recommend inexpensive digital multimeter for ohms and bias

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demondestroyer

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Just bought a cen tech 11 function digital multimeter from harbor freight to measure my cabs ohms and to bias some of my amps and when trying to get ohms from my cabs the numbers are changing constantly. I have it set to 200, the lowest resistance setting and pulled the speaker cable with one end still in the cab. Both leads on cable tip, one on bottom and one on the tip. I am doing everything correct but the numbers keep changing and are all over the place no matter what I do. Can anyone recommend a stable, consistent meter that dont cost much. Thanks in advance!
 
Try a fresh battery. Also, unscrew the plug's outer case and try and get a good connection with the meter probes where the wires are soldered to the plug.
 
Mini does the same thing. Just did it yesterday. Lay the jack down on the top of the cabinet and firmly push the probes down. Give it a second and it’ll slow down and read it. It’ll fluctuate .5 or so.
 
I bought a cheap one from Walmart and it works great. I really don’t know how to use it other than checking for hot and ground wires for outlets and lights.
 
Mine does this when the battery is low. And, hold the tips down, try not to let them slide. It's annoying but keep steady...you'll get a good reading. For Bias, I have a simple bias tool that is a tube base, plugs into the amp then put the tube in, then two leads go to the multimeter. 10 buck off ebay 8 years back. Works great.
 
when you say one on bottom one on tip ......do you mean you have the ground probe ( black ) touching the sleeve of the jack and the red touching the tip ??
 
griff10672 said:
when you say one on bottom one on tip ......do you mean you have the ground probe ( black ) touching the sleeve of the jack and the red touching the tip ??
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Yes sir. But it does the same thing no matter how I try it.
 
demondestroyer said:
Just bought a cen tech 11 function digital multimeter from harbor freight to measure my cabs ohms and to bias some of my amps and when trying to get ohms from my cabs the numbers are changing constantly. I have it set to 200, the lowest resistance setting and pulled the speaker cable with one end still in the cab. Both leads on cable tip, one on bottom and one on the tip. I am doing everything correct but the numbers keep changing and are all over the place no matter what I do. Can anyone recommend a stable, consistent meter that dont cost much. Thanks in advance
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I would check the multi meter using a different funtion .... like check the voltage on a 9 volt battery or something you know what the result should be . see if it reads correctly ..... if not .... I would agree with the above about low battery
 
Racerxrated said:
Mine does this when the battery is low. And, hold the tips down, try not to let them slide. It's annoying but keep steady...you'll get a good reading. For Bias, I have a simple bias tool that is a tube base, plugs into the amp then put the tube in, then two leads go to the multimeter. 10 buck off ebay 8 years back. Works great.
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Would you by any chance remember the name of this bias tool? I have never heard of anything like that.
 
griff10672 said:
I would check the multi meter using a different funtion .... like check the voltage on a 9 volt battery or something you know what the result should be . see if it reads correctly ..... if not .... I would agree with the above about low battery
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Gonna try exactly this. Thanks!
 
demondestroyer said:
Would you by any chance remember the name of this bias tool? I have never heard of anything like that.
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demondestroyer said:
Would you by any chance remember the name of this bias tool? I have never heard of anything like that.
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this the one I use .....
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demondestroyer said:
Would you by any chance remember the name of this bias tool? I have never heard of anything like that.
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This is the same as what I have..although I bought mine from a guy in Minnesota but it was 8-9 yrs back. Just set your multimeter to milliamps and you can test each tube. The Eurotubes tester lets you test all 4 at once; but it's more expensive.

https://www.ebay.com/itm/364290994514?epid=1756103229&hash=item54d16f7152:g:1W0AAOSwq8tkf4pQ&amdata=enc:AQAIAAAA4JRltIifu3SAw1U0w1R//OLnnZsEQ+2xG1lL93n7oDITL0Vol2HN/JJHuoJTfcoVAsqMyfLHOohzk4KgezXdrRHes9gnoRfumrIxyv1dlkWb5NL2cqGm+S7lnuxv9OfH6xTVeeCvcjoSH/Or6EXFnQWSsAns8B4vko/8PH8LbpX0/To7bA9bRJj/MJFTkWYGR7BXGd82TE3dHeHTe4XIG+ufiosBKeuzABtxpSjsjYHRd1f6vQkgxrwhA5YgaEJ/lIg0l7xx3BreP5Irf9AwVqNdq3fsmigW8w9aQaHHgolg|tkp:Bk9SR9yC2p6qYg
 
 
griff10672 said:
I would check the multi meter using a different funtion .... like check the voltage on a 9 volt battery or something you know what the result should be . see if it reads correctly ..... if not .... I would agree with the above about low battery
Click to expand...
For sure. I have 2 cheap MMs, for double checking numbers and back up. For probes I think we all would highly recommend an octal bias probe (that then plugs into meter). Eurotubes and Weber both have a variety of probes in different price brackets.

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It changes because you're trying to measure AC IMPEDANCE on a DC RESISTANCE setting. Impedance is frequency dependent and will usually fluctuate up to 15% or so lower than the ohms rating
 
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