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 Saba Freiburg 14
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 Return to top of page · Post #: 1 · Written at 6:00:17 PM on 9 July 2019.
Mccipolla's Gravatar
 Location: Sydney, NSW
 Member since 9 July 2019
 Member #: 2361
 Postcount: 2

Hello Everyone, I have a Saba Freiburg 14 which has been in my family for as long as I can remember. All appears to function correctly except that the sound coming from one of the channel is muffled/distorted. I have tried to connect an external speaker to determine if the problem is with the actual radio or speakers. The problem is also there when connecting external speakers.

I know it's a shot in the dark but if anyone has some information (schematics) or any pointer as to which part/area of the radio is likely to be at fault to narrow things down, that would be much appreciated.

Thank you.
Marc


 
 Return to top of page · Post #: 2 · Written at 9:26:05 PM on 9 July 2019.
Rudolf's Gravatar
 Location: Brisbane, QLD
 Member since 18 September 2010
 Member #: 739
 Postcount: 71

Hi Marc you can download the service manual for free here.

https://elektrotanya.com/saba_freiburg_14_breisgau_14_continental_sm.pdf/download.html


 
 Return to top of page · Post #: 3 · Written at 9:30:13 PM on 9 July 2019.
Marcc's avatar
 Location: Wangaratta, VIC
 Member since 21 February 2009
 Member #: 438
 Postcount: 3510

If the speakers on the left behave the same when fitted to the right, they are not the problem.

Clearly one amp has failed. Do not tamper with the working one, as circuit, or not it can be used to determine where the other one has failed.

Radio Museum has circuit. https://www.radiomuseum.org/r/saba_freiburg_vollautomatic_14.html

With the number of tubes it has it will help warm a room. ELL80 is possibly a push pull amplifier & if all, or one half of that has issues it will distort.

Being of sixties vintage it will likely need checking to see what sort of capacitors it has in it. If they are of the "Waxed paper" type most are failing or have by now.

Marc


 
 Return to top of page · Post #: 4 · Written at 9:43:26 PM on 9 July 2019.
Marcc's avatar
 Location: Wangaratta, VIC
 Member since 21 February 2009
 Member #: 438
 Postcount: 3510

Obviously two of us writing at the same time: If you are not familiar with German circuits, have a look at it and say to yourself "Why haven't we got circuit diagrams like that?"

Fixing would be a whole lot easier even with a massive animal like that.


 
 Return to top of page · Post #: 5 · Written at 6:19:25 PM on 10 July 2019.
Mccipolla's Gravatar
 Location: Sydney, NSW
 Member since 9 July 2019
 Member #: 2361
 Postcount: 2

Thank you so much Marc and Rudolf Smile


 
 Return to top of page · Post #: 6 · Written at 9:51:09 PM on 10 July 2019.
Marcc's avatar
 Location: Wangaratta, VIC
 Member since 21 February 2009
 Member #: 438
 Postcount: 3510

Having one good amp & one bad is a luxury enhanced by the availability of a circuit. .

As it is working in some sort of ghastly fashion, my approach, as I have them, would be to feed a clean modulated tone into the front end, using a signal generator and then plod through the amp with an Oscilloscope to spot at which point the signal falls apart?

At this point, little time & no money has been spent on repairs.

Marc


 
 Return to top of page · Post #: 7 · Written at 1:54:08 PM on 12 July 2019.
Tallar Carl's avatar
 Location: Latham, ACT
 Member since 21 February 2015
 Member #: 1705
 Postcount: 1315

[Comment deleted: Irrelevant]


 
 Return to top of page · Post #: 8 · Written at 8:20:01 PM on 12 July 2019.
Marcc's avatar
 Location: Wangaratta, VIC
 Member since 21 February 2009
 Member #: 438
 Postcount: 3510

Forgot: As there is a circuit and a working amp; voltage comparisons on the elements of the valves are very important.


 
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