Modifications for the ICOM - RogerK

Fig. 3. The location of the IF tap8. Make a hole big enough for the coax to exit the radio - I made a hole near the tuning knob. Alternatively there's probablyjust room inside around where the carry strap attaches to put a sub-miniature socket. I just left a short SMA lead pigtail flyout.9. Double check there's no shorts.10. Reassemble the radio.In a perfect world...a. Capacitively couple your General Coverage all mode HF radio to this IF output with, say, a 1nF cap.b. Use an impedance matching attenuator on the IF output.I didn't bother with (b), and I'm not sure it made a lot of difference as the IF is so strong at this tapping point.Make sure that having done the mod you don't transmit into the IC-R3, and make sure that if there's any DC short or DC preampvoltage etc on your IF General Coverage All Mode HF Receiver that you capacitively couple (see (a) above) the IF out. ISTRONGLY suggest that you either use a receiver (as opposed to a transceiver), or if you do use an HF transciever, use an RXonly (or 'beverage') antenna socket - transmitting directly into an R3 will cost you dearly.The problem #2 of the deafness of the IC-R3 in the GHz can only be rectified with a low noise preamp with at least 20dB gain toovercome this receiver's poor sensitivity. Yes it really really is very very deaf. I listened to AO-40 with a signal strong enough todecode with a 25dB preamp switched in at the radio, and it was not possible to even tell there was a signal there without thepreamp.The IF tap's centre frequency is 26.050MHz, and is fairly wide so you tune your IC-R3 to within a few tens of kHz, and fine tuneyour HF RX around 26.050MHz (see fig.4.).