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#1 2014-03-08 16:31:22

snaper
Bloody beginner
Registered: 2014-01-14
Posts: 6

Feedback mod - enlight me please

Hy Guys,

I have almost all parts for my mod, and just checked my notes, and now I'm a bit...confused.
Is this wiring correct for the feedback mod?

https://dl.dropboxusercontent.com/s/kzk30xj1ix17abp/Notes%20%28page%2010%29.png?dl=1&token_hash=AAHqBEBiRf-R4aN5Nx41BC7ipDMZwGUxxEOpA_rUlKGqBg

https://www.dropbox.com/s/kzk30xj1ix17a … 010%29.png

Last edited by snaper (2014-03-08 16:34:56)

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#2 2014-03-09 13:20:44

MadModder
Bomb Jack
Registered: 2012-11-03
Posts: 32

Re: Feedback mod - enlight me please

Yes

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#3 2014-03-09 13:45:01

snaper
Bloody beginner
Registered: 2014-01-14
Posts: 6

Re: Feedback mod - enlight me please

MadModder wrote:

Yes

Thank you very much.

I was confused cause I've read somewhere ever that you have to ground the audio with the switch to "off" the feedback. As you can see I would like to add jacks to in and out and both of the jacks are grounded to the port.

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#4 2014-03-09 17:30:21

MadModder
Bomb Jack
Registered: 2012-11-03
Posts: 32

Re: Feedback mod - enlight me please

You don't have to, but if you don't have anything connected to your audio in port and have the feedback off you're gonna get perhaps more noise than it was originally.
One solution is to have a dummy plugg with a short inside (or maybe 100 Ohm). Put that in the audio in port and you have one grounded input. Noise gone. smile
Just remember to remove that plug before switching feedback on again...

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#5 2014-03-09 21:33:28

snaper
Bloody beginner
Registered: 2014-01-14
Posts: 6

Re: Feedback mod - enlight me please

I seeeee. Now everything is clear.
One question about the dummy.
I should just solder a 100 Ohm resistor between the Tip and the ground?

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#6 2014-03-09 21:59:43

MadModder
Bomb Jack
Registered: 2012-11-03
Posts: 32

Re: Feedback mod - enlight me please

Exactly. I haven't tried that myself, yet, but 100 Ohms should do the trick.
I'm not shure if the output transistor will blow if the feedback is turned all the way up (direct short in-out) and if there is a dummy plug with just a wire in... That way the output is shorted to ground too.
So I figure a resistor in the plug is safer if one forgets.

Another way to do it is if you have a jack with a pin that disconnects when you put a plug in. You then can wire the feedback so that it is disabled automatically when anything plugs into the input jack.

Last edited by MadModder (2014-03-09 22:03:21)

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#7 2014-04-21 16:17:25

snaper
Bloody beginner
Registered: 2014-01-14
Posts: 6

Re: Feedback mod - enlight me please

I did it, and its not working. The pot is working, if I plug a headphone to the audio in jack, there I can hear the incoming signal.
Is it possible that the motherboard connection cause the problem?
I've connected my wires to the audio/video connector...there are rumors that the mod works only with the audio in/out around the RF box.
Ive a c64c machine.

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