Schematic for Sony 70ES ?

[TroelsM]

Hi!

I'm looking for the schematic and/or the service manual for this old Sony amp.

Tried Google with no luck.

Regards TroelsM

[Nigel Goodwin]

Originally posted by TroelsM
Hi!

I'm looking for the schematic and/or the service manual for this old Sony amp.

Tried Google with no luck.

Regards TroelsM

How about posting the full model number?, that isn't a Sony model number.

[TroelsM]

sorry... forgot a zero... it's called Sony 700ES.

Regards TroelsM

[Nigel Goodwin]

Still not a Sony model number?, they all start with letters not numbers!.

[TroelsM]

here's a pic of the little beauty:

Regards TroelsM

[es44]

Hi Troels.

You might be lucky at: Sharefx
Requires you to become a member, but it's for free. Then just make a request.
I know for sure, that there's a lot of schematics for older gear, even though at first sight it looks like it's only for newer stuff

Best regards ( og ha' en go' dag )

Ebbe

[Nigel Goodwin]

Originally posted by TroelsM
here's a pic of the little beauty:

Regards TroelsM

The model number is on the bottom right hand corner of the front (as you look at it), but the picture is too small to read it.

Are you wanting to know something specifically about the amp?.

[TroelsM]

Hi Nigel.

Found it! : Sony TA-F700ES

I might buy an old defect 700es, but without a schematic repair is gonna be a real pain.

BTW: I found a ref that says that each output is 2 pairs of Sanken A1186/C2897.... looking at the datasheet I would say that those trannies are a bit to small for +100W/8Ohm. Opinions?

Regards TroelsM

[Nigel Goodwin]

Originally posted by TroelsM
Hi Nigel.

Found it! : Sony TA-F700ES

I might buy an old defect 700es, but without a schematic repair is gonna be a real pain.

The manual isn't on Sony Assist (although the model is listed there), and I don't have a paper manual either.

Do you know what's wrong with it?.

BTW: I found a ref that says that each output is 2 pairs of Sanken A1186/C2897.... looking at the datasheet I would say that those trannies are a bit to small for +100W/8Ohm. Opinions?

The 2SA1186 is rated at 150V, 10A, and 100WC - looks pretty good to me for a 100W/8ohm domestic amp?. The 2SC2897 isn't listed in Towers, but I presume it's the complement to the 2SA1186?.

[TroelsM]

Hi Nigel.

Yes its rated at 1oA/150V/100W, but the SOA is not very impressive. I think the amp is somewhere around 125W/8Ohm and that would take a PSU giving +/-50-55V. Thats 100-110V total... If I'm not reading the SOA-chart the wrong way, then the poor little transistor is getting a bit stressed at 110V when it's passing a few amperes...

All this is probably "normal" in consumer/domestic amps, but this was a pretty expensive amp (I think).

I don't know whats wrong with the amp, but with a little luck it's only the PSU thats bad.

Regards TroelsM