[AMRadio] Best AM BoatanchorReceiver or AM RiceboxReceiver

Jim Wilhite w5jo at brightok.net
Sun Oct 1 12:33:28 EDT 2006

Jim I listened to the same groups as you yesterday on an SX 117.  I did not 
have any trouble copying each of the groups.  While some of the aflack noise 
could be heard, it did not affect my copy that much.  I turned on the HRO 60 
with the D coil in the General Coverage mode and was able to copy very well 
with it.

I am about 500 miles North of you and was using a dipole and an inverted L 
on both receivers.  I didn't try the NC 183D but it tends to be almost as 
selective as the HRO.  I also have an R 75 and I really don't see that much 
of an improvement in reception.  I do not have all the filters in it as you 
do, but the S- AM mode does not help that much.  Also my R 75 does not have 
any modifications.

73  Jim

> Hi All,
>   Yesterday morning on 75 meters we had at least 3 AM QSO's going on
> simultaniously. It was glorious! I heard QSO's on 3880, 85, and 90. At the
> same time there were SSB groups on 3878, and 3894.
> At my QTH (central Texas) with my equipment, my SP-600 was useless. Yes I
> could use the 3Kc IF bandpass position, and tune off center to favor one
> sideband or another. As soon as the audio midrange would brighten up I'd
> hear QRM from an adjacent channel. Switching in the 8kc position resulted 
> in
> a maddening array of signals besides the one I was wanting to hear.
> Then I switched to my Icom R-75 with 3 mechanical filters that are about
> 2.4, 3.5 and 6 khz in bandwidth. I could hear all 3 QSO's Q5 in AM with 
> the
> 3.5 Khz filter, but it was no fun because the upper mids, and all highs 
> were
> gone. Then tune off 1 Khz, and much better or turn on the synchronous
> detector, offset the passband tuning 2.4 khz (or 3.5), select the 2.4 
> filter
> (or 3.5), and golly Gee! Nice sounding AM on all 3 QSO's so long as you 
> pick
> the better sideband.
> As the morning went on the QRM went away, and all we had was the traders 
> net
> on 3890. Now the SP-600 ruled until the signals started dropping from
> daytime propagation kicking in. Now I was experiencing QSB, selective
> sideband fading, and occasional impulse line noise. Switch back to the 
> R-75,
> turn on the noise blanker, and synchronous detector. Back to Q5 again!!
> This is not a tube versus solid state issue. Chuck Wa0zhh has a all tube 
> HB
> receiver that has most of the modern features, and his receiver can 
> probably
> blow the doors off my R-75. Chuck likes old style octal tubes too like the
> 6L7 in his noise blanker circuit.
> So how would a R-390 have done yesterday, or a NC-183D, Bretts HB tube
> receiver, or one of Darrel's HB tube receivers?? Just curious.
> Jim

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