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Technics Tape-Deck Service Manuals?

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Hoca

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technics rs-b905

Hi

I'm trying to get hold of three Technics tape deck manuals...

RS-B905 (I need this one the most!)
RS-B755
RS-M233X
RS-B965


Any help would be useful, even if it's only a schematic.

It would be great if someone knows of a download location to grab free PDF versions of the above manuals?

For that matter, do you know of anywhere that has free-PDF service info for ANY Technics tape decks?

As you can see from the list I'm building up quite a collection of decks, so who knows I may end up with other models too!! :)

Even if Technics decks don't always sound the best they're some of the most stylish decks around! ;)

Cheers in advance

Alan

colly(at)cheerful.com
 

rs b965

RS-B965 instruction manual
 

technics rs-b755 service manual

Thanks for your reply CHINATSMFL, but I already have the instruction manual for this deck.

It's actually SERVICE manuals or schematics diagrams that I'm looking for.

Can anyone help please?
 

rs-b905

Hoca said:
Thanks for your reply CHINATSMFL, but I already have the instruction manual for this deck.

It's actually SERVICE manuals or schematics diagrams that I'm looking for.

Can anyone help please?
 

Here it is ;)

I have this deck, also made some modifications in the original circuit. If you have any questions, I'll be glad to help you.
 

Thank you Board_Man for posting the required service manual!

Do you mean 'YOU' have modified the original circuit? I would be interested in knowing what you have done? :)

Very good of you to reply to an old post :)

Cheers
 

Hoca said:
Thank you Board_Man for posting the required service manual!

Do you mean 'YOU' have modified the original circuit? I would be interested in knowing what you have done? :)

Very good of you to reply to an old post :)

Cheers

Sorry for my late reply. Actually I made some circuit modifications to the original schematic. First of all, I changed some capacitors to boost the low-frequency response to 15Hz. I modified BIAS regulator because the original circuit switch it off on metal position. Adding some capacitor for extremely phase compensation on the input corrects perfectly the phase difference to the high frequency signals. The DBX circuit on play was corrected, too. Since the original circuit has no individual level regulator (the level regulator is common both for dolby and dbx) it was small level difference on playing on dbx. That may corrects by record level dbx regulators, but at all, the record on the tape do not has equal magnetic level for both channels.
The main difficult component replacement was in the recording EQ, where I changed some values of the components for flat response in case of equal bias settings for both channels. The original circuit in my machine has small bias current on one of the channels to compensate the problems in the rec eq. So, when I fixed the rec eq, now the bias was corrected to be equal for both channels.
Adding a additional RC filter only for normal tape to the input of the REC AMP, fixes another problem – the original schematic does not have this circuit, thus the frequency response for normal tape has no good linearity. Adding the circuit makes the middle-range to be on same level with low and high range components.
 
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    Pavel.

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Thank you for your reply.

Do you feel your modifications are reproducible?

Have you kept records of the component changes? if so could you please post those details please?

It would be interesting and useful to see which components you have had to change to receive the results you have been aiming towards.

Cheers
 

Hi everyone i'm new to this forum .. hm and just found this old thread .. i'm not into repairing much .. more into sdiy .. whenever i'm lucky to make something work .. anyway i'm looking for this exact manual RS M233X so i thought if maybe someone can help me somehow .. thanks anyway hope you have a good weekend
greetings
Vladosh
 

Hi Board-Man,
thx for the good scan quality!
K.
 

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