Hello everyone.
Perhaps a silly question. I am trying to repair a Sony HMK313 three-in-one music center.
It originally came with a ceramic cartridge, but I want to put in a MM magnetic cartridge.
Can I place a magnetic phono preamplifier internally and connect its output to the ceramic phono input of the equipment?.
Would the resulting frequency response be adequate?
Greetings and thanks.
Perhaps a silly question. I am trying to repair a Sony HMK313 three-in-one music center.
It originally came with a ceramic cartridge, but I want to put in a MM magnetic cartridge.
Can I place a magnetic phono preamplifier internally and connect its output to the ceramic phono input of the equipment?.
Would the resulting frequency response be adequate?
Greetings and thanks.
The simplest way is to buy or build an external phono stage, and connect it to the line inputs of the Sony.
Rayma, that's the idea. But I would like to not connect it to the auxiliary input, but to the ceramic phono input. That way it would be as original when selecting "phono".
As you say, connecting to auxiliary would not be original. To listen to Phono you have to select Aux.
What I wanted to know is if there is a difference in the frequency response between the aux and ceramic inputs.
As you say, connecting to auxiliary would not be original. To listen to Phono you have to select Aux.
What I wanted to know is if there is a difference in the frequency response between the aux and ceramic inputs.
Ceramic cartridges also require network, a one mega Ohm resistor at least if not anything more sophisticated. There would definitely something like that on the original phono input that is meant for a ceramic cartridge and you would need to bypass that if you are connecting a mm phono network there.
Regards,
It would very probably work fine. There are exceptions, but most inputs for ceramic cartridges are essentially line level inputs with a quite high input impedance. If you want to be sure, first connect some other line level source and check the result.
It didn't work. When connecting a tuner to the ceramic phono input the frequency response is increasing bass and decreasing treble.
The problem is that I couldn't get the service manual for the Sony HMK313.
So I can't identify where to correct or remove the frequency correction network.
The problem is that I couldn't get the service manual for the Sony HMK313.
So I can't identify where to correct or remove the frequency correction network.
Doing reverse engineering (I'm a doctor, not a technician or engineer. Just a hobbyist), I found that the ceramic phono input uses the same cassette preamp, changing the equalization elements.
In these, a 3k3 resistor and a 0.022uF capacitor are used.
At the same time, the signal passes through a 2M2 resistor placed between the ceramic capsule and the input.
What I did was eliminate the 3k3 resistor and the 0.022uF capacitor and attenuate the input signal with a resistive divider until the signal is similar in level to the others (radio and cassette).
Problem solved.
Now I can put an internal magnetic phono preamp in the input that was once ceramic.
Thanks anyway for your contributions.
In these, a 3k3 resistor and a 0.022uF capacitor are used.
At the same time, the signal passes through a 2M2 resistor placed between the ceramic capsule and the input.
What I did was eliminate the 3k3 resistor and the 0.022uF capacitor and attenuate the input signal with a resistive divider until the signal is similar in level to the others (radio and cassette).
Problem solved.
Now I can put an internal magnetic phono preamp in the input that was once ceramic.
Thanks anyway for your contributions.