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47-1230 replacement phono - matching transformer required?
#16

Hi Mars,

If you are unable to dig up the stereo that you tested with, the cheapest alternative and one that you will find to be easier and more in tune with your desire to not modify the system would be to install the P51 ceramic cartridge from the V-M website, as it is only about $25 with screws and connectors. This is a monaural cartridge. The needle used in that cartridge is extremely common.

If it overdrives the phono amp (and I think that it will, you can easily attenuate it by making a voltage divider using a 200K resistor and 2 meg resistor in series with the 200K at ground and the 2 meg at the phono grid and the cartridge leads across the 200K resistor. Alternately, obtain a 1 meg audio taper potentiometer and wire it thusly:
from the rear view of the pot, the right terminal goes to chassis ground. The left terminal goes to the grid of the phono amp stage. the cartridge goes between the right terminal and the middle terminal.

Hope that helps.

"Do Justly, love Mercy and walk humbly with your God"- Micah 6:8
"Let us begin to do good"- St. Francis

Best Regards, 

MrFixr55
#17

Thanks MrFixr55
I will try that. 

Do I keep the phono connected the way it currently is?

Hunting a cartridge isn't something I have done before... Thanks a lot for the help.

-Mars
#18

Hi Mar,

I suspect that the new cartridge will overdrive the phono amp. We'll cross that bridge when we get to it. Options include either adding a control to adjust the gain of that stage or to bypass that stage.

"Do Justly, love Mercy and walk humbly with your God"- Micah 6:8
"Let us begin to do good"- St. Francis

Best Regards, 

MrFixr55
#19

Having issue finding the cartridge, I sent them a query. The guy at v-m is suggesting a p228 that is apparently an awesome fit in that tone arm and should in theory fit the ~1V the 47-1230 likes.

It's a stereo cartridge but he says it's possible to connect to the mono tonearm with minimal hassle.

   

I guess it somewhat matches what we were looking for - except the mono part, but with confidence it'll install easily.

-Mars




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