Hello,
Recently my uncle gave me faulty Grundig TK-248 portable tape recorder to look at. Tape spins and winds properly but no sound from the speakers, just a faint hum on loudest settings.
As a first step I cleaned the heads with alcohol, no difference whatsoever.
Afterwards I opened the unit and found 0,1A fuse burnt ant the other 1,6A obviously repaired sometimes in the past with a litz wire which passed continuity test.
I replaced a burnt 0,1A fuse and before power up connected a light bulb in series with AC. This time I got sound but light bulb remained fully bright all of time time which would suggest a short in the device if I am not mistaken.
I am attaching schematics, so if you have an idea what to check next I would be very grateful.
Kind regards
Marko
Recently my uncle gave me faulty Grundig TK-248 portable tape recorder to look at. Tape spins and winds properly but no sound from the speakers, just a faint hum on loudest settings.
As a first step I cleaned the heads with alcohol, no difference whatsoever.
Afterwards I opened the unit and found 0,1A fuse burnt ant the other 1,6A obviously repaired sometimes in the past with a litz wire which passed continuity test.
I replaced a burnt 0,1A fuse and before power up connected a light bulb in series with AC. This time I got sound but light bulb remained fully bright all of time time which would suggest a short in the device if I am not mistaken.
I am attaching schematics, so if you have an idea what to check next I would be very grateful.
Kind regards
Marko
Attachments
Check the record/playback switch; clean the contacts.
Replace the 1.6A fuse with the correct rating fuse.
If your lightbulb, in series with the mains power, is less than 100W it will light as these machines draw quiet a bit of power.
Power up on direct mains and observe the fuses. You may find all is OK again.
Replace the 1.6A fuse with the correct rating fuse.
If your lightbulb, in series with the mains power, is less than 100W it will light as these machines draw quiet a bit of power.
Power up on direct mains and observe the fuses. You may find all is OK again.
Hello Joe,
I already cleaned the sliders for the volume on the right, but did not not check the switches, will do.
I currently don't have suitable fuses, but have plenty of resistors at hand, could you suggest a suitable value for quick test. BTW burnt 0.1A fuse had a black glass, not just burned wire inside.
And thanks for quick reply.
Hmm, it was a success, after changing the fuse as JoeSnell recommended music play and very loud at that 
Can life be so simple?
I have a question though, it seems the music played for LEFT channel and one from the RIGHT are not the same, like two different recordings if that makes any sense
Br
Marko
Can life be so simple?
I have a question though, it seems the music played for LEFT channel and one from the RIGHT are not the same, like two different recordings if that makes any sense
Br
Marko
Thank you for that explanation epicyclic, I was wondering about those buttons
and just put it to Stereo thinking it would sound better. One question, can I listen to mono track on both LEFT and RIGHT channel at the same time?
Sorry for the ignorant questions, but I have no manual.
And to answer my own question "Can life be so simple", my enthusiasm because of successful repair was quickly replaced by utter despair when my 9 year old son refused to write his homework, and it all went to **** from there.
So, I guess the answer is NO, it cannot.
I have the TK146. One time I was planning to transform this into a stereo unit by means of cloning the schematics or connecting it to a cassette deck, but then CD's arrived and …
Don't forget to lube the motor and replace the belts or use baby powder on them to soak any grease or oil contamination.
Don't forget to lube the motor and replace the belts or use baby powder on them to soak any grease or oil contamination.
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