[jbh2]

Finally, its a winner, thanks to you Martin.

I got the HK2500 tapedeck up and running. Just new belts then OK. Then I tried my testtape in it, and the tape was full of dropouts, and very bad overall.
Then tested a lot of my old tapes and most of them had dropouts.
(Old tapes loose their megnetism)
But found 2 good ones (99 % good) and gave them to B&O 8004.
Holy moses, it worked. ! Both channels, VU, dolby in/out, timerdisplay. All fine.

(until now, maybe some details isnt working, but so far so good)

So you were right Martin and I was getting “blind” and forgot the testtape, and only focused on the 8004.
Thanks for keeping your interest and continued help. Very grateful and happy.

 

[jbh2]

yes to all.
I will try to find another tape, and also have another tapedeck (working) and will make a new recording on that.

Will a bad/very old tape have that performance, sounds OK a short time, then silence. ?

[jbh2]

Result of checking the 7 volt. Both L and R were 6,89 Volt and the 14 volt is 13,8 Volt.

So I think thats fine. But again, with 50 hz hum on the tapehead, I get fine signal in both channels as long as I will.
Is it possible to connect a sinus signal from a tonegenerator at the tapehead. (input on playback amplifier)

Or do you have any other suggestions I would be happy ?

Thanks again Martin.

 

[jbh2]

No time yet, but will do it soon. Thanks again for fine info,

[jbh2]

The Recording is OK. Only one head. Tape is running perfect on head. Only Playback problem..

[jbh2]

Hi Martin.

I will check the 7v ref. But Dolby is OFF.
Yes the VU follow the sound.

If I gently touch the pins on tapehead, L and R, with my screwdriver I get 50 Hz hum i both.
Very clear, steady and strong signal. No dropout in hum.

[jbh2]

Thank you. I found the 3300 service manual and the schematic. Almost the same as in CDX 2.

The problem was the (too high) positive voltage to motor. ( LID up.) It was 8 volt.
I could not find any defective components, so I added a 15 ohm in series with the collector on the driver transistor to motor. Now it opens very smoothly.

The minus -5 volt was -4,4 v so that worked fine. ( LID down.)

[jbh2]

Hi Martin, thank you for answer. (er du ikke dansk, syntes jeg har set Dillen navnet før ?)

I cant see how LID adjustment is possible, the lid switch is mounted with 2 small screws and it have very little tolerance in holes. I have tried to adjust.

Also the LOAD switch is with 2 screws.

I have seen that its possible in a CDX to adjust LOAD and LASER sw.

There is no LASER sw in a CDX 2 and no MAINS sw,

I need the schematic for a CDX 2, have only one for CDX.

In a CDX the LID motor UP/DOWN voltage must bee +5 volt and -5 volt.
But I have +8 volt and – 5 volt so maybe the +8 volt is too high at makes the crack sound ?

Mvh Jens

 

[jbh2]

problem solved. By lubricating the belt with a little grease and reduce the friction

it works now. Opens and lid stops at top without crakking.

[Author]

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