[BC] Equipment Hall Of Fame

[Milton R Holladay Jr.]

Simpson -or anyone else- never made a VU meter that had ballistics that
looked "correct" like a Weston
M
----- Original Message ----- 
From: "PeterH5322" <peterh5322 at rattlebrain.com>
To: "Broadcasters' Mailing List" <broadcast at radiolists.net>
Sent: Tuesday, April 10, 2007 1:12 PM
Subject: Re: [BC] Equipment Hall Of Fame


>
> >As a lab exercise, one instructor had the class measure and plot the
> >frequency response of an 260 and a digital meter (fluke, but I don't
> >remember the model).  The 260 was flat out past 20kHz, the digital meter
> >response didn't go past 1 kHz.  I would never use a digital meter on
> >anything but 60 Hz circuits unless I had measured the frequency response.
>
> Although I previously nominated the Weston Model 30 VU meter, I'll now
> add my nomination for the Simpson 142 VU meter.
>
> The 142 is as close to a Weston as one can get in an affordable package,
> and it DOES use a copper oxide rectifier, which the VU meter standard
> mandates.
>
> What sets the 142 apart is its frequency response.
>
> It is used to set the erase current and the record bias current in Ampex
> 351s, and these have a several hundred kHz bias, so the meter's response
> goes out that far.
>
> Alas, the copper oxide rectifier adds some distortion to the output, so
> most knowledgeable operators disable the meter when in reproduce mode.
>
> I agree that DVMs generally have poor frequency response. But, the best
> of them ARE "true RMS", and this characteristic is essential in certain
> applications.