I have a Technics SA - DX750 Amp Everytime I turn it on I get an error message F70 and then it requests that I turn the power off. This is all it does now, so sound. How do I solve this issue I have not checked the fuses inside. Thank you, Lynne

Help in the link

https://www.google.com/search?q=technics+sa-dx750+f70+error

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This may be blown fuze. This is an informative forum. Read answer one-third down page. Hope this helps Technics stereo receiver F70 error code CK5 Forums

bad powersupply.

I have a technics sa dx 750 receiver that cut...

According to Technics reference manual, turn the unit off, unplug for a few, plug in, turn unit on. Consult your "dealer"(authorized repair person, i guess) if light remains on. But doesn't say what f70 means, or associated with.
Unplug and open up the unit, and check the internal fuses on the circuit board. Also check for proper speaker wire hook up. Re-seat the connections. Visibly check the speaker wire runs for shorts, cracked casing, cat/dog chewing. etc.

Hope this helps.

The question is what is causing the overload? The power supply or the output devices on the heat sink?
If you have accidently shorted a speaker wire, then the answer will be output devices, otherwise it could be anything in the power section. You may find a burnt or damged device with either of the causes.

SA-DX750 (sister Model to SA-DX850). Showing error code F70, after a few minutes running. Checking the power rails revealed +5VA and +5VD, on the Digital Circuit Board 'A', dropping to about 2V, when fault occured. F5, T1A, on the Sub-Transformer Circuit 'M', was subject to occasional blowing. The problem was traced to an intermittent break, in the printed circuit board conductor, in the vicinity of Q1702 (+5VD regulator) collector, on the Digital Circuit Board 'A'.. Repairing this cured the problem. Note that removing F5 (above), or disconnecting CN702, CN1000A or CN904B, on the Digital Circuit board 'A', also causes this error code to be displayed. Failure of the audio output ICs, IC651 & IC801, is apparently the usual reason for this error code being dsiplayed, but it is worth checking the power rails viz. +/- 25V (Fuses F3 & F4, T6.3A, on Sub-Transformer Circuit 'M') +/- 55V, +/- 14V etc.

Technics sadx750 and says f70 and turn power off

You must have air flow through this unit!...accordianman

F70 means Blown Internal Fuse change the internal fuse and that should solve the problem if not you may have to change the output