08-06-2008, 12:18 AM
I got my 38-690 up and running but there's no sound at all coming out of the tweeters. (The woofer sounds awesome.) It has the 4.7 uF cap in place of the stock 1 uF, and I played with the phasing. I troubleshooted all the connections and they seem OK. The 4.7 uF cap tests OK on my Fluke meter. The field coils and voice coils of both tweeters seem to measure fine with an ohmmeter. The resistance of the secondary of the output transformer to the tweeters measures 2.8 ohms. Does that sound like it's in the ballpark?
If the tweeter secondary is shorted, I'm assuming I'll never find a replacement transformer since it's an unusual design that also feeds the woofer. I could try to wire a separate output transformer to the tweeters in parallel with the original, but I wonder how that would work without messing up the feed to the woofer. Anyway, I hope the transformer is OK.
Does the 2.8 ohm measurement seem correct for the tweeter secondary? I'm kind of at a loss as to why there's no sound from the tweeters.
Thanks,
Bob
If the tweeter secondary is shorted, I'm assuming I'll never find a replacement transformer since it's an unusual design that also feeds the woofer. I could try to wire a separate output transformer to the tweeters in parallel with the original, but I wonder how that would work without messing up the feed to the woofer. Anyway, I hope the transformer is OK.
Does the 2.8 ohm measurement seem correct for the tweeter secondary? I'm kind of at a loss as to why there's no sound from the tweeters.
Thanks,
Bob
