Hewlett Packard HP334A distortion analyzer - Marconi TF2005R Osc 

Hello, I recently got a working 334a and I'm learning how to use it. A correction to your description: The manual states the 334a has a high pass filter, not a notch filter. Later units, including i believe, the 339 actually use a notch filter.

I used to use the HP 334A to measure sinad at PYE Telecommunications back in the late 70s and early 80s A brilliant piece of kit

Could you use this as a cheesy SINAD meter? Sounds like they both work on the same principle?? I purchased a distortion meter and am waiting for to arrive. Thanks and 73's OM DE Jack, VEG

The great thing about that series of THD analyzers, is apparently, H-P made a huge number of them, so they're available for reasonable prices on Ebay. Because they're pre-SMD/LSI, they're easy to fix. Here's a rundown of the different models: 331A: The basic version. 332A: Has the RF AM detector for AM xmttr tests. 333A: Like the 331A, but with auto-null. 334A: Has both the AM detector & auto-null. Basic specs are the same for all four. Every serious audiophile should have one, and the 332A/334A are a real boon to those of us who work on AM BCB xmttrs.

Hi Ray, Thank you so much for the Distortion Analyser, and yes I had seen this video some time ago, and it still had its "blue" thumbs up I gave it before. Paul

Hi Ray, I have heard of distortion test equipment but never seen or had the pleasure of using them - I have never worked at a radio/TV service centre that had that type of equipment. Testing the distortion level on the audio output of a domestic radio sounds interesting my friend. Regards, Phil.

Just restored one, repaired and calibrated ru-vid.com/video/%D0%B2%D0%B8%D0%B4%D0%B5%D0%BE-NJxPiqW5Ww4.html ru-vid.com/video/%D0%B2%D0%B8%D0%B4%D0%B5%D0%BE-uzUv1s65ziQ.html

Two nice free pieces of "Kit" Ray! I never knew how they measured THD before. Well this is pretty simple and makes perfect sense to read the harmonics other than the prime freq that is notched out. 73s my friend, Tom

I am jealous of your clean bench!

A very good simplified way on how the distortion analyzer works without getting technical, "excellent"