Checking pickup output

**Woody Sound** · 07-03-2024, 10:35 PM

Caveat: electronically challenged here. Is there any way to check the output of a hb pickup right on the pickup with a multimeter? IOW, not from the end of the lead cable.

**sgosnell** · 07-03-2024, 11:42 PM

You can check the output voltage at the output jack, or at the other end of a cable. It won't be high, just millivolts. However, you may mean the pickup resistance, which is not the output. For that, you need to have the pickup disconnected from the pots, which will introduce their own resistance into the circuit.

**Franz 1997** · 07-04-2024, 05:48 AM

Originally Posted by sgosnell

You can check the output voltage at the output jack, or at the other end of a cable. It won't be high, just millivolts. However, you may mean the pickup resistance, which is not the output. For that, you need to have the pickup disconnected from the pots, which will introduce their own resistance into the circuit.

The advice here is correct, but it's a significant hassle to de-solder a pickup from the harness and then re-install it. You can get an approximation of the dc resistance of the pickup by measuring at the output jack, and then taking into account the resistance of the volume pot. The tone pot should have no effect unless it's faulty, as it has a blocking capacitor in circuit. Usually the volume pot is either a 250K on Fenders, ot a 500K on Gibsons and similar guitars. ( Some 70s Gibsons have 300K pots). Turn the volume control to max, and the switch to only the pickup concerned.. So, if the resistance of the pickup is - for example- 10K, your reading will be slightly lower than 10K by a factor of approximately 2%, ( one fiftieth) assuming a 500K volume pot. Obviously it would be approx 4% in the case of a fender 250K pot. This is inexact, but good enough to approximate the real pickup resistance, with a roughly known margin of error. Even accounting for the possibility of 300K pots as on some Gibsons, it's good enough to check continuity, for example. As an example, a late 60s T top gibson HB, which has a real resistance of around 7.5k, will read around 7.3K at the output jack, using this method.

If what you want to get is the pickup voltage output, as noted above, you need a meter that reads millivolts. It's very hard to get any meaningful data this way, other than to tell that the pickup is working, as other factors like inductance are not easily measureable. The ear test is usually more useful...