Thread Rating:
  • 0 Vote(s) - 0 Average
  • 1
  • 2
  • 3
  • 4
  • 5

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



Users browsing this thread: 1 Guest(s)
[-]
Recent Posts
trying to identify this wire type
Thanks to all for the feedback. As Arran said, it is probably an older replacement and yes it has a grid cap so I will ...georgetownjohn — 09:32 PM
trying to identify this wire type
It's possible that the red wire, actually a grid cap lead, is a very old replacement, I can't remember seeing a pre 1939...Arran — 09:18 PM
Gilfillan Brothers Car Radio?
Hi everyone,  Special thanks to Joe Rossi for tracking down this obscure radio and thanks to others who took up the hun...Antipodal — 08:15 PM
trying to identify this wire type
Here's one source for your wire of many. Take care and BE HEALTHY! Gary P.S. Can't get the right color you need? I ...GarySP — 06:40 PM
trying to identify this wire type
...and modern wire of the appropriate gauges and insulation V-rating (300V minimum, usually shown right on the wire) is ...morzh — 05:47 PM
1930s Stromberg-Carlson Tombstone Radio need help identifying model number
I have a question about this radio, is there anyone that has access to this radio that has an intact unmolested speaker ...captainclock1988 — 04:28 PM
1930s Stromberg-Carlson Tombstone Radio need help identifying model number
Well what makes me confuse all of those companies is that all three of those companies (Setchell-Carlson, Stromberg-Carl...captainclock1988 — 04:21 PM
trying to identify this wire type
The red wire is rubber covered wire. The others are cotton braid over rubber often in colors or a tracer, also strand...Chas — 02:43 PM
trying to identify this wire type
Greetings Phorum members, Hope you can help me identify this type of wire in the photo I have attached.  I am not sure ...georgetownjohn — 01:53 PM
Philco 60 Squealing
All correct shields must be in place, all tubes correct no subs of any kind. Check any soldered, riveted ground conne...Chas — 01:24 PM

[-]
Who's Online
There are currently no members online.

>