Help with HP 400EL

[Coytee]

So, I have one of these items.  Looks like it's an AC Voltmeter.

 

I'm not an EE, I'm not even a small 'e' nor, did I stay in a Holiday Inn last night... 

 

Can someone tell me in fairly lay terms, what I can do with this thing?

 

Here's what has me curious...  my two rear LaScalas are hooked up to a dbx-BX3 amp.  The amp has gain controls.  Unless I have the balance screwed up inside my (new to me AND unfamiliar to me) AVR, the amp has to be skewed to one side to get the sound balanced.

 

Let me word it differently....

 

One LaScala will crank things out, the other one has to have the gain almost maxed to do similar.

 

I'm thinking that is where this can come in???

 

I think I can turn things up, measure the volts at the speaker to make sure the amp is putting out the same volts on each channel?

 

If accurate, do I just put the probes on the speaker inputs in parallel?  Do I instead, REMOVE the wires from the speaker and put them directly on the probe?

 

Will both the above get me blown up?

 

I've never used this and bought it on a whim (I think on the suggestion of Al K)  I've probably had it 10 years and never plugged it in a single time.

 

I'm wondering if now is the time.

 

Thoughts?

[JL Sargent]

I present you the manual!

 

http://www.davmar.org/pdf/HP400EL.pdf

[Arkytype]

Coytee,

 

You have a nice Hewlett Packard 400EL which is a wide band (10Hz-10MHz) and wide range (1mV to 300V) AC voltmeter. The "L" in the 400EL model means that the meter has a linear dB scale on top and a logarithmic voltage scale underneath. Most analog AC voltmeters have a linear voltage scale above the logarithmic dB scale making it harder to see small dB changes. You don’t need a calibrated eyeball to see changes as small as 0.05 dB on your 400EL meter scale!

The first step in troubleshooting your problem is to turn both volume controls of your BX-3 to the same “time” setting; e.g. ten o’clock. Now play music and note which La Scala is louder, left or right. For sake of illustration, let’s say the right La Scala is louder than the left. Stop the music and at the rear of the BX-3 swap the left and right channel speaker wires. Again, play music and note which La Scala is louder. If the right La Scala is still  louder than the left, there’s something wrong with the left La Scala. If the left  La Scala is now louder than the right, then your problem is with the BX-3 or the AVR.

 

Since the BX-3 is a four channel amplifier, you could repeat the above troubleshooting steps using the left and right front amplifier channels. That way you can double check if you have a La Scala or a BX-3/AVR problem.

 

If you determine one of your La Scalas is the problem, PM me and I’ll send you a comprehensive troubleshooting guide which includes using your HP 400EL to determine if you have a crossover network or driver problem.

 

Lee