Purchase via EBAY a Distortion measurement set HP 339A from an supplier from Israel. This morning it arrived an I did some quick tests. It is a good functional set and I am now very happy with it to test the THD of my tube amp designes. Oh yes, the Forum will shout to me " but there are very good software tools to do that job" and, yes, I agree. But anyway I am glad to have a set that will do that job also.
Here a picture of my set:
Here a picture of my set:
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I was looking at those exact ones and yes, the forum convinced me away from a purchase. Congrats, I still think they are cool devices.
Looks good from the photo. A word of warning with cleaning the front panel with the clear dials - the numbers are printed on the underside of the plastic and if you leave the cleaning liquid there for some time (it won't dry), the black stencils will disappear!