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38-690 Tweeter Temperature
#8

Based on my measurements and the schematic, you most certainly will have the same issue (if your 38-690 is not modified). You don’t need the IR thermometer, just measure the voltage across the two field terminals (smaller diameter pins) on each tweeter- one will be 40ish volts, and the other 80ish volts. After operating for a few minutes, the 80v one will be warmer to the touch, and hot after 15 minutes.
Voltage across the woofer field will be about 250v, yet cool.


Messages In This Thread
38-690 Tweeter Temperature - by RGK20m3 - 04-21-2022, 08:14 AM
RE: 38-690 Tweeter Temperature - by Brad Winder - 04-21-2022, 09:39 AM
RE: 38-690 Tweeter Temperature - by Ron Ramirez - 04-21-2022, 09:41 AM
RE: 38-690 Tweeter Temperature - by RGK20m3 - 04-21-2022, 09:47 AM
RE: 38-690 Tweeter Temperature - by morzh - 04-21-2022, 02:25 PM
RE: 38-690 Tweeter Temperature - by RGK20m3 - 04-21-2022, 03:35 PM
RE: 38-690 Tweeter Temperature - by Brad Winder - 04-22-2022, 12:11 AM
RE: 38-690 Tweeter Temperature - by RGK20m3 - 04-22-2022, 04:48 PM
RE: 38-690 Tweeter Temperature - by RickC - 11-23-2023, 03:46 AM



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