If I wanted to measure the primary impedance of an output transformer from a tube amp can I load the secondary with the specified load resistor and use the DATS V3 on the primary to give me the impedance or is there a better way?
I've got a transformer that has a 4, 8 and 16 ohm tap. Anyways the 4 ohm tap is supposed to be the center of the winding and I should get equal voltages from the 4 ohm tap and ground and the 4 ohm tap and the 16 ohm tap. The 16 ohm tap has a slightly higher output voltage than the 4 ohm tap.
60Hz sinewave on primary winding.
4 ohm tap to ground 118mVrms
16 ohm tap to 4 ohm tap 127mVrms
Need to measure the primary impedance with a 4 ohm load and then a 16 ohm load so that I can determine if the 16 ohm tap is greater than 16 ohms or if the 4 ohm tap is less than 4 ohms or if it's a combination of both.
I've got a transformer that has a 4, 8 and 16 ohm tap. Anyways the 4 ohm tap is supposed to be the center of the winding and I should get equal voltages from the 4 ohm tap and ground and the 4 ohm tap and the 16 ohm tap. The 16 ohm tap has a slightly higher output voltage than the 4 ohm tap.
60Hz sinewave on primary winding.
4 ohm tap to ground 118mVrms
16 ohm tap to 4 ohm tap 127mVrms
Need to measure the primary impedance with a 4 ohm load and then a 16 ohm load so that I can determine if the 16 ohm tap is greater than 16 ohms or if the 4 ohm tap is less than 4 ohms or if it's a combination of both.
There is no reason you couldn't do it without the hardware, should that be a limitation. Use any similar software like ARTA or REW as a signal generator and plotter. Either measure the transformer against a resistor or resonate it with a capacitor..
The primary is listed as 3.8k plate to plate so would it be better to use a 3.8k resistor on the primary and connect the DATS to the secondary?
Hopefully someone knows.
Otherwise, if you use the RL method and discover at what frequency VL=0.7xVTest , or use a resistor in series with a parallel RC and discover at what frequency they resonate, we can calculate L.
Otherwise, if you use the RL method and discover at what frequency VL=0.7xVTest , or use a resistor in series with a parallel RC and discover at what frequency they resonate, we can calculate L.
I don’t think this will work well for this application. The DATSv3 is designed to measure relatively low impedance speakers. I took one apart a few years back (posted on this forum), it uses a 10k series resistor and assumes any load connected is assumed well below this 10k. For loads is above 100 ohm the error is greater than 1%.
If you just want to know the impedance, use a LCR meter to measure the primary with a given load on the secondary. An added benefit of the LCR meter is you can measure the primary inductance and leakage capacitance to estimate the bandwidth. DerEE makes a very good reasonably priced meter.
If you just want to know the impedance, use a LCR meter to measure the primary with a given load on the secondary. An added benefit of the LCR meter is you can measure the primary inductance and leakage capacitance to estimate the bandwidth. DerEE makes a very good reasonably priced meter.