In Reply to: RE: update 2 posted by vinnie2 on February 18, 2019 at 18:14:21:
"In the morning I will see if I can set the scope to measure AC instead."
I shan't even try guessing what you mean by that.
There's nothing wrong with measuring peak-to-peak voltage of the sine wave; just divide by (2 * sqrt2) (which is about 2.83) to get the RMS voltage, like I said.
But the answer you got seems to be coming out to be much too large, implying 36 watts into 8 ohms, which just isn't believable for a single-ended amplifier like you have built. So there is evidently something wrong with your interpretation of what you are seeing on the scope. (Misreading the volts per division setting?) Or else something wrong with the scope?
You could practice by checking the output of your signal generator on the scope, and comparing the peak-to-peak voltage (divided by 2 * sqrt2) with the rms voltage you measure with a digital voltmeter. Do those two results agree, within expected experimental errors?
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Follow Ups
- RE: update 2 - cpotl 19:57:17 02/18/19 (35)
- RE: update 2 - vinnie2 04:58:32 02/19/19 (34)
- RE: update 2 - cpotl 06:07:46 02/19/19 (0)
- RE: update 2 - cpotl 05:40:56 02/19/19 (32)
- RE: update 2 - vinnie2 07:00:18 02/19/19 (31)
- RE: update 2 - deafbykhorns 15:15:55 02/20/19 (30)
- RE: update 2 - Tre' 10:12:50 02/22/19 (0)
- much better! - vinnie2 06:21:16 02/22/19 (24)
- RE: much better! - cpotl 08:42:38 02/22/19 (23)
- RE: Sample Sine Wave - deafbykhorns 11:28:41 02/22/19 (20)
- 845 op points - vinnie2 06:19:57 02/23/19 (0)
- RE: Sample Sine Wave - vinnie2 05:02:59 02/23/19 (15)
- RE: Sample Sine Wave - deafbykhorns 16:51:37 02/23/19 (14)
- RE: Sample Sine Wave - vinnie2 17:56:28 02/23/19 (13)
- RE: Grid Current - deafbykhorns 14:56:39 02/24/19 (7)
- RE: Grid Current - vinnie2 17:59:00 02/24/19 (6)
- RE: Grid Current - deafbykhorns 06:00:36 02/25/19 (5)
- RE: Grid Current - vinnie2 06:44:26 02/25/19 (4)
- RE: Try the 300B with a good DHT - deafbykhorns 07:54:02 02/25/19 (3)
- RE: Try the 300B with a good DHT - vinnie2 09:19:20 02/25/19 (2)
- RE: Try the 300B with a good DHT - deafbykhorns 13:01:02 02/25/19 (1)
- thanks! nt - vinnie2 13:59:12 02/25/19 (0)
- what are the 6sn7 op points? (nt) - Tre' 06:53:46 02/24/19 (4)
- RE: what are the 6sn7 op points? (nt) - vinnie2 14:45:14 02/24/19 (3)
- RE: what are the 6sn7 op points? (nt) - Tre' 18:02:17 02/25/19 (2)
- RE: what are the 6sn7 op points? (nt) - vinnie2 04:31:51 02/26/19 (1)
- RE: what are the 6sn7 op points? (nt) - cpotl 05:07:07 02/26/19 (0)
- good post (nt) - Tre' 14:06:08 02/22/19 (0)
- RE: Sample Sine Wave - vinnie2 11:40:25 02/22/19 (1)
- RE: Sample Sine Wave - Tre' 14:05:06 02/22/19 (0)
- Good point. - Tre' 10:43:36 02/22/19 (0)
- RE: much better! - vinnie2 09:56:27 02/22/19 (0)
- RE: update 2 - vinnie2 06:23:22 02/21/19 (2)
- RE: Example - deafbykhorns 12:38:17 02/21/19 (0)
- RE: update 2 - cpotl 08:29:18 02/21/19 (0)
- RE: update 2 - vinnie2 17:54:53 02/20/19 (0)