From jocke@netcontrol.fi Tue Mar 12 17:50:48 1996 12 Mar 96 20:50:42 +0500 11 Mar 96 05:07:59 +0500 3: 23 -0800 Date: Mon, 11 Mar 1996 09:39:55 +0200 (EET) From: Joachim Verghese Cc: analogue@hyperreal.com Subject: Re: Arp filter mod. On Sun, 10 Mar 1996, I. Onsager wrote: > Weyer-Smith labs offers a modification for the Arp 4072 filter to expand > frequency response. Is this Weyer-Smith proprietary information, or is > it public available on the net? > Anybody out there that has tried it? I've done it to some 4075s (very similar to the 4072). The four 4K7 current limiting resistors which are connected between the exponential converter and the four discrete gain stages should be lowered to 2K2. If memory serves, these are the only 4K7 resistors in the module, so locating them shouldn't be too difficult. Alternatively, you could add another set of 4K7s in parallel with the existing ones. These could be mounted on the solder side of the board. Beware of possible shorting to other pins, though. -joachim