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Braun tube rc56uk

C

Cbslay

New Member
Hi. I am new here. Having trouble with a Braun receiver from a console. Receive am and fm but the volume has to be max and the loudness is normal. About 1.5 volts at max. Stumped for 2 weeks. Tubes test good. Capacitors replaced. Any suggestions on what to do?
 
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Hi and welcome. Is this the unit: http://www.antiqueradios.com/forums/viewtopic.php?t=134906 ? Was it working before?

The Radio Museum website may be able to get you a schematic. http://www.radiomuseum.org/r/braun_radio_phonograph_rc56uk.html It sounds like something in the audio amplification stage. You can test this by feeding an audio signal via a pot and 0.1uf cap directly into grid 1 (pin 2) of the output stage. I'm assuming a single ended amp here, something like this one: http://oldtech.net/German/7000-USA.gif

Or this AM schematic may help: http://antiqueradios.com/gallery/main.php?g2_view=core.DownloadItem&g2_itemId=111932
 
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Dandy said:
Hi and welcome. Is this the unit: http://www.antiqueradios.com/forums/viewtopic.php?t=134906 ? Was it working before?

The Radio Museum website may be able to get you a schematic. http://www.radiomuseum.org/r/braun_radio_phonograph_rc56uk.html It sounds like something in the audio amplification stage. You can test this by feeding an audio signal via a pot and 0.1uf cap directly into grid 1 (pin 2) of the output stage. I'm assuming a single ended amp here, something like this one: http://oldtech.net/German/7000-USA.gif

Or this AM schematic may help: http://antiqueradios.com/gallery/main.php?g2_view=core.DownloadItem&g2_itemId=111932
Click to expand...
 
Thank you for your reply. The model is rc57uk. It still has the long black rectifier. Thinking this is the problem after talking to someone locally. Should be 300 volts at output and only getting 178. Will drop by RadioShack for the 4 pin 2 amp 400 volt diode and 100 ohm 10 watt resister. Really hope this is it. A beautiful unit I'd like to have working.
 
I do have the schematics for a later model that is very similar to the 1957 model I have. I will check all voltages and thanks. Good to replace the selenium rectifier in any case. Off to RadioShack...
 
That link on Antiqueradios you sent is the correct picture of what I have. I change the rectifier but still have the low volume. Voltages look good. Wonder if the fault is in the FM IF amp. I noticed that when I touched a screw driver to a few of the resisters the sounds goes off. It has the small coil rods. A few flat capacitors inside.
 
Dandy, thanks for the AM schematics. That is the one I will use and refer too. A lady had it in storage. Bought from the original owner. The fuse contacts had corrosion and needed a general clean up. When it came to life the low volume existed. Will include a pic of the FM IF amp.
 
image.jpeg The coil on the left second from top produces a dead sound when I put a screwdriver near the grounding area.
 
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