Title: Making good AM out of an Icom Post by: KB1KFI on February 21, 2005, 09:27:29 PM Hi, this is my first post...
A simple, yet complex, question... Has anyone made any successfull mods to the Icom 706mk11g in the audio/modulation areas? Is it possible in your opinion to de-yellify this beast? Regards, Cliff K1KFI Title: Making good AM out of an Icom Post by: Art on February 22, 2005, 08:37:39 AM You can make the receiver better. . . in fact quite nice. Do the 6Kc filter thing and use an external AF amplifier. The TX requires major dehnyellification. I don't think any one has done it yet. Pressed to perform I would locate the DBM and use an external AF chain and impedance matching/isolation to feed it. . . . this site might help you with the reference materials;
http://www.geocities.com/k3xf/ic706.html Title: Making good AM out of an Icom Post by: Art on February 22, 2005, 03:06:44 PM I did some perusing of the schematic, board layout, and transmit theory for the IC-706mk2g. . . the balanced modulator is on the bottom of the main board (IC1041). I would feed an external audio input (pin 1) at line level through a 10dB fixed attenuator (say 600 Ohms in and 600 out for the purposes of experimentation) and a nice fat cap (a 4.7uF tantalum might be a good choice). I would set R1042 for about 5W carrier and adjust your input AF drive for about 20W PEP. AMfone - Dedicated to Amplitude Modulation on the Amateur Radio Bands
I don't know anyone who has done this yet so you are on the bleeding edge and of course, the standard disclaimer applies . . . you can really trash your radio if you are not familiar with small components and butcher the board. . .if you are not 100% sure you can handle it . . . don't -ap |