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Onkyo TX-28

Quartz Synthesized Tuner Amplifier

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Onkyo TX-28


Tuning range: FM, MW

Power output: 45 watts per channel into 8Ω (stereo)

Frequency response: 20Hz to 30kHz

Total harmonic distortion: 0.08%

Damping factor: 35

Input sensitivity: 2.5mV (MM), 150mV (line)

Signal to noise ratio: 75dB (MM), 95dB (line)

Output: 150mV (line)

Dimensions: 435 x 112 x 343mm

Weight: 7.5kg


service manual   English - nc-stereoman

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Reviewed Nov 17th, 2015 by Kneed2no

I enjoyed this unit. The sound was very good. The controls were well positioned. It did have some problems. The station memory did not hold. I had to replace the super-capacitor. The fuses occasionally blew. Eventually one of the channels died. Now I am looking for another receiver to take its place.

Reviewed Aug 30th, 2015 by guest

All in all a nice and for the most part trouble free receiver.

The only 2 common problems after 30 or so years are the speaker relays (contact problems leading to intermittant audio) and the STK4863 hybrid IC (thermal compound between heatsink and IC breaks down which leads to overheating and frying/shorting)

Fortunately both parts don't cost much to replace in case they go bad and the STK4863 (35W minimum output power) can be replaced with either the original type or compatible ones, some of them being the STK4843 (30W), the STK4853 (30W), the STK4873 (35W), the STK4893 (40W) or the STK4913 (50W).

There are some more compatible models (4833,4813,4803,4793,4773), but all of them have noticeably lower power output (25W...10W) than the 35W minimum of the original part.

In Europe (excl. UK/Switzerland, as far as I know), this model is known as the TX-7330. Why? Only Onkyo knows..



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