KENWOOD L-07 CII preamp

[dray177]

It's my first thread here.

I have a Kenwood L-07 CII with a problem on the right input phono MC stage ( noisy with cracking... ).
But without diagram impossible to repair.
And also impossible to find service manual, schematic, information about, ...

Please I need your help !
Raymond

My preamp :

[aparatusonitus]

Hi and wellcome to forum dray177,

I've just being given a schematic for L-07C model, so you can send me a pm via forum with your private email so I can send.

[dray177]

Originally Posted by aparatusonitus

Hi and wellcome to forum dray177,
I've just being given a schematic for L-07C model, so you can send me a pm via forum with your private email so I can send.

Ooooooooh !!!
Thanks Aparatusonitus for your nice intention.
My address : dray177@aol.com

Raymond

[aparatusonitus]

Check your email ;-)

[tiefbassuebertr]

Originally Posted by dray177

It's my first thread here.

I have a Kenwood L-07 CII with a problem on the right input phono MC stage ( noisy with cracking... ).
But without diagram impossible to repair.
And also impossible to find service manual, schematic, information about, ...
Please I need your help !

Hallo, Raymond
You still remember to me (Mark Levinson No. 23)?
I have had the complete Service Manual from Kenwood's L-07 CII (original printing, not copy), but until this day I don't find it.
But I recall, that I have order it there:

Schaltungsdienst Lange oHG
Impressum: Schaltungsdienst Lange oHG
Zehrensdorfer Str. 11
12277 Berlin-Marienfelde
Tel.: ++49 (0) 30 / 723 81-3
Fax: ++49 (0) 30 / 723 81-500
info@schaltungsdienst.de

Regards
Andreas

P. S.: very fine website:
http://www.wtconcept.com/levinsonml2/

[dray177]

Originally Posted by tiefbassuebertr

Hallo, Raymond
You still remember to me ( Mark Levinson No. 23 )?
I have had the complete Service Manual from Kenwood's L-07 CII (original printing, not copy), but until this day I don't find it.
... ...
Regards
Andreas

P. S.: very fine website:
levinsonml2

Hello Andreas

IMPOSSIBLE !!! I will never forget my best friends
And discuss with you about Levinson gear as ML-1 faulty line modules, ...

What a pity you don't find your SM L-07CII.
Aparatusonitus very kindly ( again many thanks ! ) send me the L-07C schematics.
But a bit very different with MKII model.
And still, I never found these faulty components in the right MC phonostage of my preamp !

In fact, would L-07CII be more difficult to repair than a Levinson ML-2 ???

Raymond

[tiefbassuebertr]

Originally Posted by dray177

In fact, would L-07CII be more difficult to repair than a Levinson ML-2 ???
Raymond

No.
.....on the right input phono MC stage ( noisy with cracking... ) ???

At first you must perform a failure isolation.
If there are switches to select the input impedance and gain factor, remove it and solder wires to get the neseccary values (no longer non linear transition resistance there are)

Now check out and compare the behavior with
- open input
- short input and
- normal input connection to your moving coil cartridge.

What happens? Is sound to hear? Or only noisy with cracking (flicker noise, shot noise)? Then there is a complete break in the signal line.

Are there a reaction by a slightly mechanical strain to the j-FET's and BjT arround the MC head amp?

If yes, and there are no bad soldering in this aera, the internal bond wire of the transistor itself has temporary interruption or unwanted transition resistance.

What about the color of the MC head amp transistor pins (black or silver)?
If you try to find schematics by google, uses different spelling
"L 07CII" "L07C II" "L07CII" "L 07C II" "L 07 C II" "L07 C II" both "Trio" and "Kenwood" for second keyword.

Here are some Links:
TRIO ƒRƒ“ƒgƒ��[ƒ‹ƒAƒ“ƒvL-07CII‚ÌŽd—l ƒgƒŠƒI
TRIO/KENWOOD ƒZƒpƒŒ�[ƒgƒAƒ“ƒv/‚»‚Ì‘¼ƒAƒ“ƒvˆê—— ƒgƒŠƒI/ƒPƒ“ƒEƒbƒh
review33.com - 影音天地
Kenwood L-07C-II, Hifi-Klassiker - HIFI-FORUM
and attachements:

[zeonrider]

Here is!

Regards zeoN_Rider

[dray177]

Originally Posted by dray177

... ...
In fact, would L-07CII be more difficult to repair than a Levinson ML-2 ???
Raymond

NO !!! L-07CII a bit less complex than Levinson ML-2

Yesterday failure was solved.
In fact only ( I don't know which one ) a bad solder on the mother board ( a double-side one ) and the solution was to re-solder on the two faces all components on the MC stage.

But without your help, Aparatusonitus and Tefbassuebertr, I think I lost my footing !

Raymond.

About my work on ML-2 amps :
http://www.wtconcept.com/levinsonml2/

[aparatusonitus]

Good work Raymond...now enjoy your preamp!