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Re: Help with problems



Jerry,
A couple of thoughts on the description of your system:
- the hardware combination is working nominally since you can hear the beacon at times and is, on the face of it, plenty good to give you a terrific s/n ratio when conditions are "right."
- the very weak signals could be due to several things that are hard to detect, including a bad cable or connector between the d/c and the rig and possibly even a bad power insertion device.  Check your cable(s) from one end to the other, including connectors with an Ohmeter.  You might also try a different tee, maybe making one up for test with just a small value poly capacitor to test the signal level (connect it with alligator clips between two cables and apply power to the cable on the d/c side).
- I used to own an IC-820H and the radio will "hear a flea spit" when working properly.  Both the IC-820H and 821H have grear receivers.  When I got mine it was fine on FM but deaf on SSB.  There was a faulty diode in the ring mixer--a cheap and easy fix.
- Finally, here's the big item you did not mention:  when are you listening?  It is important to note the squint when giving signal reports.  On Saturday and Sunday the squint over Texas was horrible.  Yes, there were some QSO's.  I even had a few with the squint well over 25 degrees, but the signals were definitely close to or "in the noise."  I have good DSP capabilities in my current rig and that helps, but is certainly not anything like the difference between strong signals when squint is low and rough copy like last weekend.  My rough observation is AO-40 has two good days, in terms of visibility and squint, a week here in Texas.  And... most of the good time is either when I am at work or sleeping :-)
73,
Jerry, K5OE

In a message dated Wed, 5 Sep 2001  3:28:16 AM Eastern Daylight Time, "Gerald Payton" <n5gpc@earthlink.net> writes:

> Last time I was admonished for saying it was a "stupid question."  Perhaps,
> I should rephrase it and say, "a question from a stupid person."  I REALLY
> feel inapt for having to ask these questions.
> 
> Yes, I know that everyone on the BB has had to start sometime, but these
> problems seem like they "should" be relatively easy to overcome.
> 
> (Setup= IC-820 H, Andrew 26T-2400 Grill antenna, DEM 13ULNA Pre Amp,
> Millicon MC-251 d/c and LMR-400 coax.)
> 
> Problem One:   The signal to noise ratio seems that it should be better.
> >From my previous post, I'm told that my setup is nominal.
> I receive the MB very well, but the QSO's are very weak and down near the
> noise level.
> 
> Adjusting my SHIFT helps some, but the majority are still not good enough
> for contact.  I believe that if I cannot hear the audio, I should not try a
> contact!  Therefore, I'm still unable to attempt a contact.
> 
> I am just wondering if a newer radio with DSP and better filtering and shift
> adjustment might be the cure.  Of course, I'm sooooo
> frustrated now, I'm about ready to throw in the towel and sell everything!
> 
> Problem Two:   I have been able to adjust my uplink signal (70cm) and hear
> it returned.  However, it too was very weak on return.  And, then with
> additional tests, I no longer hear my downlink signal.  I don't know if I
> have an "tracking" problem with the IC-820 or not.  It appears to be
> operating OK when looking at the radio (LSB up, USB down and reversed
> transponder).
> 
> Analyzing all this in my mind, I can't help but believe that some sort of
> selectivity (DSP, Shift or something) would help reduce the noise to a level
> which I could hear well.  I realize that preamps and such amplify BOTH audio
> and noise and separating the two is difficult.
> 
> I hate to be so close and have spend money that I can't really afford and
> then give up.  I'm not an experienced SSB operator and am not familiar with
> operating SSB and adjusting for same.
> 
> Sorry for the "crying towel", but I am really frustrated............
> 
> 73 to ALL,
> Jerry  N5GPC
> 
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