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Franc Zabkar Franc Zabkar is offline
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Default Grundig AM/FM portable "Transistor 305" troubleshooting

On Sun, 4 Mar 2012 19:47:09 -0800 (PST), klem kedidelhopper
put finger to keyboard and composed:

http://dl.dropbox.com/u/65394789/Gru...0schematic.pdf

Voltage readings
Test point Radio working: Radio not working
------------------- --------------------
E. AF178 -1.10V -1.20V
B. AF178 -1.50V -1.50V
E. AF124 -1.10V -1.20V
B. AF124 -1.32V -1.44V
E. AF121 -0.85V -0.90V
B. AF121 -1.20V -1.30V
E. AF126 (1) -1.00V -3.70V *
B. AF126 (1) -1.20V -4.00V *
E. AF126 (II) -0.80V -3.70V *
B. AF126 (II) -1.10V -3.60V *
E. AC151 (I) - 0.90V -0.80V
C. AC151 (I) --3.05V -2.95V
E. AC151 (II) --0.66V -0.62V
C. AC151 (II) --3.20V -3.10V


I suspect that C45 (near pin #8 of 7209-301) may be shorting.

- Franc Zabkar
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