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Madison 8719

Posted: Tue Sep 20, 2016 8:37 pm
by redlght
Does the washington rx tx mod apply to this since it has a dual conversion 455khz murata which the washignton does not and the cobra 2000 does not have the same L's as the madison either

Re: Madison 8719

Posted: Tue Oct 11, 2016 12:33 pm
by redlght
I think this post got buried at the bottom :D

Re: Madison 8719

Posted: Tue Oct 11, 2016 10:16 pm
by 31
Red light , I've modded both 2000/148 and Madison's . Both flip clock and digital ones. They are all the same , if you're looking at changing the 455khz IF filter, it's all the same one. These radios sound super good once modded. The alignment will make or break the receiver. I can't remember of hand if the Madison used C77 for the tone cap or not but in all my radios , if the tone cap is there or not , I'll add a 1 uf to ground. It may muddy the sound slightly but takes the hiss out and add a speaker with a good surround on the cone and wait for the rumble. Of course you'll have to wait for someone wide to come in but now days , there's much more wide stations out there then before. If you feel like getting jiggly with it, follow the 148 schematic on CBtricks that talk about changing values in the noise blanker for a better NB. Schottkeys do very well in the detectors also.

Re: Madison 8719

Posted: Tue Oct 11, 2016 10:23 pm
by 31
Not the best but something I pieced together from the forum over at cbtricks . There is also some differences and I found the 2000/148 schematic to be a little closer to the the Madison's I was working on.
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