On Wednesday, April 7, 1999 at 12:00:00 AM UTC-7, John and Lucy Hayward-Warburton wrote:
Thanks for reading this.
Does anyone have information on the Garrard Music Recovery Module,
type number MRM101? It's an analogue vinyl click-and-pop remover
that looks for the signature of an LP scratch, and then briefly
mutes the delayed output from the cartridge so that you hear approx.
1ms silence instead of a click. They were made in the late 1970s.
I have such a beast, whose bucket-brigade delay, RIAA preamp and
opto-electronics (to do the muting) are in perfect working order
(and the amp, on its own, without the slightly noisy delay, sounds
nice), However, the circuit (probably some kind of differentiator)
that does the detection doesn't appear to work, although it *is*
receiving an input.
My manual contains a circuit diagram that OMITS the detector and
opto-electronics! Even the ICs on the circuit-board have their
numbers scraped off to prevent (my) reverse-engineering.
Any ideas? It worked until 1984, and cost me £20 in 1979.
Yours,
John Hayward-Warburton
I Have one and it is for sale