The NES-101 model of the Nintendo Entertainment System (informally known as the NES 2, the top-loading model, or simply the Top Loader) is a compact, top-loading redesign of the original Nintendo Entertainment System control deck and game controllers released byNintendo in 1993.
Nintendo marketed the NES-101 model as the Nintendo Entertainment System Control Deck, exactly the same as the original NES-001 model, only with a "new design" logo on the packaging. It retailed in North America for US $49.99 (equivalent to US $75.00 today). This was at a significantly lower price than the already released Super Nintendo Entertainment System. The NES-101 model is stylistically similar to the HVC-101 model of the Family Computer, which was released in Japan at roughly the same time, but differs in a number of its specifications. The NES-101 controller design is very similar to the Super Nintendo controller. The major differences are that it has two buttons instead of four, no L and R buttons, and is thinner in the middle. This controller, due to its shape, is often nicknamed the "dogbone" or "doggie" controller.
Control Deck (model NES-101)
The external appearance was greatly overhauled and restyled to align its looks to the North American Super Nintendo Entertainment System and to address a number of commonly cited ergonomic problems of the original NES-001 model. The case design was by Lance Bar, who also designed the NES-001, the SNS-001 and the SNS-101 case. The power and reset buttons, while never a problem with the original design, now matched the curvature of the new look. The NES-101 does not have an LED power light to indicate the unit is on, as the original NES-001 and SNS-001 included.
The most obvious change in the redesign was the removal of the ZIF cartridge-loading system that caused trouble in maintenance and game-swapping when using the NES-001 model. In that system, the user had to first open the lid of the case, slide in the cartridge, then press it down. The large space inside allowed plenty of room for dust to settle and the contact heads were almost impossible to access and clean without unscrewing the case or using the official cleaning kit. Wear and tear was another problem; with continued use, the precision of the mechanism deteriorated and the user would have to poke and nudge at the cartridge to move it to a position that would be read correctly. The NES-101 returned to the standard top-loading method, used by almost all cartridge systems before and since for its ease and reliability.
The design of the game controllers was changed. These were officially known as NES-039 model controllers and informally known as "dogbone" controllers. They were packaged with the system and also sold separately. The controllers were restyled to resemble the SNES controller, with rounded edges that fit more ergonomically in the hands than the old rectangular design (NES-004). The NES-039 model controller does not fit in R.O.B.'s controller slot because of this ergonomic change. The A and B buttons were also set at an angle to mimic the SNES controller as well as provide better ergonomics. The original NES-004 controllers and the NES-039 design are interchangeable between the original NES-001 model and the NES-101 model.
The 10NES authentication chip was completely removed from the system in an effort to eliminate the blinking red power light problem associated with it in the NES-001 model control deck. The removal of the 10NES chip also allows the system to play games that are unlicensed and/or from different regions such as Europe, something an unmodified NES-001 model control deck cannot do.
The RCA composite video output jacks were removed from the system as well; an RF connection is the only way to connect the system to a television unless you have the console modified to add composite output. The original video amplifier circuit path on the motherboard was poorly designed and created faint black lines in the game image.
Family Computer (model HVC-101)The AV Famicom
The HVC-101 model of the Family Computer was a redesign of the original Family Computer video game console released by Nintendo in Japan in the early 1980s. Nintendo itself marketed simply as the Family Computer, exactly the same as the original, but users called it AV Famicom or New Famicom to distinguish from the original. It was released in Japan on December 1 1993 and retailed for ¥6800. Like the original model, it is commonly referred to by the nickname "Famicom". It was stylistically similar to the NES-101 model released in North America at roughly the same time.
The HVC-101 model was designed to address two major design flaws of the original HVC-001 model. The original HVC-001 featured hardwired game controllers; users who wished to add additional, specialized controllers were forced to make use of the deck's single expansion port. In bringing NES-style removable controllers to the HVC-101 model, Nintendo removed the microphone which had been originally included on the second controller in place of the "start" and "select" buttons. The microphone was originally intended to introduce extra functionality for certain games, but, in practice, very few games had ever made use of it. The redesigned controllers have the Nintendo part number HVC-102 and are equivalent to the NES-039 controllers for the NES.
Secondly, the HVC-001 model featured audio/video output via RF modulator only. By the early 1990s, many Japanese television sets featuredcomposite input jacks. The HVC-101 replaced the HVC-001's RF output switch with composite AV cables, thus the name AV Famicom. This represented the biggest difference between the Japanese HVC-101 and the North America NES-101, which included only RF modulator output functionality (even though the original NES had composite as well as RF modulator outputs).
The HVC-101 also featured a slightly different case design from the NES-101 in order to allow compatibility with the Family Computer Disk System. The area around the cartridge slot of the HVC-101 is flat rather than convex. This allows users to insert the large RAM Adapter Cartridge required to use the Disk System accessory.
There are two known revisions of the NES-101; both have redesigned circuit boards that improve video output quality. The first has a Nintendo AV Multi-Out port (the same one built on the Super NES,Nintendo 64, and GameCube) that replaces the RF jack completely. The other looks exactly the same as the rest with the RF video output jack and channel select switch, but with excellent video output quality. These versions were replacements for those who sent their original NES-101 systems to Nintendo with a poor quality video complaint.  These models are extremely rare (and in fact their existence was not discovered until a few years ago) as they all came as replacement units from Nintendo., but some claim that the revised AV model was in stores near the end of its lifespan.