar. (The Poly-800 also had this feature.) An accessory called the "Stage Set" can be attached to the left side to provide a grip (similar to that of the SH-101), where the player may manipulate a ribbon-style pitch bender, as well as have access to buttons that 
Title: Sony SMC-70
Content:  The SMC-70G contains additional hardware to support video production, contains a higher wattage power supply (1.3A at 120V - 156 watts), an additional externally available expansion port (a total of four) on the expansion bus, two additional internal I/O expansion ports (used by the genlocking hardware), and an NTSC video genlocker. The SMC-70GP has a PAL video genlocker. The system interfaced with video devices (e.g. laserdisc player, videotape system) to mix computer generated graphics with live video.
Title: Yaesu FT-7(B)
Content: VF-7 separate VFO (and only for FT-7); ; YC-7B digital readout frequency counter (and only for FT-7B); ; FL-110 linear amplifier 10 W in, 90 W out; ; RSL/RSM mobile HF antenna combination consisting of the RSM chassis clamp and 5 antennas for the 80, 40, 20, 15 and 10m amateur bands. 
Title: Dynaco
Content:  Today, Dynaco is best remembered for its highly regarded vacuum tube stereo amplifier, the Stereo 70 (ST 70). Introduced in 1959, the ST 70 was available as a kit (Dynakit) intended for assembly by the purchaser or as a complete factory-wired unit. The ST 70 used four EL34 output tubes, one GZ34/5AR4 rectifier tube, two 7199 input (driver) tubes, two output transformers, one power transformer, and a preassembled printed circuit board (PCB) containing the driver circuit. It produced 35 watts per channel. The driver circuit had a single 7199 pentode/triode tube per channel, and used the driver tube to handle both voltage 
Title: Yamaha SY77
Content:  The SY/TG range as a whole was discontinued sometime between 1995 and 1997. The SY77 and SY99 were replaced as the flagship Yamaha synthesizer workstations by the W7 and W5, respectively. However, the SY77 and SY99 were the last Yamaha "flagship" workstations to be natively capable of the fully fledged FM synthesis that had been introduced with the DX line. Yamaha's later FS1r was the most advanced of their FM synthesizers, adding 8-operator synthesis and formant synthesis (hence FS), but it was a rack-mounted module and never received much attention, and so it was discontinued rapidly, with the result that units today are both hard to find and expensive. Some subsequent products by Yamaha included FM to certain extents. 
Title: Yamaha DX7
Content:  expensive to manufacture due to its integrated circuit chips. At the same time, Yamaha was developing the means to manufacture very-large-scale integration chips; these allowed the DX7 to use only two chips, compared to the GS1's 50. Yamaha also altered the implementation of the FM algorithms in the DX7 for efficiency and speed, producing a sampling rate higher than Stanford's synthesizers. Chowning felt this produced a noticeable "brilliant kind of sound". Yamaha displayed a prototype of the DX7 in 1982, branded the CSDX in reference to the Yamaha CS range of analog synthesizers. In late 1982, Briton Dave Bristow and American Gary Leuenberger, experts on the Yamaha CS-80, flew to Japan to develop the DX7's voices. They had less than four days to create the DX7's 128 preset patches.

Question: gestational sac and yolk sac but no baby at 7 weeks?
Answer: an anembryonic gestation.