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HP 8903B Question ?

HP8903B

Member
2010-06-06 8:17 pm
I plan to buy a HP 8903B.
I will eventually hook it up to a computer and use Pete Millet's software.

Do you guys have any tips when purchasing the HP 8903 ?
What should I look out for ?
How can I make sure it works properly ?
Are there any options that is a must have ?
 
Hello,

The manual can be found on Agilent's website. Try this link 8903B Operation and Calibration Manual | Agilent

Calibration certificate?

From memory, i think there is a checking procedure. You need a coax cable 50 ohms, 1m long.

Must have: the GPIB-USB controller. Check the prices, I think Agilent is cheaper than National Instruments and Tektronix.

Guys, any other suggestions for manp111 ?

CHeers,

Serge
 
I plan to buy a HP 8903B.
I will eventually hook it up to a computer and use Pete Millet's software.

Do you guys have any tips when purchasing the HP 8903 ?
What should I look out for ?
How can I make sure it works properly ?
Are there any options that is a must have ?

I have the HP filter and a weighing filter.

The hp filter is good for avoiding mains noise when measuring.

Just because the unit pass selftest isn´t an insurance for it being accurate.

Some units are sold because they are out of calibrating range and need component exchange.

Buy from a known seller with good feedback or dirtcheap as a repair.
 

tomchr

Member
Paid Member
2009-02-11 12:58 am
Calgary
www.neurochrome.com
I plan to buy a HP 8903B.
I will eventually hook it up to a computer and use Pete Millet's software.

I think Millett's software requires the GPIB adaptors from National Instruments which are rather expensive. Personally, I use some MATLAB scripts and a GPIB-Ethernet controller made by Prologix.

What should I look out for ?
How can I make sure it works properly ?

If you have the option to view the equipment in person, look for the usual suspects - broke pieces, bent connectors, etc. Connect a power cable and power up the analyzer. It should default to 1 kHz, 0 V, RMS voltage measurement. Hook up a BNC cable from output to input (set the ground switches to GND). Punch in [AMPL] 1 [V/kHz]. You should see 1 V RMS on the right display and 1 kHz on the left. Hit [DISTN] and you should see 1 kHz on the right display and 0.01 % or below in the right display. Most units fall below 0.005 % in this test.

If you get this far, there's a good chance the equipment works. Run it through the complete performance check section of the service manual. I've tested a few of these analyzers and would still have to spend 2~3 hours going through the performance test to fully test the gear. You can have it professionally done as well.

Are there any options that is a must have ?

The front panel connectors are nice for home use, so OPT 001 would be less useful to me as this moves the connectors to the rear of the instrument. Not a huge deal, though. You can always get a couple of BNC-BNC bulkhead adaptors and bring the connectors out to a bracket of sorts.

The remaining options are all filters. I use the 400 Hz HP, 20 kHz LP, and 80 kHz LP all the time. I wouldn't live without those.

I actually use an HP8903A. It's a fine analyzer. The only difference between the A and the B is that the B has filter options and a true differential input.

~Tom
 
Before you go down that path it might be worth taking a look at this device. I was looking at the HP and GPIB but decided that it's a lot of $$$ to put it all together just for the fun of looking at the distortion levels, etc (I don't really care what it is as long as it sounds good to me). But always looking for a reason to get some more test equipment, I came across this and have one sitting on the bench. I have not had time to play with it other then loop back test, but it may be something that saves some money and does what you need at a good price.

I came across it looking at PC based scopes and somehow this popped in the search results. It is a new release so not sure if all the bells and whistles are in the software yet but looks promising.

QA400 Audio Analyzer

HTH

Sandy
 

cerocool

Member
2006-06-18 5:16 pm
I know this is an old thread, but an other opinions on if the 8903B is worth the extra money? I've always wanted to go with one and also gives me an excuse to buy a GPIB-USB controller (which I can use on other equipment.)

There are quite a few 8903B's on Ebay, even ones with traceable calibration for <$500
 

tomchr

Member
Paid Member
2009-02-11 12:58 am
Calgary
www.neurochrome.com
Depends... If you're like me and like pushing buttons on the front panel of an instrument, get the 8903A or 8903B. If you'd rather click with a mouse, get a good external sound card and build the Sound Card Interface by Pete Millett. I would go the latter route rather than buying a dedicated "audio measuring interface".

The dynamic range of the older HP gear is generally spec'ed to 80 dB. This limits the lowest THD you can measure to 0.01 %, which is fine for tube gear. Much of the gear actually beats the spec. My 8903A can measure down to 0.002 %. Modern sound cards can get you lower than that.

A calibrated 8903A or B in good condition for less than $500 is a steal.

~Tom