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  #1  
Old 08-12-2017, 11:26 AM
Truthseeker14 Truthseeker14 is offline
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Default How many millivolts from a Fishman classic 4t pickup

Hi, I'm new to the forum. I tried searching but didnt' find anything.

I have a Fishman Classic 4t pickup, and the house sound system does not get any signal when I'm plugged in. I don't have an amp at home so I can't test it very well. When I plug my guitar into an external tuner, the tuner picks up the signal and can tell what string i plucked. I measure the voltage when one end of the cable is plugged into my guitar and the other end is attached to a volt meter. When I pluck a string, I get a 0.1 mV reading, which is the limit of my volt meter (i.e., it doesn't measure down to 0.01 mV). When I really strum hard, I get about a 0.3 - 0.4 mV reading. Does this sound like I'm getting enough of a signal from the pickup, and it's an issue with the house sound system? Or is it something about my pickup?

The Classic 4t has an on-board tuner and that works fine.

Thanks
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Old 08-12-2017, 12:53 PM
jonfields45 jonfields45 is offline
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The output should be at least 100 mV (1 volt would not be too high for that test) and something is not right with the guitar or the meter.
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Old 08-12-2017, 08:50 PM
Truthseeker14 Truthseeker14 is offline
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Originally Posted by jonfields45 View Post
The output should be at least 100 mV (1 volt would not be too high for that test) and something is not right with the guitar or the meter.
Thanks, what do you mean that "1 volt would not be too high for that test"?
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Old 08-13-2017, 06:30 AM
jonfields45 jonfields45 is offline
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Guitar pickup level inputs to most amps are designed to handle a 1 volt RMS signal more or less. If you were to read 1 volt in your test it would be about what I would expect. However quieter pickups will be in the 0.1 volt range.

When you said your tuner works, I would suspect the wiring from the preamp to the output jack, or the output jack itself. If you are up to it, you can see if removing that connection (I don't know if it is screw contacts or plugs) cleaning the ends with contact cleaner by spraying a cotton q-tip and using the q-tip to wipe the contacts (DeOxit is the name brand but the stuff at Home Depot is fine as long as you don't use it for Pots which are not metal-metal contacts).
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Last edited by jonfields45; 08-13-2017 at 06:39 AM.
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Old 08-13-2017, 01:39 PM
Truthseeker14 Truthseeker14 is offline
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Well, it works. I simply changed batteries in the Fishman pickup and the house sound system picked up the signal just fine. There was no "low battery" reading on the Fishman (which is a feature for this one), but the voltage in the old battery was 8.9 volts. I replaced it with a fresh one which read around 9.1 volts and it works now. The voltage coming from the pickup, however, still read very low (0.1 mV), so I'm not sure what was happening there.
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Old 08-14-2017, 05:39 AM
jonfields45 jonfields45 is offline
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Quote:
Originally Posted by Truthseeker14 View Post
Well, it works. I simply changed batteries in the Fishman pickup and the house sound system picked up the signal just fine. There was no "low battery" reading on the Fishman (which is a feature for this one), but the voltage in the old battery was 8.9 volts. I replaced it with a fresh one which read around 9.1 volts and it works now. The voltage coming from the pickup, however, still read very low (0.1 mV), so I'm not sure what was happening there.
Maybe your meter needs a new battery too.... BTW, a battery tester that loads the battery is much better than a standard meter. You can get an analog one at Home Depot for less than $10. I have both of these and they are excellent:

https://www.bhphotovideo.com/c/produ...er.html?sts=pi

https://www.bhphotovideo.com/c/produ...er.html?sts=pi
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  #7  
Old 08-15-2017, 09:45 AM
irvine irvine is offline
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Quote:
Originally Posted by Truthseeker14 View Post
Well, it works. I simply changed batteries in the Fishman pickup and the house sound system picked up the signal just fine. There was no "low battery" reading on the Fishman (which is a feature for this one), but the voltage in the old battery was 8.9 volts. I replaced it with a fresh one which read around 9.1 volts and it works now. The voltage coming from the pickup, however, still read very low (0.1 mV), so I'm not sure what was happening there.
When measuring the output of the pickup be sure the meter is set to AC, not DC as for measuring the battery voltage.
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