Re: Latest Acquisition - Grundig TK 14
Measured the signals at the heads. Same 240V p-p at erase head and 500V p-p at Record head (1,000V into C19 trimmer dropped down to 500).
As before seemed too high. Spec for erase voltage is 70V rms and record bias 155V rms, I must remeasure using my FET VOM.
By Peak to Peak calculation conversion to rms, 240 = 85 and 500 = 177, so my results are somewhat high, but not as high as I had originally assumed.
The heads have good continuity resistance.
I now need to recheck recording & erase to see if they still do not work.
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