Situated between the FH-3 and the FH-7 in Sony's 1985 model lineup is this FH-5. It can be considered a 3-piece boombox, as it has detachable speakers and a center section. However, the center section is comprised of multiple pieces itself, assembled together with metal brackets and a quick-detach handle, so it is probably more appropriately called a portable mini component system. Nevertheless, with an internal battery compartment and carry handle, it does indeed qualify as a boombox, although considering its heavy weight and poor ergonomics, you probably wouldn't want to carry it further than from one room to another. It's definitely not a model you would want to walk down the street with, or else you might discover later that one of your arms has become longer than the other! 
Sporting a 3-way APM speaker system, this model is similar in appearance to the FH-7 including the LED lit equalizer slider tips. But instead of the digital tuner, the FH-5 has an analog tuner. Additionally, the FH-7 has separate preamp control and tuner modules whereas the FH-5 has an integrated preamp/tuner control module.
Size wise, this is a very compact system.
This image shows the FH-5 sitting atop the Panasonic RX-CT980, also a 3-piece box. However, while the Panasonic only weighs 1/2 as much as the Sony, the sony is far more compact even given the modular center section. The tape deck is a very high quality deck, and features autoreverse as well as soft logic controls. Sound quality is excellent as befitting all examples of the Sony FH line; sound is very detailed, good solid bass (though not deep), and very sensitive speakers resulting in hall filling volume. This model was offered in silver or black color.
(Some images provided courtesy of Chordeater)
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